diff --git a/packages/shared/src/components/FeedItemComponent.tsx b/packages/shared/src/components/FeedItemComponent.tsx
index 99382f176a6..39970ce1ee7 100644
--- a/packages/shared/src/components/FeedItemComponent.tsx
+++ b/packages/shared/src/components/FeedItemComponent.tsx
@@ -20,6 +20,7 @@ import { FeedItemType } from './cards/common/common';
 import { AdGrid } from './cards/ad/AdGrid';
 import { AdList } from './cards/ad/AdList';
 import { SignalAdList } from './cards/ad/SignalAdList';
+import type { AdCardProps } from './cards/ad/common/common';
 import { AcquisitionFormGrid } from './cards/AcquisitionForm/AcquisitionFormGrid';
 import { AcquisitionFormList } from './cards/AcquisitionForm/AcquisitionFormList';
 import { FreeformGrid } from './cards/Freeform/FreeformGrid';
@@ -394,9 +395,12 @@ function FeedItemComponent({
   }
 
   switch (item.type) {
-    case FeedItemType.Ad:
+    case FeedItemType.Ad: {
+      const AdComponent = AdTag as React.ForwardRefExoticComponent<
+        AdCardProps & React.RefAttributes<Element>
+      >;
       return (
-        <AdTag
+        <AdComponent
           ref={inViewRef}
           ad={item.ad}
           index={item.index}
@@ -409,6 +413,7 @@ function FeedItemComponent({
           }
         />
       );
+    }
     case FeedItemType.UserAcquisition:
       return <AcquisitionFormTag key="user-acquisition-card" />;
     case FeedItemType.MarketingCta:
diff --git a/packages/shared/src/components/LoginButton.spec.tsx b/packages/shared/src/components/LoginButton.spec.tsx
index 9747eb252eb..eec80ce67e7 100644
--- a/packages/shared/src/components/LoginButton.spec.tsx
+++ b/packages/shared/src/components/LoginButton.spec.tsx
@@ -18,7 +18,9 @@ describe('LoginButton', () => {
     logEvent.mockReset();
   });
 
-  const renderLayout = (user: LoggedUser = null): RenderResult => {
+  const renderLayout = (
+    user: LoggedUser = null as unknown as LoggedUser,
+  ): RenderResult => {
     const client = new QueryClient();
 
     return render(
diff --git a/packages/shared/src/components/ProfileMenu/ProfileSectionItem.tsx b/packages/shared/src/components/ProfileMenu/ProfileSectionItem.tsx
index 9337e940aee..77688c441aa 100644
--- a/packages/shared/src/components/ProfileMenu/ProfileSectionItem.tsx
+++ b/packages/shared/src/components/ProfileMenu/ProfileSectionItem.tsx
@@ -9,7 +9,6 @@ import {
   TypographyTag,
   TypographyType,
 } from '../typography/Typography';
-import ConditionalWrapper from '../ConditionalWrapper';
 import { combinedClicks } from '../../lib/click';
 import { ArrowIcon, OpenLinkIcon } from '../icons';
 import { anchorDefaultRel } from '../../lib/strings';
@@ -55,56 +54,54 @@ export const ProfileSectionItem = ({
   typography,
 }: ProfileSectionItemProps): ReactElement => {
   const isMobile = useViewSize(ViewSize.MobileL);
-
   const tag = href ? TypographyTag.Link : TypographyTag.Button;
-
   const showLinkIcon = href && external;
   const openNewTab = showLinkIcon && !href.startsWith(webappUrl);
-
-  return (
-    <ConditionalWrapper
-      condition={!!href}
-      wrapper={(children) => (
-        <Link href={href} passHref>
-          {children}
-        </Link>
+  const content = (
+    <Typography<typeof tag>
+      tag={tag}
+      color={typography?.color ?? TypographyColor.Tertiary}
+      type={typography?.type ?? TypographyType.Subhead}
+      className={classNames(
+        'flex h-10 cursor-pointer items-center gap-2 rounded-10 px-1 tablet:h-8',
+        (href || onClick) && 'hover:bg-surface-float',
+        isActive ? 'bg-surface-active' : undefined,
+        className,
       )}
+      {...combinedClicks(() => onClick?.())}
+      {...(openNewTab && { target: '_blank', rel: anchorDefaultRel })}
     >
-      <Typography<typeof tag>
-        tag={tag}
-        color={typography?.color ?? TypographyColor.Tertiary}
-        type={typography?.type ?? TypographyType.Subhead}
-        className={classNames(
-          'flex h-10 cursor-pointer items-center gap-2 rounded-10 px-1 tablet:h-8',
-          (href || onClick) && 'hover:bg-surface-float',
-          isActive ? 'bg-surface-active' : undefined,
-          className,
-        )}
-        {...combinedClicks(() => onClick?.())}
-        {...(openNewTab && { target: '_blank', rel: anchorDefaultRel })}
-      >
-        {Icon && (
-          <Icon
-            secondary={isActive}
-            size={isMobile ? IconSize.Small : IconSize.XSmall}
-          />
-        )}
-        <span>{title}</span>
+      {Icon && (
+        <Icon
+          secondary={isActive}
+          size={isMobile ? IconSize.Small : IconSize.XSmall}
+        />
+      )}
+      <span>{title}</span>
 
-        {!isMobile && showLinkIcon && (
-          <OpenLinkIcon
-            className="ml-auto text-text-quaternary"
-            size={IconSize.Size16}
-          />
-        )}
+      {!isMobile && showLinkIcon && (
+        <OpenLinkIcon
+          className="ml-auto text-text-quaternary"
+          size={IconSize.Size16}
+        />
+      )}
 
-        {isMobile && !external && (
-          <ArrowIcon
-            className="ml-auto rotate-90 text-text-quaternary"
-            size={IconSize.Size16}
-          />
-        )}
-      </Typography>
-    </ConditionalWrapper>
+      {isMobile && !external && (
+        <ArrowIcon
+          className="ml-auto rotate-90 text-text-quaternary"
+          size={IconSize.Size16}
+        />
+      )}
+    </Typography>
+  );
+
+  if (!href) {
+    return content;
+  }
+
+  return (
+    <Link href={href} passHref>
+      {content}
+    </Link>
   );
 };
diff --git a/packages/shared/src/components/auth/AuthenticationBanner.tsx b/packages/shared/src/components/auth/AuthenticationBanner.tsx
index 75c33a51408..e0daedef18d 100644
--- a/packages/shared/src/components/auth/AuthenticationBanner.tsx
+++ b/packages/shared/src/components/auth/AuthenticationBanner.tsx
@@ -50,7 +50,7 @@ export function AuthenticationBanner({
         <Section className="w-[23.25rem]">
           <AuthOptions
             ignoreMessages
-            formRef={null}
+            formRef={null as unknown as React.MutableRefObject<HTMLFormElement>}
             trigger={AuthTriggers.Onboarding}
             simplified
             defaultDisplay={AuthDisplay.OnboardingSignup}
diff --git a/packages/shared/src/components/auth/CodeVerificationForm.tsx b/packages/shared/src/components/auth/CodeVerificationForm.tsx
index 7206755ebca..d4ed0858c75 100644
--- a/packages/shared/src/components/auth/CodeVerificationForm.tsx
+++ b/packages/shared/src/components/auth/CodeVerificationForm.tsx
@@ -41,7 +41,7 @@ function CodeVerificationForm({
         setEmailSent(true);
       },
       onVerifyCodeSuccess: () => {
-        onSubmit();
+        onSubmit?.();
       },
     },
   );
diff --git a/packages/shared/src/components/auth/CustomAuthBanner.tsx b/packages/shared/src/components/auth/CustomAuthBanner.tsx
index 95b61a3a230..addb44421b8 100644
--- a/packages/shared/src/components/auth/CustomAuthBanner.tsx
+++ b/packages/shared/src/components/auth/CustomAuthBanner.tsx
@@ -7,7 +7,7 @@ import { useViewSize, ViewSize } from '../../hooks';
 import LoginButton from '../LoginButton';
 import { authGradientBg } from '../banners';
 
-const CustomAuthBanner = (): ReactElement => {
+const CustomAuthBanner = (): ReactElement | null => {
   const { shouldShowAuthBanner } = useOnboardingActions();
   const { shouldShowLogin } = useAuthContext();
   const isLaptop = useViewSize(ViewSize.Laptop);
diff --git a/packages/shared/src/components/auth/EmailSignupForm.tsx b/packages/shared/src/components/auth/EmailSignupForm.tsx
index 74ce83ef8f9..9ce1c0c65b6 100644
--- a/packages/shared/src/components/auth/EmailSignupForm.tsx
+++ b/packages/shared/src/components/auth/EmailSignupForm.tsx
@@ -18,7 +18,7 @@ function EmailSignupForm({
   isReady,
   showDisclaimer = true,
 }: EmailSignupFormProps): ReactElement {
-  const [email, setEmail] = useState(null);
+  const [email, setEmail] = useState<string | null>(null);
   const inputId = useId();
   const isSubmitDisabled = !email || !isReady;
 
diff --git a/packages/shared/src/components/auth/SignBackButton.tsx b/packages/shared/src/components/auth/SignBackButton.tsx
index 321aa8e6710..7524b36af4c 100644
--- a/packages/shared/src/components/auth/SignBackButton.tsx
+++ b/packages/shared/src/components/auth/SignBackButton.tsx
@@ -18,7 +18,7 @@ export function SignBackButton({
   disabled = false,
   onClick,
 }: SignBackButtonProps): ReactElement {
-  const item = providerMap[provider];
+  const item = providerMap[provider.toLowerCase() as keyof typeof providerMap];
 
   return (
     <button
diff --git a/packages/shared/src/components/auth/common.tsx b/packages/shared/src/components/auth/common.tsx
index 50bdc91a1d1..cfb59e49373 100644
--- a/packages/shared/src/components/auth/common.tsx
+++ b/packages/shared/src/components/auth/common.tsx
@@ -64,10 +64,10 @@ export interface AuthFormProps {
 export const getFormEmail = (e: React.FormEvent): string => {
   const form = e.currentTarget as HTMLFormElement;
   const input = Array.from(form.elements).find((el) =>
-    ['email', 'traits.email'].includes(el.getAttribute('name')),
+    ['email', 'traits.email'].includes(el.getAttribute('name') ?? ''),
   ) as HTMLInputElement;
 
-  return input?.value?.trim();
+  return input?.value?.trim() ?? '';
 };
 
 export enum AuthDisplay {
diff --git a/packages/shared/src/components/buttons/Button.spec.tsx b/packages/shared/src/components/buttons/Button.spec.tsx
index 171fbe74432..ed8829a9804 100644
--- a/packages/shared/src/components/buttons/Button.spec.tsx
+++ b/packages/shared/src/components/buttons/Button.spec.tsx
@@ -13,7 +13,7 @@ import { UpvoteIcon } from '../icons';
 const renderComponent = <Tag extends AllowedTags>(
   props: Partial<ButtonProps<Tag>> = {},
 ): RenderResult => {
-  return render(<Button {...props} />);
+  return render(<Button {...(props as ButtonProps<'button'>)} />);
 };
 
 describe('Button', () => {
diff --git a/packages/shared/src/components/buttons/QuaternaryButton.tsx b/packages/shared/src/components/buttons/QuaternaryButton.tsx
index 0beb9444ce3..26c171e2179 100644
--- a/packages/shared/src/components/buttons/QuaternaryButton.tsx
+++ b/packages/shared/src/components/buttons/QuaternaryButton.tsx
@@ -31,7 +31,13 @@ function QuaternaryButtonComponent<TagName extends AllowedTags>(
   ref?: Ref<ButtonElementType<TagName>>,
 ): ReactElement {
   const anchorRef = useRef<ButtonElementType<TagName>>(null);
-  useImperativeHandle(ref, () => anchorRef?.current);
+  useImperativeHandle(ref, () => {
+    if (!anchorRef.current) {
+      throw new Error('QuaternaryButton ref is not attached');
+    }
+
+    return anchorRef.current;
+  });
   const [isHovered, setIsHovered] = useState(false);
   const onLabelClick = (event: React.MouseEvent<HTMLLabelElement>): void => {
     event.preventDefault();
diff --git a/packages/shared/src/components/cards/Leaderboard/LeaderboardListItem.tsx b/packages/shared/src/components/cards/Leaderboard/LeaderboardListItem.tsx
index 5bfeb3eeb69..2ecb351f1f2 100644
--- a/packages/shared/src/components/cards/Leaderboard/LeaderboardListItem.tsx
+++ b/packages/shared/src/components/cards/Leaderboard/LeaderboardListItem.tsx
@@ -1,7 +1,6 @@
 import type { ReactElement, ReactNode } from 'react';
 import React from 'react';
 import { largeNumberFormat } from '../../../lib';
-import ConditionalWrapper from '../../ConditionalWrapper';
 import Link from '../../utilities/Link';
 import { Tooltip } from '../../tooltip/Tooltip';
 
@@ -26,26 +25,28 @@ export function LeaderboardListItem({
   const shouldShowTooltip =
     concatScore && typeof index === 'number' && index >= 1000;
   const actualNumber = index.toLocaleString();
+  const content = (
+    <>
+      <Tooltip content={actualNumber} visible={shouldShowTooltip}>
+        <span className="inline-flex w-14 shrink-0 justify-center tabular-nums text-text-quaternary">
+          {formattedNumber}
+        </span>
+      </Tooltip>
+      {children}
+    </>
+  );
 
   return (
     <li className={className} onMouseEnter={onMouseEnter}>
-      <ConditionalWrapper
-        condition={!!href}
-        wrapper={(child) => (
-          <Link href={href} passHref key={href} prefetch={false}>
-            <a className="flex w-full flex-row items-center rounded-8 px-2 hover:bg-accent-pepper-subtler">
-              {child}
-            </a>
-          </Link>
-        )}
-      >
-        <Tooltip content={actualNumber} visible={shouldShowTooltip}>
-          <span className="inline-flex w-14 shrink-0 justify-center tabular-nums text-text-quaternary">
-            {formattedNumber}
-          </span>
-        </Tooltip>
-        {children}
-      </ConditionalWrapper>
+      {href ? (
+        <Link href={href} prefetch={false}>
+          <a className="flex w-full flex-row items-center rounded-8 px-2 hover:bg-accent-pepper-subtler">
+            {content}
+          </a>
+        </Link>
+      ) : (
+        content
+      )}
     </li>
   );
 }
diff --git a/packages/shared/src/components/cards/ad/common/getAdFaviconImageLink.spec.ts b/packages/shared/src/components/cards/ad/common/getAdFaviconImageLink.spec.ts
index 1b7959f2811..3c05e20bcea 100644
--- a/packages/shared/src/components/cards/ad/common/getAdFaviconImageLink.spec.ts
+++ b/packages/shared/src/components/cards/ad/common/getAdFaviconImageLink.spec.ts
@@ -3,9 +3,19 @@ import { apiUrl } from '../../../../lib/config';
 import { adFaviconPlaceholder } from '../../../../lib/image';
 import { getAdFaviconImageLink } from './getAdFaviconImageLink';
 
+const originalWindowDescriptor = Object.getOwnPropertyDescriptor(
+  globalThis,
+  'window',
+);
+
 describe('getAdFaviconImageLink', () => {
   afterEach(() => {
-    delete (globalThis as typeof globalThis & { window?: Window }).window;
+    if (originalWindowDescriptor) {
+      Object.defineProperty(globalThis, 'window', originalWindowDescriptor);
+      return;
+    }
+
+    Reflect.deleteProperty(globalThis, 'window');
   });
 
   it('returns companyLogo first when available', () => {
@@ -29,6 +39,11 @@ describe('getAdFaviconImageLink', () => {
   });
 
   it('uses a large fallback favicon size during SSR when window is unavailable', () => {
+    Object.defineProperty(globalThis, 'window', {
+      configurable: true,
+      value: undefined,
+    });
+
     expect(
       getAdFaviconImageLink({
         ad: { ...ad, adDomain: 'daily.dev' },
diff --git a/packages/shared/src/components/cards/article/ArticleGrid.spec.tsx b/packages/shared/src/components/cards/article/ArticleGrid.spec.tsx
index 63a3aa4a41d..e56c15ccc6a 100644
--- a/packages/shared/src/components/cards/article/ArticleGrid.spec.tsx
+++ b/packages/shared/src/components/cards/article/ArticleGrid.spec.tsx
@@ -102,7 +102,7 @@ it('should call on share click on copy link button click', async () => {
 it('should not display publication date createdAt is empty', async () => {
   renderComponent({
     ...defaultProps,
-    post: { ...post, createdAt: null },
+    post: { ...post, createdAt: undefined },
   });
   const el = screen.queryByText('Jun 13, 2018');
   expect(el).not.toBeInTheDocument();
diff --git a/packages/shared/src/components/cards/brief/BriefBanner/BriefBannerFeed.tsx b/packages/shared/src/components/cards/brief/BriefBanner/BriefBannerFeed.tsx
index b7dea4581c6..9c3b2a82f2c 100644
--- a/packages/shared/src/components/cards/brief/BriefBanner/BriefBannerFeed.tsx
+++ b/packages/shared/src/components/cards/brief/BriefBanner/BriefBannerFeed.tsx
@@ -42,7 +42,7 @@ const BriefBannerWithContext = ({ style, ...props }: ComponentProps<'div'>) => {
 
   const saveBannerState = useCallback(() => {
     if (bannerLastSeenRef.current !== null) {
-      updateAlerts({ briefBannerLastSeen: bannerLastSeenRef.current });
+      updateAlerts?.({ briefBannerLastSeen: bannerLastSeenRef.current });
       bannerLastSeenRef.current = null;
     }
   }, [updateAlerts]);
diff --git a/packages/shared/src/components/cards/collection/CollectionGrid.spec.tsx b/packages/shared/src/components/cards/collection/CollectionGrid.spec.tsx
index f6ac7df02b5..70ee1ebbedf 100644
--- a/packages/shared/src/components/cards/collection/CollectionGrid.spec.tsx
+++ b/packages/shared/src/components/cards/collection/CollectionGrid.spec.tsx
@@ -88,7 +88,7 @@ it('should call on share click on copy link button click', async () => {
 it('should not display publication date createdAt is empty', async () => {
   renderComponent({
     ...defaultProps,
-    post: { ...post, createdAt: null },
+    post: { ...post, createdAt: undefined },
   });
   const el = screen.queryByText('Jun 13, 2018');
   expect(el).not.toBeInTheDocument();
diff --git a/packages/shared/src/components/cards/common/Card.tsx b/packages/shared/src/components/cards/common/Card.tsx
index a988c942ecb..c3ccaf13ada 100644
--- a/packages/shared/src/components/cards/common/Card.tsx
+++ b/packages/shared/src/components/cards/common/Card.tsx
@@ -84,7 +84,7 @@ export const getPostClassNames = (
   ...postClassNames: string[]
 ): string =>
   classNames(
-    { [styles.read]: post.read, [styles.trending]: post.trending > 0 },
+    { [styles.read]: post.read, [styles.trending]: (post.trending ?? 0) > 0 },
     styles.post,
     'group',
     ...postClassNames,
diff --git a/packages/shared/src/components/cards/common/ClickbaitShield.tsx b/packages/shared/src/components/cards/common/ClickbaitShield.tsx
index 75f8d62a5e6..24dc30ae704 100644
--- a/packages/shared/src/components/cards/common/ClickbaitShield.tsx
+++ b/packages/shared/src/components/cards/common/ClickbaitShield.tsx
@@ -71,6 +71,12 @@ export const ClickbaitShield = ({ post }: { post: Post }): ReactElement => {
                   type: LazyModal.ClickbaitShield,
                 });
               } else {
+                if (!user) {
+                  throw new Error(
+                    'ClickbaitShield requires an authenticated user to edit feed settings',
+                  );
+                }
+
                 router.push(
                   `${webappUrl}feeds/${user.id}/edit?dview=${FeedSettingsMenu.AI}`,
                 );
diff --git a/packages/shared/src/components/cards/common/PostCardHeader.tsx b/packages/shared/src/components/cards/common/PostCardHeader.tsx
index c56dcdd59c6..ef129257a81 100644
--- a/packages/shared/src/components/cards/common/PostCardHeader.tsx
+++ b/packages/shared/src/components/cards/common/PostCardHeader.tsx
@@ -117,7 +117,7 @@ export const PostCardHeader = ({
                   content={getReadPostButtonText(post)}
                   className="mr-2"
                   variant={ButtonVariant.Primary}
-                  href={articleLink}
+                  href={articleLink ?? ''}
                   onClick={onReadArticleClick}
                   openNewTab={openNewTab}
                   icon={getReadPostButtonIcon(post)}
diff --git a/packages/shared/src/components/cards/common/PostSummary.tsx b/packages/shared/src/components/cards/common/PostSummary.tsx
index fa816567518..826930db26b 100644
--- a/packages/shared/src/components/cards/common/PostSummary.tsx
+++ b/packages/shared/src/components/cards/common/PostSummary.tsx
@@ -1,4 +1,4 @@
-import type { HTMLAttributes, ReactElement, RefObject } from 'react';
+import type { HTMLAttributes } from 'react';
 import React, { forwardRef } from 'react';
 import { SummaryContainer, TLDRText } from '../../utilities';
 import ShowMoreContent from './ShowMoreContent';
@@ -7,10 +7,10 @@ interface SummaryProps extends HTMLAttributes<HTMLDivElement> {
   summary: string;
 }
 
-function PostSummary(
-  { summary, ...props }: SummaryProps,
-  ref: RefObject<HTMLDivElement>,
-): ReactElement {
+const PostSummary: React.ForwardRefRenderFunction<
+  HTMLDivElement,
+  SummaryProps
+> = ({ summary, ...props }, ref) => {
   return (
     <SummaryContainer ref={ref} {...props}>
       <ShowMoreContent
@@ -22,6 +22,6 @@ function PostSummary(
       />
     </SummaryContainer>
   );
-}
+};
 
 export default forwardRef(PostSummary);
diff --git a/packages/shared/src/components/cards/common/SquadPostCardHeader.tsx b/packages/shared/src/components/cards/common/SquadPostCardHeader.tsx
index 047de352523..7e12a63376a 100644
--- a/packages/shared/src/components/cards/common/SquadPostCardHeader.tsx
+++ b/packages/shared/src/components/cards/common/SquadPostCardHeader.tsx
@@ -14,6 +14,7 @@ import { useBookmarkProvider } from '../../../hooks';
 import type { UserShortProfile } from '../../../lib/user';
 import { PostOptionButton } from '../../../features/posts/PostOptionButton';
 import { isSourceUserSource } from '../../../graphql/sources';
+import type { SourceTooltip } from '../../../graphql/sources';
 
 const UserEntityCard = dynamic(
   /* webpackChunkName: "userEntityCard" */ () =>
@@ -48,7 +49,7 @@ export const SquadPostCardHeader = ({
         <div className="relative flex w-full flex-row gap-2">
           {!isUserSource && (
             <SourceButton
-              source={source}
+              source={source as SourceTooltip}
               className={classNames(
                 'z-0',
                 !enableSourceHeader && 'absolute -bottom-2 -right-2',
diff --git a/packages/shared/src/components/cards/common/list/PostMetadata.tsx b/packages/shared/src/components/cards/common/list/PostMetadata.tsx
index 4be3c9e03b9..242f56020fb 100644
--- a/packages/shared/src/components/cards/common/list/PostMetadata.tsx
+++ b/packages/shared/src/components/cards/common/list/PostMetadata.tsx
@@ -30,7 +30,7 @@ export default function PostMetadata({
 }: PostMetadataProps): ReactElement {
   const { boostedBy } = useFeedCardContext();
   const promotedText = useScrambler(
-    boostedBy ? `Promoted by @${boostedBy.username}` : null,
+    boostedBy ? `Promoted by @${boostedBy.username}` : undefined,
   );
 
   return (
diff --git a/packages/shared/src/components/cards/common/list/SignalList.spec.tsx b/packages/shared/src/components/cards/common/list/SignalList.spec.tsx
index 359fac93aaf..4590d8337ec 100644
--- a/packages/shared/src/components/cards/common/list/SignalList.spec.tsx
+++ b/packages/shared/src/components/cards/common/list/SignalList.spec.tsx
@@ -5,7 +5,7 @@ import userEvent from '@testing-library/user-event';
 import type { NextRouter } from 'next/router';
 import { useRouter } from 'next/router';
 import { mocked } from 'ts-jest/utils';
-import type { Post, SharedPost } from '../../../../graphql/posts';
+import type { Post } from '../../../../graphql/posts';
 import { PostType } from '../../../../graphql/posts';
 import { TestBootProvider } from '../../../../../__tests__/helpers/boot';
 import { sharePost } from '../../../../../__tests__/fixture/post';
@@ -92,7 +92,7 @@ it('should render retweet content when tweet content is empty', async () => {
         ...sharePost.sharedPost,
         type: PostType.SocialTwitter,
         title: 'Retweet content should be shown',
-      } as SharedPost,
+      } as Post['sharedPost'],
     },
   });
 
diff --git a/packages/shared/src/components/cards/common/list/SignalList.tsx b/packages/shared/src/components/cards/common/list/SignalList.tsx
index ad98b7c9cbe..61db316e0e9 100644
--- a/packages/shared/src/components/cards/common/list/SignalList.tsx
+++ b/packages/shared/src/components/cards/common/list/SignalList.tsx
@@ -138,11 +138,12 @@ export const SignalList = forwardRef(function SignalList(
         type: typeLabel,
       }}
       linkProps={
-        !isFeedPreview && {
+        (!isFeedPreview && {
           title: resolvedTitle || post.title,
           href: post.commentsPermalink,
           onClick: onPostCardClick,
-        }
+        }) ||
+        undefined
       }
       bookmarked={post.bookmarked}
     >
diff --git a/packages/shared/src/components/cards/poll/PollOptions.tsx b/packages/shared/src/components/cards/poll/PollOptions.tsx
index fbdcfda77a0..5119214d326 100644
--- a/packages/shared/src/components/cards/poll/PollOptions.tsx
+++ b/packages/shared/src/components/cards/poll/PollOptions.tsx
@@ -119,7 +119,7 @@ export const PollOptionButtons = ({
   return options.map((option) => (
     <button
       disabled={isNullOrUndefined(onClick)}
-      onClick={() => onClick(option.id, option.text)}
+      onClick={() => onClick?.(option.id, option.text)}
       key={option.order}
       type="button"
       className="flex w-full flex-1 items-center justify-center rounded-12 border border-border-subtlest-tertiary p-2 text-center text-text-secondary typo-callout hover:bg-surface-hover"
diff --git a/packages/shared/src/components/cards/share/ShareList.spec.tsx b/packages/shared/src/components/cards/share/ShareList.spec.tsx
index efb9877c780..eee680dc580 100644
--- a/packages/shared/src/components/cards/share/ShareList.spec.tsx
+++ b/packages/shared/src/components/cards/share/ShareList.spec.tsx
@@ -32,7 +32,7 @@ const sharedTweetPost = {
     type: PostType.SocialTwitter,
     title: 'Referenced tweet body',
     source: {
-      ...sharePost.sharedPost.source,
+      ...(sharePost.sharedPost?.source ?? {}),
       handle: 'typescript',
       name: 'Typescript',
     },
diff --git a/packages/shared/src/components/cards/squad/common/useSquadsDirectoryLogging.ts b/packages/shared/src/components/cards/squad/common/useSquadsDirectoryLogging.ts
index e9414803189..1faf284040e 100644
--- a/packages/shared/src/components/cards/squad/common/useSquadsDirectoryLogging.ts
+++ b/packages/shared/src/components/cards/squad/common/useSquadsDirectoryLogging.ts
@@ -6,7 +6,7 @@ import { LogEvent } from '../../../../lib/log';
 import { OtherFeedPage } from '../../../../lib/query';
 import { useLogContext } from '../../../../contexts/LogContext';
 
-export const useSquadsDirectoryLogging = (ad: Ad) => {
+export const useSquadsDirectoryLogging = (ad?: Ad) => {
   const { ref, inView } = useInView({
     triggerOnce: true,
   });
@@ -16,6 +16,10 @@ export const useSquadsDirectoryLogging = (ad: Ad) => {
 
   const onLogAdEvent = useCallback(
     (action: LogEvent.Impression | LogEvent.Click) => {
+      if (!ad) {
+        throw new Error('Missing ad for squads directory logging');
+      }
+
       logEvent(adLogEvent(action, ad, feedLogExtra(OtherFeedPage.Squad)));
     },
     [ad, logEvent],
diff --git a/packages/shared/src/components/comments/CommentActionButtons.spec.tsx b/packages/shared/src/components/comments/CommentActionButtons.spec.tsx
index 3d9bf94289c..a3dc11cff03 100644
--- a/packages/shared/src/components/comments/CommentActionButtons.spec.tsx
+++ b/packages/shared/src/components/comments/CommentActionButtons.spec.tsx
@@ -39,7 +39,7 @@ beforeEach(() => {
 
 const renderComponent = (
   commentUpdate: Partial<Comment> = {},
-  user: LoggedUser = null,
+  user: LoggedUser = null as unknown as LoggedUser,
   mocks: MockedGraphQLResponse[] = [],
 ): RenderResult => {
   const props: Props = {
diff --git a/packages/shared/src/components/comments/CommentBox.tsx b/packages/shared/src/components/comments/CommentBox.tsx
index 22955b09ceb..f0d70249def 100644
--- a/packages/shared/src/components/comments/CommentBox.tsx
+++ b/packages/shared/src/components/comments/CommentBox.tsx
@@ -59,7 +59,7 @@ function CommentBox({
             post={post}
             comment={comment}
             origin={origin}
-            parentId={parentId}
+            parentId={parentId ?? null}
             onShare={onShare}
             onComment={onComment}
             onDelete={onDelete}
diff --git a/packages/shared/src/components/drawers/ListDrawer.tsx b/packages/shared/src/components/drawers/ListDrawer.tsx
index 502e1a24345..ac88bbb22be 100644
--- a/packages/shared/src/components/drawers/ListDrawer.tsx
+++ b/packages/shared/src/components/drawers/ListDrawer.tsx
@@ -30,7 +30,9 @@ export function ListDrawer({
   canFetchMore = false,
   isFetchingNextPage,
 }: ListDrawerProps): ReactElement {
-  const ref = React.useRef<DrawerRef>();
+  const ref = React.useRef<DrawerRef>(
+    null,
+  ) as React.MutableRefObject<DrawerRef>;
   const infiniteScrollRef = useFeedInfiniteScroll({
     fetchPage: fetchNextPage ?? (() => {}),
     canFetchMore: canFetchMore && !isFetchingNextPage,
diff --git a/packages/shared/src/components/drawers/NavDrawer.tsx b/packages/shared/src/components/drawers/NavDrawer.tsx
index 9b20608b993..60c87146d9a 100644
--- a/packages/shared/src/components/drawers/NavDrawer.tsx
+++ b/packages/shared/src/components/drawers/NavDrawer.tsx
@@ -39,7 +39,7 @@ export function NavDrawer({
 
   const router = useRouter();
   const canPurchaseCores = useCanPurchaseCores();
-  const ref = useRef<DrawerRef>();
+  const ref = useRef<DrawerRef>(null) as React.MutableRefObject<DrawerRef>;
 
   return (
     <Drawer
diff --git a/packages/shared/src/components/feeds/FeedSettings/FeedSettingsCreate.tsx b/packages/shared/src/components/feeds/FeedSettings/FeedSettingsCreate.tsx
index 03c7dfa7b79..533686ff05d 100644
--- a/packages/shared/src/components/feeds/FeedSettings/FeedSettingsCreate.tsx
+++ b/packages/shared/src/components/feeds/FeedSettings/FeedSettingsCreate.tsx
@@ -253,7 +253,7 @@ export const FeedSettingsCreate = (): ReactElement => {
 
   const createdFeedId = createdFeedData?.id;
 
-  if (!newFeedId) {
+  if (!createdFeedId) {
     return (
       <Modal isOpen kind={Modal.Kind.FixedCenter} size={Modal.Size.Small}>
         <Modal.Body className="items-center justify-center">
diff --git a/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEdit.tsx b/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEdit.tsx
index 8d065c91ae3..77267cfdffd 100644
--- a/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEdit.tsx
+++ b/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEdit.tsx
@@ -109,7 +109,7 @@ type TabOptions = {
 
 export const FeedSettingsEdit = (
   props: FeedSettingsEditProps,
-): ReactElement => {
+): ReactElement | null => {
   const router = useRouter();
   const feedSettingsEditContext = useFeedSettingsEdit(props);
   const { feed, onBackToFeed, onDiscard } = feedSettingsEditContext;
diff --git a/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEditContext.tsx b/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEditContext.tsx
index 8f7ba211752..23c0c1ab358 100644
--- a/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEditContext.tsx
+++ b/packages/shared/src/components/feeds/FeedSettings/FeedSettingsEditContext.tsx
@@ -2,7 +2,9 @@ import { createContext, useContext } from 'react';
 import type { FeedSettingsEditContextValue } from './types';
 
 export const FeedSettingsEditContext =
-  createContext<FeedSettingsEditContextValue>(undefined);
+  createContext<FeedSettingsEditContextValue>(
+    undefined as unknown as FeedSettingsEditContextValue,
+  );
 
 export const useFeedSettingsEditContext = (): FeedSettingsEditContextValue =>
   useContext(FeedSettingsEditContext);
diff --git a/packages/shared/src/components/feeds/FeedSettings/components/SmartPrompts.tsx b/packages/shared/src/components/feeds/FeedSettings/components/SmartPrompts.tsx
index ff236ab42b5..d25e46b5293 100644
--- a/packages/shared/src/components/feeds/FeedSettings/components/SmartPrompts.tsx
+++ b/packages/shared/src/components/feeds/FeedSettings/components/SmartPrompts.tsx
@@ -24,7 +24,7 @@ export const SmartPrompts = (): ReactElement => {
   const { displayToast } = useToastNotification();
   const { logEvent } = useLogContext();
   const { flags, updatePromptFlag } = useSettingsContext();
-  const { prompt: promptFlags } = flags;
+  const promptFlags = flags?.prompt;
   const { data: prompts, isLoading } = usePromptsQuery();
 
   return (
diff --git a/packages/shared/src/components/feeds/FeedSettings/types.ts b/packages/shared/src/components/feeds/FeedSettings/types.ts
index a0379c6925b..9250efcfad4 100644
--- a/packages/shared/src/components/feeds/FeedSettings/types.ts
+++ b/packages/shared/src/components/feeds/FeedSettings/types.ts
@@ -5,7 +5,7 @@ export type FeedSettingsFormData = {
   name: string;
   icon?: string;
 } & Pick<
-  Feed['flags'],
+  NonNullable<Feed['flags']>,
   | 'orderBy'
   | 'minDayRange'
   | 'minUpvotes'
diff --git a/packages/shared/src/components/layout/HeaderButtons.spec.tsx b/packages/shared/src/components/layout/HeaderButtons.spec.tsx
index 112a32036a4..185224f3f36 100644
--- a/packages/shared/src/components/layout/HeaderButtons.spec.tsx
+++ b/packages/shared/src/components/layout/HeaderButtons.spec.tsx
@@ -2,7 +2,7 @@ import type { ReactElement } from 'react';
 import React from 'react';
 import { QueryClient } from '@tanstack/react-query';
 import { render, screen } from '@testing-library/react';
-import { GrowthBook } from '@growthbook/growthbook';
+import { GrowthBook } from '@growthbook/growthbook-react';
 import { TestBootProvider } from '../../../__tests__/helpers/boot';
 import { HeaderButtons } from './HeaderButtons';
 
diff --git a/packages/shared/src/components/marketingCta/MarketingCtaPopoverSmall.tsx b/packages/shared/src/components/marketingCta/MarketingCtaPopoverSmall.tsx
index 9b813818daa..002a028f2a4 100644
--- a/packages/shared/src/components/marketingCta/MarketingCtaPopoverSmall.tsx
+++ b/packages/shared/src/components/marketingCta/MarketingCtaPopoverSmall.tsx
@@ -104,7 +104,7 @@ export function MarketingCtaPopoverSmall({
           className={classNames(
             isMobile ? 'mb-4 w-full' : 'absolute right-2 top-2 z-1',
           )}
-          icon={!isMobile && <MiniCloseIcon />}
+          icon={(!isMobile && <MiniCloseIcon />) || undefined}
           onClick={onCtaDismiss}
         >
           {isMobile ? 'Close' : null}
diff --git a/packages/shared/src/components/marketingCta/common.tsx b/packages/shared/src/components/marketingCta/common.tsx
index fe7940ad9fd..8da58d96480 100644
--- a/packages/shared/src/components/marketingCta/common.tsx
+++ b/packages/shared/src/components/marketingCta/common.tsx
@@ -80,7 +80,7 @@ export const Header = ({
       label={tagText}
       className={tagColorMap[tagColor || 'avocado']}
       size={PillSize.Small}
-      alignment={null}
+      alignment={undefined}
     />
     <Button
       className="ml-auto"
diff --git a/packages/shared/src/components/modals/AchievementCompletionModal.tsx b/packages/shared/src/components/modals/AchievementCompletionModal.tsx
index cb8d5b9b48f..4c4a092daff 100644
--- a/packages/shared/src/components/modals/AchievementCompletionModal.tsx
+++ b/packages/shared/src/components/modals/AchievementCompletionModal.tsx
@@ -11,7 +11,7 @@ import { useProfileAchievements } from '../../hooks/profile/useProfileAchievemen
 import { useTrackedAchievement } from '../../hooks/profile/useTrackedAchievement';
 import { ActionType } from '../../graphql/actions';
 import { LogEvent, TargetType } from '../../lib/log';
-import type { ModalProps } from './common/Modal';
+import type { LazyModalCommonProps, ModalProps } from './common/Modal';
 import { Modal } from './common/Modal';
 import { ModalClose } from './common/ModalClose';
 import {
@@ -35,9 +35,11 @@ const sparkles = Array.from({ length: 60 }, (_, i) => ({
   size: 3 + ((i * 7) % 5),
 }));
 
-interface AchievementCompletionModalProps extends ModalProps {
+interface AchievementCompletionModalProps
+  extends Omit<ModalProps, 'onRequestClose'> {
   achievementId: string;
   onAfterClose?: () => void;
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
 }
 
 export const AchievementCompletionModal = ({
diff --git a/packages/shared/src/components/modals/FeedbackModal.tsx b/packages/shared/src/components/modals/FeedbackModal.tsx
index 0bfe69cd4b9..2d7cde0d9b8 100644
--- a/packages/shared/src/components/modals/FeedbackModal.tsx
+++ b/packages/shared/src/components/modals/FeedbackModal.tsx
@@ -1,7 +1,7 @@
 import type { ReactElement, ChangeEvent } from 'react';
 import React, { useState, useCallback, useRef, useEffect } from 'react';
 import { useMutation } from '@tanstack/react-query';
-import type { ModalProps } from './common/Modal';
+import type { LazyModalCommonProps, ModalProps } from './common/Modal';
 import { Modal } from './common/Modal';
 import { ModalSize } from './common/types';
 import { Button, ButtonVariant, ButtonSize } from '../buttons/Button';
@@ -29,6 +29,9 @@ import {
 import { useSettingsContext } from '../../contexts/SettingsContext';
 
 const FEEDBACK_MAX_LENGTH = 2000;
+type FeedbackModalProps = Omit<ModalProps, 'onRequestClose'> & {
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
+};
 
 const categoryOptions: { value: FeedbackCategory; label: string }[] = [
   { value: FeedbackCategory.BugReport, label: 'Bug Report' },
@@ -41,7 +44,7 @@ const categoryOptions: { value: FeedbackCategory; label: string }[] = [
 const FeedbackModal = ({
   onRequestClose,
   ...props
-}: ModalProps): ReactElement => {
+}: FeedbackModalProps): ReactElement => {
   const { displayToast } = useToastNotification();
   const { themeMode } = useSettingsContext();
   const fileInputRef = useRef<HTMLInputElement>(null);
@@ -159,7 +162,7 @@ const FeedbackModal = ({
     mutationFn: (input: FeedbackInput) => submitFeedback(input),
     onSuccess: () => {
       displayToast('Thank you for your feedback!');
-      onRequestClose?.(null);
+      onRequestClose?.(undefined);
     },
     onError: () => {
       hasSubmitted.current = false;
diff --git a/packages/shared/src/components/modals/JobOpportunityModal.tsx b/packages/shared/src/components/modals/JobOpportunityModal.tsx
index 3ba5d332df8..2501b8dc1e4 100644
--- a/packages/shared/src/components/modals/JobOpportunityModal.tsx
+++ b/packages/shared/src/components/modals/JobOpportunityModal.tsx
@@ -32,7 +32,7 @@ export const JobOpportunityModal = ({
 
   const onClick = (event: MouseEvent) => {
     logOpportunityNudgeClick();
-    onRequestClose(event);
+    onRequestClose?.(event);
   };
 
   return (
diff --git a/packages/shared/src/components/modals/RepostsModal.tsx b/packages/shared/src/components/modals/RepostsModal.tsx
index ba7e0a55ec8..777031ab682 100644
--- a/packages/shared/src/components/modals/RepostsModal.tsx
+++ b/packages/shared/src/components/modals/RepostsModal.tsx
@@ -24,6 +24,11 @@ export function RepostsModal({
   const container = useRef<HTMLElement>(null);
   const modalRef = useRef<HTMLElement | null>(null);
   const { requestMethod } = useRequestProtocol();
+
+  if (!requestMethod) {
+    throw new Error('Request method is required in RepostsModal');
+  }
+
   const queryResult = useInfiniteQuery({
     queryKey,
     queryFn: ({ pageParam }) =>
diff --git a/packages/shared/src/components/modals/ReputationPrivilegesModal.tsx b/packages/shared/src/components/modals/ReputationPrivilegesModal.tsx
index 69755c42afb..144f88af1b7 100644
--- a/packages/shared/src/components/modals/ReputationPrivilegesModal.tsx
+++ b/packages/shared/src/components/modals/ReputationPrivilegesModal.tsx
@@ -20,7 +20,7 @@ export const ReputationPrivilegesModal = ({
   const onClose = (event: MouseEvent) => {
     completeAction(ActionType.AckRep250);
 
-    onRequestClose(event);
+    onRequestClose?.(event);
   };
 
   return (
diff --git a/packages/shared/src/components/modals/SharedBookmarksModal.spec.tsx b/packages/shared/src/components/modals/SharedBookmarksModal.spec.tsx
index 66358edc5e2..f761679e818 100644
--- a/packages/shared/src/components/modals/SharedBookmarksModal.spec.tsx
+++ b/packages/shared/src/components/modals/SharedBookmarksModal.spec.tsx
@@ -89,7 +89,7 @@ it('should enable public mode on toggle click', async () => {
   const checkboxes = await screen.findAllByRole('checkbox');
   const checkbox = checkboxes.find((el) =>
     // eslint-disable-next-line testing-library/no-node-access, testing-library/prefer-screen-queries
-    queryByText(el.parentElement, 'Public mode'),
+    el.parentElement ? queryByText(el.parentElement, 'Public mode') : null,
   ) as HTMLInputElement;
   fireEvent.click(checkbox);
   await waitForNock();
diff --git a/packages/shared/src/components/modals/SquadTourModal.tsx b/packages/shared/src/components/modals/SquadTourModal.tsx
index e9a9b743481..6e1a6dcac8b 100644
--- a/packages/shared/src/components/modals/SquadTourModal.tsx
+++ b/packages/shared/src/components/modals/SquadTourModal.tsx
@@ -1,16 +1,20 @@
 import type { ReactElement } from 'react';
 import React from 'react';
 import SquadTour from '../squads/SquadTour';
-import type { ModalProps } from './common/Modal';
+import type { LazyModalCommonProps, ModalProps } from './common/Modal';
 import { Modal } from './common/Modal';
 import { ButtonSize, ButtonVariant } from '../buttons/Button';
 import { useSquadTour } from '../../hooks/useSquadTour';
 import { ModalClose } from './common/ModalClose';
 
+type SquadTourModalProps = Omit<ModalProps, 'onRequestClose'> & {
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
+};
+
 function SquadTourModal({
   onRequestClose,
   ...props
-}: ModalProps): ReactElement {
+}: SquadTourModalProps): ReactElement {
   const { onCloseTour } = useSquadTour();
   const onModalClose: typeof onRequestClose = (param) => {
     onCloseTour();
@@ -27,7 +31,7 @@ function SquadTourModal({
       isDrawerOnMobile
       drawerProps={{ className: { drawer: 'pb-4', close: 'mx-4' } }}
     >
-      <SquadTour onClose={() => onModalClose(null)} />
+      <SquadTour onClose={() => onModalClose(undefined)} />
       <ModalClose
         size={ButtonSize.Small}
         variant={ButtonVariant.Secondary}
diff --git a/packages/shared/src/components/modals/UserListModal.tsx b/packages/shared/src/components/modals/UserListModal.tsx
index 80c5b17b8a4..faae77f8c13 100644
--- a/packages/shared/src/components/modals/UserListModal.tsx
+++ b/packages/shared/src/components/modals/UserListModal.tsx
@@ -47,7 +47,9 @@ function UserListModal({
   children,
   ...props
 }: UserListModalProps): ReactElement {
-  const container = useRef<HTMLElement>();
+  const container = useRef<HTMLElement>(
+    null,
+  ) as React.MutableRefObject<HTMLElement>;
   const [modalRef, setModalRef] = useState<HTMLElement>();
 
   const { onScroll, ...otherScrollingProps } = scrollingProps;
diff --git a/packages/shared/src/components/modals/bookmark/BookmarkFolderModal.tsx b/packages/shared/src/components/modals/bookmark/BookmarkFolderModal.tsx
index 1b547f966b3..72cf1dd6ab6 100644
--- a/packages/shared/src/components/modals/bookmark/BookmarkFolderModal.tsx
+++ b/packages/shared/src/components/modals/bookmark/BookmarkFolderModal.tsx
@@ -70,7 +70,7 @@ const BookmarkFolderModal = ({
     if (shouldUpgrade) {
       return;
     }
-    onSubmit?.({ ...folder, name, icon });
+    onSubmit?.({ ...folder, name, icon } as BookmarkFolder);
   };
 
   return (
diff --git a/packages/shared/src/components/modals/common/ModalBody.tsx b/packages/shared/src/components/modals/common/ModalBody.tsx
index 78946dd3643..cffdb396063 100644
--- a/packages/shared/src/components/modals/common/ModalBody.tsx
+++ b/packages/shared/src/components/modals/common/ModalBody.tsx
@@ -1,5 +1,5 @@
 import classNames from 'classnames';
-import type { MutableRefObject, ReactElement, ReactNode } from 'react';
+import type { ReactElement, ReactNode } from 'react';
 import React, { forwardRef, useContext } from 'react';
 import { ModalKind, ModalPropsContext, ModalSize } from './types';
 
@@ -13,7 +13,7 @@ const bigModals = [ModalSize.Large, ModalSize.XLarge];
 
 function ModalBodyComponent(
   { children, className, view, ...props }: ModalBodyProps,
-  ref: MutableRefObject<HTMLElement>,
+  ref: React.Ref<HTMLElement>,
 ): ReactElement | null {
   const { activeView, kind, size, isDrawer } = useContext(ModalPropsContext);
   const sectionClassName = classNames(
diff --git a/packages/shared/src/components/modals/hotTakes/HotAndColdModal.tsx b/packages/shared/src/components/modals/hotTakes/HotAndColdModal.tsx
index 8feda81e29f..1f5a6b3a5cc 100644
--- a/packages/shared/src/components/modals/hotTakes/HotAndColdModal.tsx
+++ b/packages/shared/src/components/modals/hotTakes/HotAndColdModal.tsx
@@ -781,7 +781,7 @@ const HotTakeCard = ({
             </div>
             <div className="flex gap-2">
               <ReputationUserBadge user={hotTake.user} disableTooltip />
-              {hotTake.user.companies?.length > 0 && (
+              {(hotTake.user.companies?.length ?? 0) > 0 && (
                 <VerifiedCompanyUserBadge
                   user={{ companies: hotTake.user.companies }}
                 />
diff --git a/packages/shared/src/components/modals/plus/MobileSmartPromptsModal.tsx b/packages/shared/src/components/modals/plus/MobileSmartPromptsModal.tsx
index 9c735b595cc..3bdf6ceb2ac 100644
--- a/packages/shared/src/components/modals/plus/MobileSmartPromptsModal.tsx
+++ b/packages/shared/src/components/modals/plus/MobileSmartPromptsModal.tsx
@@ -42,7 +42,7 @@ export const MobileSmartPromptsModal = ({
             size={ButtonSize.Medium}
             variant={ButtonVariant.Option}
             key={id}
-            flags={flags}
+            flags={flags ?? {}}
             onClick={(event) => onClick(event, id)}
           >
             {label}
diff --git a/packages/shared/src/components/modals/post/ReadingHistoryModal.tsx b/packages/shared/src/components/modals/post/ReadingHistoryModal.tsx
index 7635717369b..31d4f0ec943 100644
--- a/packages/shared/src/components/modals/post/ReadingHistoryModal.tsx
+++ b/packages/shared/src/components/modals/post/ReadingHistoryModal.tsx
@@ -33,7 +33,7 @@ export function ReadingHistoryModal({
   const onClick = (e: React.MouseEvent, post: PostItem) => {
     onArticleSelected(post);
     if (!keepOpenAfterSelecting) {
-      onRequestClose(e);
+      onRequestClose?.(e);
     }
   };
 
diff --git a/packages/shared/src/components/modals/referral/GenericReferralModal.tsx b/packages/shared/src/components/modals/referral/GenericReferralModal.tsx
index 62b16afbcb4..3be2fba37e8 100644
--- a/packages/shared/src/components/modals/referral/GenericReferralModal.tsx
+++ b/packages/shared/src/components/modals/referral/GenericReferralModal.tsx
@@ -32,7 +32,7 @@ function GenericReferralModal({
 
   useEffect(() => {
     if (!isLogged.current) {
-      updateLastReferralReminder();
+      updateLastReferralReminder?.();
       isLogged.current = true;
       logEvent({
         event_name: LogEvent.Impression,
diff --git a/packages/shared/src/components/modals/report/ReportCommentModal.tsx b/packages/shared/src/components/modals/report/ReportCommentModal.tsx
index 04535bd7123..1fe7a682747 100644
--- a/packages/shared/src/components/modals/report/ReportCommentModal.tsx
+++ b/packages/shared/src/components/modals/report/ReportCommentModal.tsx
@@ -62,7 +62,7 @@ export function ReportCommentModal({
       onReport(comment);
     }
 
-    props.onRequestClose(event);
+    props.onRequestClose?.(event);
   };
 
   return (
diff --git a/packages/shared/src/components/modals/squads/PrivilegedMembersModal.tsx b/packages/shared/src/components/modals/squads/PrivilegedMembersModal.tsx
index 98627f43fec..598e372de5e 100644
--- a/packages/shared/src/components/modals/squads/PrivilegedMembersModal.tsx
+++ b/packages/shared/src/components/modals/squads/PrivilegedMembersModal.tsx
@@ -32,7 +32,7 @@ function PrivilegedMembersModal({
     <Modal kind={Modal.Kind.FlexibleCenter} size={Modal.Size.Medium} {...props}>
       <Modal.Header title="Moderated by" />
       <Modal.Body className="!p-0">
-        {squad.privilegedMembers?.map(({ user, role }) => (
+        {squad?.privilegedMembers?.map(({ user, role }) => (
           <Link key={user.username} href={user.permalink}>
             <UserShortInfo
               tag="a"
diff --git a/packages/shared/src/components/onboarding/EditTag.tsx b/packages/shared/src/components/onboarding/EditTag.tsx
index 6e53fc57496..b74099cf4e7 100644
--- a/packages/shared/src/components/onboarding/EditTag.tsx
+++ b/packages/shared/src/components/onboarding/EditTag.tsx
@@ -33,8 +33,8 @@ export const EditTag = ({
   const isPreviewEnabled = tagsCount >= requiredTags;
 
   const [searchQuery, setSearchQuery] = useState<string>('');
-  const [onSearch] = useDebounceFn((value: string) => {
-    setSearchQuery(value);
+  const [onSearch] = useDebounceFn((value?: string) => {
+    setSearchQuery(value ?? '');
   }, 350);
 
   const { data: searchResult } = useTagSearch({
diff --git a/packages/shared/src/components/opportunity/InlineEditor/InlineContentEditor.tsx b/packages/shared/src/components/opportunity/InlineEditor/InlineContentEditor.tsx
index d3208806f8d..d90a46b834a 100644
--- a/packages/shared/src/components/opportunity/InlineEditor/InlineContentEditor.tsx
+++ b/packages/shared/src/components/opportunity/InlineEditor/InlineContentEditor.tsx
@@ -45,7 +45,9 @@ export const InlineContentEditor = ({
   isRequired = false,
 }: InlineContentEditorProps): ReactElement => {
   const { displayToast } = useToastNotification();
-  const richTextRef = useRef<RichTextRef>();
+  const richTextRef = useRef<RichTextRef>(
+    null,
+  ) as React.MutableRefObject<RichTextRef>;
 
   const { data: opportunity, promise } = useQuery({
     ...opportunityByIdOptions({ id: opportunityId }),
diff --git a/packages/shared/src/components/opportunity/NewOpportunityPopover.tsx b/packages/shared/src/components/opportunity/NewOpportunityPopover.tsx
index e2c01ec1b7d..6bbd2d386ce 100644
--- a/packages/shared/src/components/opportunity/NewOpportunityPopover.tsx
+++ b/packages/shared/src/components/opportunity/NewOpportunityPopover.tsx
@@ -49,8 +49,8 @@ export const NewOpportunityPopover = (): ReactElement => {
           type={TypographyType.Subhead}
           color={TypographyColor.Primary}
         >
-          Hey {user.name}, We&#39;ve found a new opportunity that aligns with
-          your experience and what you’ve been exploring lately.
+          Hey {user?.name ?? 'there'}, We&#39;ve found a new opportunity that
+          aligns with your experience and what you’ve been exploring lately.
         </Typography>
         <Link href={`${webappUrl}jobs/${alerts.opportunityId}`} passHref>
           <Button
diff --git a/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityEditRecruiterModal.tsx b/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityEditRecruiterModal.tsx
index 332fe920f90..6038e7c64de 100644
--- a/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityEditRecruiterModal.tsx
+++ b/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityEditRecruiterModal.tsx
@@ -3,7 +3,10 @@ import { useMutation, useQuery } from '@tanstack/react-query';
 import { useForm } from 'react-hook-form';
 import { zodResolver } from '@hookform/resolvers/zod';
 import z from 'zod';
-import type { ModalProps } from '../../modals/common/Modal';
+import type {
+  LazyModalCommonProps,
+  ModalProps,
+} from '../../modals/common/Modal';
 import { Modal } from '../../modals/common/Modal';
 import { TextField } from '../../fields/TextField';
 import { opportunityByIdOptions } from '../../../features/opportunity/queries';
@@ -33,13 +36,15 @@ export const opportunityEditRecruiterSchema = z.object({
 export type OpportunityEditRecruiterModalProps = {
   id: string;
   recruiterId?: string;
-};
+} & Omit<ModalProps, 'onRequestClose'> & {
+    onRequestClose?: LazyModalCommonProps['onRequestClose'];
+  };
 
 export const OpportunityEditRecruiterModal = ({
   id,
   recruiterId,
   ...rest
-}: OpportunityEditRecruiterModalProps & ModalProps) => {
+}: OpportunityEditRecruiterModalProps) => {
   const { displayToast } = useToastNotification();
   const { data: opportunity, promise } = useQuery({
     ...opportunityByIdOptions({ id }),
@@ -53,7 +58,7 @@ export const OpportunityEditRecruiterModal = ({
     onSuccess: (result) => {
       updateOpportunity(result);
 
-      rest.onRequestClose?.(null);
+      rest.onRequestClose?.(undefined);
     },
   });
 
diff --git a/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityReimportModal.tsx b/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityReimportModal.tsx
index ffa040aa301..61186eab0c5 100644
--- a/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityReimportModal.tsx
+++ b/packages/shared/src/components/opportunity/OpportunityEditModal/OpportunityReimportModal.tsx
@@ -2,7 +2,10 @@ import type { ReactElement } from 'react';
 import React, { useState, useCallback } from 'react';
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import z from 'zod';
-import type { ModalProps } from '../../modals/common/Modal';
+import type {
+  LazyModalCommonProps,
+  ModalProps,
+} from '../../modals/common/Modal';
 import { Modal } from '../../modals/common/Modal';
 import {
   Typography,
@@ -19,8 +22,10 @@ import { getOpportunityByIdKey } from '../../../features/opportunity/queries';
 
 const jobLinkSchema = z.url({ message: 'Please enter a valid URL' });
 
-export interface OpportunityReimportModalProps extends ModalProps {
+export interface OpportunityReimportModalProps
+  extends Omit<ModalProps, 'onRequestClose'> {
   opportunityId: string;
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
 }
 
 const fileValidation = {
@@ -47,7 +52,7 @@ export const OpportunityReimportModal = ({
     onSuccess: (data) => {
       // Immediately update the cache with the returned data
       queryClient.setQueryData(getOpportunityByIdKey(opportunityId), data);
-      onRequestClose?.(null);
+      onRequestClose?.(undefined);
     },
     onError: (err) => {
       setError(err?.message || 'Failed to reimport. Please try again.');
diff --git a/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsInfo.tsx b/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsInfo.tsx
index 56c59b13ca0..9bd7454c84a 100644
--- a/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsInfo.tsx
+++ b/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsInfo.tsx
@@ -3,6 +3,7 @@ import React from 'react';
 import { useMutation, useQuery } from '@tanstack/react-query';
 import { useRouter } from 'next/router';
 import { recommendOpportunityScreeningQuestionsOptions } from '../../../features/opportunity/mutations';
+import type { Opportunity } from '../../../features/opportunity/types';
 import { opportunityByIdOptions } from '../../../features/opportunity/queries';
 import {
   ToastSubject,
@@ -59,7 +60,7 @@ export const OpportunityStepsInfo = (
       });
     },
     onSuccess: (data) => {
-      updateOpportunity({ ...opportunity, questions: data });
+      updateOpportunity({ ...opportunity, questions: data } as Opportunity);
 
       goToNextStep();
     },
diff --git a/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsQuestions.tsx b/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsQuestions.tsx
index c223f877599..f3d85d441c9 100644
--- a/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsQuestions.tsx
+++ b/packages/shared/src/components/opportunity/OpportunitySteps/OpportunityStepsQuestions.tsx
@@ -81,7 +81,7 @@ export const OpportunityStepsQuestions = (
               </ul>
             </div>
           ),
-          cancelButton: null,
+          cancelButton: undefined,
         });
 
         return;
diff --git a/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditForm.tsx b/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditForm.tsx
index 67bee626d6d..93b46f6f25d 100644
--- a/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditForm.tsx
+++ b/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditForm.tsx
@@ -4,7 +4,10 @@ import { useForm } from 'react-hook-form';
 import type { UseFormReturn } from 'react-hook-form';
 import { zodResolver } from '@hookform/resolvers/zod';
 import { z } from 'zod';
-import type { Opportunity } from '../../../../features/opportunity/types';
+import type {
+  Opportunity,
+  OpportunityLocation,
+} from '../../../../features/opportunity/types';
 import { OpportunityState } from '../../../../features/opportunity/protobuf/opportunity';
 import {
   opportunityEditInfoSchema,
@@ -130,13 +133,13 @@ export function formDataToPreviewOpportunity(
     locations:
       formData.locations?.map((loc) => ({
         type: formData.locationType,
-        location: loc.locationData
+        location: (loc.locationData
           ? {
               city: loc.locationData.city,
               country: loc.locationData.country,
               subdivision: loc.locationData.subdivision,
             }
-          : null,
+          : {}) as OpportunityLocation,
       })) || [],
     meta: formData.meta
       ? {
diff --git a/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditPageSetup.ts b/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditPageSetup.ts
index a70b1f2c961..c8191054162 100644
--- a/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditPageSetup.ts
+++ b/packages/shared/src/components/opportunity/SideBySideEdit/hooks/useOpportunityEditPageSetup.ts
@@ -74,7 +74,11 @@ export function useOpportunityEditPageSetup({
       ),
     onSuccess: () => {
       queryClient.invalidateQueries({
-        queryKey: generateQueryKey(RequestKey.Opportunity, null, opportunityId),
+        queryKey: generateQueryKey(
+          RequestKey.Opportunity,
+          undefined,
+          opportunityId,
+        ),
       });
     },
   });
diff --git a/packages/shared/src/components/organization/OrganizationEditForm.tsx b/packages/shared/src/components/organization/OrganizationEditForm.tsx
index 75ebae436b1..ff5d90431a0 100644
--- a/packages/shared/src/components/organization/OrganizationEditForm.tsx
+++ b/packages/shared/src/components/organization/OrganizationEditForm.tsx
@@ -164,7 +164,7 @@ export const OrganizationEditForm = ({
         onImageChange={handleImageChange}
         locationOptions={
           locationOptions?.map((loc) => ({
-            label: locationToString(loc),
+            label: locationToString(loc) ?? '',
             value: loc.id,
           })) || []
         }
diff --git a/packages/shared/src/components/plus/GiftUserContext.tsx b/packages/shared/src/components/plus/GiftUserContext.tsx
index 53d40db60c9..78436af52ad 100644
--- a/packages/shared/src/components/plus/GiftUserContext.tsx
+++ b/packages/shared/src/components/plus/GiftUserContext.tsx
@@ -4,7 +4,9 @@ import type { UserShortProfile } from '../../lib/user';
 export interface GiftUserContextData {
   giftToUser?: UserShortProfile;
 }
-export const GiftUserContext = createContext<GiftUserContextData | null>({});
+export const GiftUserContext = createContext<GiftUserContextData>(
+  {} as GiftUserContextData,
+);
 
 export const useGiftUserContext = (): GiftUserContextData =>
   useContext(GiftUserContext);
diff --git a/packages/shared/src/components/plus/PlusAdjustQuantity.tsx b/packages/shared/src/components/plus/PlusAdjustQuantity.tsx
index 72d8511a333..1d900eb8c65 100644
--- a/packages/shared/src/components/plus/PlusAdjustQuantity.tsx
+++ b/packages/shared/src/components/plus/PlusAdjustQuantity.tsx
@@ -80,7 +80,7 @@ export const PlusAdjustQuantity = ({
 
       <div className="flex gap-1">
         <TextField
-          label={null}
+          label=""
           inputId="team-size"
           value={itemQuantity}
           type="number"
diff --git a/packages/shared/src/components/plus/PlusExtension.tsx b/packages/shared/src/components/plus/PlusExtension.tsx
index 26cf764427a..031ce6d0835 100644
--- a/packages/shared/src/components/plus/PlusExtension.tsx
+++ b/packages/shared/src/components/plus/PlusExtension.tsx
@@ -20,6 +20,10 @@ const PlusExtension = (): ReactElement => {
   const { productOptions } = usePaymentContext();
 
   const handleClick = () => {
+    if (!marketingCta?.campaignId) {
+      throw new Error('PlusExtension requires a marketing CTA campaign id');
+    }
+
     logEvent({
       event_name: LogEvent.UpgradeSubscription,
       target_type: TargetType.MarketingCtaPlus,
diff --git a/packages/shared/src/components/plus/PlusListItem.tsx b/packages/shared/src/components/plus/PlusListItem.tsx
index 772621dbf2a..1efffa44b5c 100644
--- a/packages/shared/src/components/plus/PlusListItem.tsx
+++ b/packages/shared/src/components/plus/PlusListItem.tsx
@@ -1,4 +1,4 @@
-import type { FC, ReactElement } from 'react';
+import type { FC, ReactElement, ReactNode } from 'react';
 import React from 'react';
 import classNames from 'classnames';
 import ConditionalWrapper from '../ConditionalWrapper';
@@ -56,7 +56,7 @@ export const PlusListItem = ({
   return (
     <ConditionalWrapper
       condition={!!item.tooltip}
-      wrapper={(component: ReactElement) => (
+      wrapper={(component: ReactNode) => (
         <Tooltip
           className="!tablet:max-w-72 !max-w-full text-center"
           content={item.tooltip}
diff --git a/packages/shared/src/components/plus/PlusMarketingModal.tsx b/packages/shared/src/components/plus/PlusMarketingModal.tsx
index 1184e0c8db7..87b2a6a0d43 100644
--- a/packages/shared/src/components/plus/PlusMarketingModal.tsx
+++ b/packages/shared/src/components/plus/PlusMarketingModal.tsx
@@ -41,6 +41,10 @@ const PlusMarketingModal = (modalProps: ModalProps): ReactElement => {
   const isTablet = useViewSize(ViewSize.Tablet);
 
   const handleClose = () => {
+    if (!campaignId) {
+      throw new Error('PlusMarketingModal requires a campaign id');
+    }
+
     logEvent({
       event_name: LogEvent.MarketingCtaDismiss,
       target_type: TargetType.MarketingCtaPlus,
diff --git a/packages/shared/src/components/plus/PlusProductList.tsx b/packages/shared/src/components/plus/PlusProductList.tsx
index f90068c0a4d..84cb2e1afb5 100644
--- a/packages/shared/src/components/plus/PlusProductList.tsx
+++ b/packages/shared/src/components/plus/PlusProductList.tsx
@@ -44,7 +44,7 @@ const PlusProductList = ({
           value={priceId}
           checked={selected === priceId}
           onChange={() => {
-            onChange(priceId);
+            onChange?.(priceId);
             logSubscriptionEvent({
               event_name: LogEvent.SelectBillingCycle,
               target_id: metadata.title.toLowerCase(),
diff --git a/packages/shared/src/components/plus/PostUpgradeToPlus.tsx b/packages/shared/src/components/plus/PostUpgradeToPlus.tsx
index d1d7cde91e1..3b47ab7af05 100644
--- a/packages/shared/src/components/plus/PostUpgradeToPlus.tsx
+++ b/packages/shared/src/components/plus/PostUpgradeToPlus.tsx
@@ -31,7 +31,7 @@ export const PostUpgradeToPlus = ({
   children,
   className,
   onClose,
-}: PostUpgradeToPlusProps & PropsWithChildren): ReactElement => {
+}: PostUpgradeToPlusProps & PropsWithChildren): ReactElement | null => {
   const [show, setShow] = useState(true);
   const { logSubscriptionEvent, isPlus } = usePlusSubscription();
   const {
diff --git a/packages/shared/src/components/popover/GifPopover.tsx b/packages/shared/src/components/popover/GifPopover.tsx
index e3743d0b1db..608c4b9edd1 100644
--- a/packages/shared/src/components/popover/GifPopover.tsx
+++ b/packages/shared/src/components/popover/GifPopover.tsx
@@ -161,7 +161,7 @@ const GifPopover = ({
     0, 0,
   ]);
   const [debounceQuery] = useDebounceFn<string>(
-    (value) => setQuery(value),
+    (value) => setQuery(value ?? ''),
     500,
   );
   const {
diff --git a/packages/shared/src/components/post/BasePostContent.tsx b/packages/shared/src/components/post/BasePostContent.tsx
index f414ac479d2..0e1d81a904b 100644
--- a/packages/shared/src/components/post/BasePostContent.tsx
+++ b/packages/shared/src/components/post/BasePostContent.tsx
@@ -35,11 +35,17 @@ export function BasePostContent({
 }: BasePostContentProps): ReactElement {
   const { id } = post ?? {};
   const { onCopyPostLink } = engagementProps ?? {};
+  const postPageNavigationProps = isPostPage ? navigationProps : undefined;
+  const onReadArticle = postPageNavigationProps?.onReadArticle;
 
   if (!id && !isFallback) {
     return <Custom404 />;
   }
 
+  if (isPostPage && !postPageNavigationProps) {
+    throw new Error('BasePostContent requires navigationProps on post pages');
+  }
+
   return (
     <>
       {isPostPage && (
@@ -50,7 +56,7 @@ export function BasePostContent({
             post={post}
             className="ml-auto"
             contextMenuId="post-page-header-actions"
-            onReadArticle={navigationProps.onReadArticle}
+            onReadArticle={onReadArticle}
             buttonSize={ButtonSize.Small}
           />
         </GoBackHeaderMobile>
diff --git a/packages/shared/src/components/post/PostHeaderActions.tsx b/packages/shared/src/components/post/PostHeaderActions.tsx
index 26b30a7db7f..ec148a732c5 100644
--- a/packages/shared/src/components/post/PostHeaderActions.tsx
+++ b/packages/shared/src/components/post/PostHeaderActions.tsx
@@ -60,14 +60,14 @@ export function PostHeaderActions({
             href={post.sharedPost?.permalink ?? post.permalink}
             target={openNewTab ? '_blank' : '_self'}
             icon={getReadPostButtonIcon(post)}
-            {...(isTwitter && {
-              iconPosition: ButtonIconPosition.Right,
-            })}
+            iconPosition={
+              isTwitter ? ButtonIconPosition.Right : (undefined as never)
+            }
             onClick={onReadArticle}
             data-testid="postActionsRead"
             size={buttonSize}
           >
-            {!inlineActions ? readButtonText : null}
+            {!inlineActions ? readButtonText : undefined}
           </Button>
         </Tooltip>
       )}
diff --git a/packages/shared/src/components/post/PostLoadingSkeleton.tsx b/packages/shared/src/components/post/PostLoadingSkeleton.tsx
index 1f9e2a8b498..1a1a32c783f 100644
--- a/packages/shared/src/components/post/PostLoadingSkeleton.tsx
+++ b/packages/shared/src/components/post/PostLoadingSkeleton.tsx
@@ -15,7 +15,7 @@ function PostLoadingSkeleton({
   type,
   className,
   hasNavigation,
-}: PostLoadingSkeletonProps): ReactElement {
+}: PostLoadingSkeletonProps): ReactElement | null {
   if (!type) {
     return null;
   }
diff --git a/packages/shared/src/components/post/PostUpvotesCommentsCount.tsx b/packages/shared/src/components/post/PostUpvotesCommentsCount.tsx
index b28ddce0cc8..672a676d6c6 100644
--- a/packages/shared/src/components/post/PostUpvotesCommentsCount.tsx
+++ b/packages/shared/src/components/post/PostUpvotesCommentsCount.tsx
@@ -61,7 +61,7 @@ export function PostUpvotesCommentsCount({
         </span>
       )}
       {upvotes > 0 && (
-        <ClickableText onClick={() => onUpvotesClick(upvotes)}>
+        <ClickableText onClick={() => onUpvotesClick?.(upvotes)}>
           {largeNumberFormat(upvotes)} Upvote{upvotes > 1 ? 's' : ''}
         </ClickableText>
       )}
diff --git a/packages/shared/src/components/post/RelatedPostsWidget.tsx b/packages/shared/src/components/post/RelatedPostsWidget.tsx
index 40a7c56dc85..2d4b7c2e573 100644
--- a/packages/shared/src/components/post/RelatedPostsWidget.tsx
+++ b/packages/shared/src/components/post/RelatedPostsWidget.tsx
@@ -24,7 +24,7 @@ export const RelatedPostsWidget = ({
   post,
   perPage = RELATED_POSTS_PER_PAGE_DEFAULT,
   relationType,
-}: RelatedPostsWidgetProps): ReactElement => {
+}: RelatedPostsWidgetProps): ReactElement | null => {
   const {
     relatedPosts,
     isLoading,
diff --git a/packages/shared/src/components/post/analytics/PostShortInfo.tsx b/packages/shared/src/components/post/analytics/PostShortInfo.tsx
index de717de803a..45f8fabde5c 100644
--- a/packages/shared/src/components/post/analytics/PostShortInfo.tsx
+++ b/packages/shared/src/components/post/analytics/PostShortInfo.tsx
@@ -28,7 +28,7 @@ export function PostShortInfo({
   className,
   showImage = true,
   showLinkIcon = true,
-}: PostShortInfoProps): ReactElement {
+}: PostShortInfoProps): ReactElement | null {
   const postLink = useMemo(() => {
     if (!post) {
       return undefined;
diff --git a/packages/shared/src/components/post/brief/BriefPostContent.tsx b/packages/shared/src/components/post/brief/BriefPostContent.tsx
index d1f5b74eb8a..ad37fd2cbff 100644
--- a/packages/shared/src/components/post/brief/BriefPostContent.tsx
+++ b/packages/shared/src/components/post/brief/BriefPostContent.tsx
@@ -458,7 +458,7 @@ const BriefPostContentRaw = ({
                     className={{
                       button: '!max-w-40',
                     }}
-                    hourIndex={digestTimeIndex}
+                    hourIndex={digestTimeIndex ?? 0}
                     setHourIndex={(index) => {
                       onSubscribeDigest({
                         preferredHour: index,
diff --git a/packages/shared/src/components/post/collection/CollectionSubscribeButton.tsx b/packages/shared/src/components/post/collection/CollectionSubscribeButton.tsx
index b6e3aa51d78..184a86b3b88 100644
--- a/packages/shared/src/components/post/collection/CollectionSubscribeButton.tsx
+++ b/packages/shared/src/components/post/collection/CollectionSubscribeButton.tsx
@@ -35,7 +35,7 @@ export const CollectionSubscribeButton = ({
             referenceId: post.id,
           },
         ]
-      : undefined,
+      : [],
   });
   const isSubscribed = !!preferences?.some((item) =>
     checkHasStatusPreference(
diff --git a/packages/shared/src/components/post/common/PostClickbaitShield.tsx b/packages/shared/src/components/post/common/PostClickbaitShield.tsx
index 36bd3c82757..ccfb2504582 100644
--- a/packages/shared/src/components/post/common/PostClickbaitShield.tsx
+++ b/packages/shared/src/components/post/common/PostClickbaitShield.tsx
@@ -83,6 +83,12 @@ export const PostClickbaitShield = ({ post }: { post: Post }): ReactElement => {
                         type: LazyModal.ClickbaitShield,
                       });
                     } else {
+                      if (!user) {
+                        throw new Error(
+                          'PostClickbaitShield requires an authenticated user to edit feed settings',
+                        );
+                      }
+
                       router.push(
                         `${webappUrl}feeds/${user.id}/edit?dview=${FeedSettingsMenu.AI}`,
                       );
diff --git a/packages/shared/src/components/post/smartPrompts/SmartPrompt.tsx b/packages/shared/src/components/post/smartPrompts/SmartPrompt.tsx
index 12ba653e72e..b1df9448a2e 100644
--- a/packages/shared/src/components/post/smartPrompts/SmartPrompt.tsx
+++ b/packages/shared/src/components/post/smartPrompts/SmartPrompt.tsx
@@ -91,7 +91,7 @@ export const SmartPrompt = ({
         <Tab label={PromptDisplay.TLDR}>
           <ShowMoreContent
             className={{ wrapper: 'overflow-hidden' }}
-            content={post.summary}
+            content={post.summary ?? ''}
             charactersLimit={330}
             threshold={50}
           />
diff --git a/packages/shared/src/components/profile/ActivitySection.tsx b/packages/shared/src/components/profile/ActivitySection.tsx
index e9218c210da..b108e8d656c 100644
--- a/packages/shared/src/components/profile/ActivitySection.tsx
+++ b/packages/shared/src/components/profile/ActivitySection.tsx
@@ -53,7 +53,7 @@ export default function ActivitySection<TElement, TError>({
     <ActivityContainer>
       <ActivitySectionTitle>
         {title}
-        {count >= 0 && (
+        {count !== undefined && count >= 0 && (
           <ActivitySectionTitleStat>({count})</ActivitySectionTitleStat>
         )}
       </ActivitySectionTitle>
diff --git a/packages/shared/src/components/profile/ControlledAvatarUpload.tsx b/packages/shared/src/components/profile/ControlledAvatarUpload.tsx
index ade7d9e03fa..99541681820 100644
--- a/packages/shared/src/components/profile/ControlledAvatarUpload.tsx
+++ b/packages/shared/src/components/profile/ControlledAvatarUpload.tsx
@@ -40,7 +40,7 @@ const ControlledAvatarUpload = ({
     >
       <div className="relative size-full overflow-hidden rounded-26">
         <img
-          src={displayImage}
+          src={displayImage ?? undefined}
           alt="Profile avatar"
           className="size-full object-cover"
           data-testid="image_avatar_file"
diff --git a/packages/shared/src/components/profile/ExperienceLevelDropdown.tsx b/packages/shared/src/components/profile/ExperienceLevelDropdown.tsx
index 3ac9871fa74..be5ebe8c0b4 100644
--- a/packages/shared/src/components/profile/ExperienceLevelDropdown.tsx
+++ b/packages/shared/src/components/profile/ExperienceLevelDropdown.tsx
@@ -32,7 +32,7 @@ const ExperienceLevelDropdown = ({
 }: Props): ReactElement => {
   const [open, setOpen] = React.useState(false);
   const [selectedIndex, setSelectedIndex] = React.useState(
-    Object.keys(UserExperienceLevel).indexOf(defaultValue),
+    Object.keys(UserExperienceLevel).indexOf(defaultValue ?? ''),
   );
 
   const {
diff --git a/packages/shared/src/components/profile/ExperienceSettings.tsx b/packages/shared/src/components/profile/ExperienceSettings.tsx
index 11884da5e04..ccf3bfd3cfb 100644
--- a/packages/shared/src/components/profile/ExperienceSettings.tsx
+++ b/packages/shared/src/components/profile/ExperienceSettings.tsx
@@ -17,13 +17,13 @@ export const ExperienceSettings = ({
   experienceType,
   emptyStateMessage,
 }: ExperienceSettingsProps): ReactElement => {
-  const { user } = useAuthContext();
+  const { user, isAuthReady } = useAuthContext();
   const { experiences, isPending } = useUserExperiencesByType(
     experienceType,
-    user?.id,
+    user?.id ?? '',
   );
 
-  if (isPending) {
+  if (!isAuthReady || !user || isPending) {
     return (
       <div className="flex flex-col gap-4">
         <UserExperienceItemSkeleton count={2} />
diff --git a/packages/shared/src/components/profile/JoinedDate.tsx b/packages/shared/src/components/profile/JoinedDate.tsx
index 195d4432fe0..9ab41d62c55 100644
--- a/packages/shared/src/components/profile/JoinedDate.tsx
+++ b/packages/shared/src/components/profile/JoinedDate.tsx
@@ -11,7 +11,7 @@ export default function JoinedDate({
   date,
   dateFormat = 'MMMM y',
   ...props
-}: JoinedDateProps): ReactElement {
+}: JoinedDateProps): ReactElement | null {
   if (!isValid(date)) {
     return null;
   }
diff --git a/packages/shared/src/components/profile/ProfileButton.spec.tsx b/packages/shared/src/components/profile/ProfileButton.spec.tsx
index 9cfa770487e..35571e16823 100644
--- a/packages/shared/src/components/profile/ProfileButton.spec.tsx
+++ b/packages/shared/src/components/profile/ProfileButton.spec.tsx
@@ -38,7 +38,7 @@ const renderComponent = (user = defaultUser): RenderResult => {
         getRedirectUri: jest.fn(),
         closeLogin: jest.fn(),
         trackingId: '21',
-        loginState: null,
+        loginState: undefined,
       }}
     >
       <ProfileButton />
diff --git a/packages/shared/src/components/profile/ProfileButton.tsx b/packages/shared/src/components/profile/ProfileButton.tsx
index cda76d8e2a8..0ba3a8b38b8 100644
--- a/packages/shared/src/components/profile/ProfileButton.tsx
+++ b/packages/shared/src/components/profile/ProfileButton.tsx
@@ -36,7 +36,7 @@ export default function ProfileButton({
   settingsIconOnly,
 }: ProfileButtonProps): ReactElement {
   const { isOpen, onUpdate, wrapHandler } = useInteractivePopup();
-  const { user } = useAuthContext();
+  const { user, isAuthReady } = useAuthContext();
   const { streak, isLoading, isStreaksEnabled } = useReadingStreak();
   const hasCoresAccess = useHasAccessToCores();
   const [animatedCores, setAnimatedCores] = useState<number | null>(null);
@@ -193,6 +193,10 @@ export default function ProfileButton({
     };
   }, [playCounterImpactAnimation, user?.balance?.amount, user?.reputation]);
 
+  if (!isAuthReady || !user) {
+    return <></>;
+  }
+
   return (
     <>
       {settingsIconOnly ? (
diff --git a/packages/shared/src/components/profile/ProfileLink.tsx b/packages/shared/src/components/profile/ProfileLink.tsx
index f06c75cfa75..38bbb0492ff 100644
--- a/packages/shared/src/components/profile/ProfileLink.tsx
+++ b/packages/shared/src/components/profile/ProfileLink.tsx
@@ -13,7 +13,7 @@ function ProfileLinkComponent(
   ref?: Ref<HTMLAnchorElement>,
 ): ReactElement {
   return (
-    <Link href={href} passHref prefetch={false}>
+    <Link href={href ?? ''} passHref prefetch={false}>
       <a
         {...props}
         ref={ref}
diff --git a/packages/shared/src/components/profile/SquadsList.tsx b/packages/shared/src/components/profile/SquadsList.tsx
index 37e1b8afcb6..ac08c0cd5a7 100644
--- a/packages/shared/src/components/profile/SquadsList.tsx
+++ b/packages/shared/src/components/profile/SquadsList.tsx
@@ -191,7 +191,7 @@ export function SquadsList({
       {edges.map(({ node }) => (
         <SquadItem key={node.source.id} membership={node} loading={loading} />
       ))}
-      {isWide && memberships.edges.length > MAX_SQUADS && (
+      {isWide && (memberships?.edges.length ?? 0) > MAX_SQUADS && (
         <Button
           variant={ButtonVariant.Secondary}
           size={ButtonSize.Small}
diff --git a/packages/shared/src/components/profile/UserList.tsx b/packages/shared/src/components/profile/UserList.tsx
index 3a3f7df450c..9ff2a16c25e 100644
--- a/packages/shared/src/components/profile/UserList.tsx
+++ b/packages/shared/src/components/profile/UserList.tsx
@@ -37,7 +37,7 @@ function UserList({
   userInfoProps = {},
 }: UserListProps): ReactElement {
   const loader = (
-    <UserShortInfoPlaceholder placeholderAmount={placeholderAmount} />
+    <UserShortInfoPlaceholder placeholderAmount={placeholderAmount ?? 0} />
   );
 
   if (users?.length) {
diff --git a/packages/shared/src/components/profile/devcard/DevCardFetchWrapper.tsx b/packages/shared/src/components/profile/devcard/DevCardFetchWrapper.tsx
index 181c3ec787d..b9d6747b337 100644
--- a/packages/shared/src/components/profile/devcard/DevCardFetchWrapper.tsx
+++ b/packages/shared/src/components/profile/devcard/DevCardFetchWrapper.tsx
@@ -11,7 +11,7 @@ interface DevCardFetchWrapperProps extends Omit<DevCardProps, 'data'> {
 export function DevCardFetchWrapper({
   userId,
   ...props
-}: DevCardFetchWrapperProps): ReactElement {
+}: DevCardFetchWrapperProps): ReactElement | null {
   const data = useDevCard(userId);
 
   if (!data) {
diff --git a/packages/shared/src/components/profile/devcard/DevCardTwitterCover.tsx b/packages/shared/src/components/profile/devcard/DevCardTwitterCover.tsx
index ae0fb90f1d5..46770f5cd8f 100644
--- a/packages/shared/src/components/profile/devcard/DevCardTwitterCover.tsx
+++ b/packages/shared/src/components/profile/devcard/DevCardTwitterCover.tsx
@@ -10,7 +10,7 @@ import type { UseDevCard } from '../../../hooks/profile/useDevCard';
 export function DevCardTwitterCover({
   devcard,
   coverImage,
-}: Pick<UseDevCard, 'devcard' | 'coverImage'>): ReactElement {
+}: Pick<UseDevCard, 'devcard' | 'coverImage'>): ReactElement | null {
   if (!devcard) {
     return null;
   }
diff --git a/packages/shared/src/components/recruiter/ConnectHeader.tsx b/packages/shared/src/components/recruiter/ConnectHeader.tsx
index 8e414f017d6..930a67ee39c 100644
--- a/packages/shared/src/components/recruiter/ConnectHeader.tsx
+++ b/packages/shared/src/components/recruiter/ConnectHeader.tsx
@@ -16,8 +16,7 @@ import Link from '../utilities/Link';
 import { useOpportunityContext } from '../../features/opportunity/context/OpportunityContext';
 import { boostOpportunityLink, opportunityUrl } from '../../lib/constants';
 import { anchorDefaultRel } from '../../lib/strings';
-import { recruiterPricesQueryOptions } from '../../features/opportunity/queries';
-import { useAuthContext } from '../../contexts/AuthContext';
+import { recruiterPricesPublicQueryOptions } from '../../features/opportunity/queries';
 
 type ItemProps = {
   children: ReactNode;
@@ -50,14 +49,7 @@ export const ConnectHeader = ({
   activeTab,
 }: ConnectHeaderProps = {}): ReactElement => {
   const { opportunity } = useOpportunityContext();
-  const { user, isLoggedIn } = useAuthContext();
-
-  const { data: prices } = useQuery(
-    recruiterPricesQueryOptions({
-      user,
-      isLoggedIn,
-    }),
-  );
+  const { data: prices } = useQuery(recruiterPricesPublicQueryOptions());
 
   const opportunityId = opportunity?.id;
   const forReviewHref = opportunityId
diff --git a/packages/shared/src/components/recruiter/FeedbackList.tsx b/packages/shared/src/components/recruiter/FeedbackList.tsx
index e411aa03891..f4a1cfc371f 100644
--- a/packages/shared/src/components/recruiter/FeedbackList.tsx
+++ b/packages/shared/src/components/recruiter/FeedbackList.tsx
@@ -128,7 +128,8 @@ interface FeedbackCardProps {
 const FeedbackCard = ({ feedback }: FeedbackCardProps): ReactElement => {
   const showSentiment = feedback.sentiment !== FeedbackSentiment.Unspecified;
   const showUrgency = feedback.urgency !== FeedbackUrgency.Unspecified;
-  const hasUserContext = feedback.userContext;
+  const { userContext } = feedback;
+  const hasUserContext = !!userContext;
 
   return (
     <div
@@ -171,8 +172,8 @@ const FeedbackCard = ({ feedback }: FeedbackCardProps): ReactElement => {
       )}
 
       {/* User context - seniority and location */}
-      {hasUserContext && (
-        <UserContextDisplay userContext={feedback.userContext} />
+      {hasUserContext && userContext && (
+        <UserContextDisplay userContext={userContext} />
       )}
     </div>
   );
diff --git a/packages/shared/src/components/recruiter/MatchProfile.tsx b/packages/shared/src/components/recruiter/MatchProfile.tsx
index 81f9e3155fc..03bfeeecb53 100644
--- a/packages/shared/src/components/recruiter/MatchProfile.tsx
+++ b/packages/shared/src/components/recruiter/MatchProfile.tsx
@@ -83,7 +83,7 @@ export const MatchProfile = ({ profile }: MatchProfileProps): ReactElement => {
                 className="text-accent-onion-default"
                 size={IconSize.XSmall}
               />
-              <span>{largeNumberFormat(profile.reputation)}</span>
+              <span>{largeNumberFormat(profile.reputation ?? 0)}</span>
             </FlexRow>
           }
         />
diff --git a/packages/shared/src/components/search/SearchFilterTimeButton.tsx b/packages/shared/src/components/search/SearchFilterTimeButton.tsx
index fb35de29c8e..8591c8cbd3f 100644
--- a/packages/shared/src/components/search/SearchFilterTimeButton.tsx
+++ b/packages/shared/src/components/search/SearchFilterTimeButton.tsx
@@ -23,7 +23,7 @@ const SearchFilterTimeButton = () => {
             size={ButtonSize.Small}
             aria-label="Open time filter menu"
           >
-            {SearchTime[time]}
+            {SearchTime[time as keyof typeof SearchTime]}
           </Button>
         </DropdownMenuTrigger>
         <DropdownMenuContent>
diff --git a/packages/shared/src/components/search/SearchPanel/SearchPanelContext.ts b/packages/shared/src/components/search/SearchPanel/SearchPanelContext.ts
index fc36494d360..44f22f87e0c 100644
--- a/packages/shared/src/components/search/SearchPanel/SearchPanelContext.ts
+++ b/packages/shared/src/components/search/SearchPanel/SearchPanelContext.ts
@@ -3,7 +3,7 @@ import { createContext } from 'react';
 import { SearchProviderEnum } from '../../../graphql/search';
 
 export type SearchPanelContextValue = {
-  provider: SearchProviderEnum;
+  provider?: SearchProviderEnum;
   providerText?: string;
   providerIcon?: ReactElement;
   query: string;
@@ -13,7 +13,7 @@ export type SearchPanelContextValue = {
     text,
     icon,
   }: {
-    provider: SearchProviderEnum;
+    provider?: SearchProviderEnum;
     text?: string;
     icon?: ReactElement;
   }) => void;
diff --git a/packages/shared/src/components/search/SearchPanel/SearchPanelDropdown.tsx b/packages/shared/src/components/search/SearchPanel/SearchPanelDropdown.tsx
index cbe9109ca7b..e834f84522a 100644
--- a/packages/shared/src/components/search/SearchPanel/SearchPanelDropdown.tsx
+++ b/packages/shared/src/components/search/SearchPanel/SearchPanelDropdown.tsx
@@ -59,7 +59,11 @@ const SearchPanelDropdown = ({ query = '', anchor }: Props): ReactElement => {
 
     event.preventDefault();
 
-    const indexModifier = keyToIndexModifier[pressedKey];
+    const indexModifier = keyToIndexModifier[pressedKey as ArrowKeyEnum];
+
+    if (indexModifier === undefined) {
+      return;
+    }
 
     const nextElement = navigableElements[activeElementIndex + indexModifier];
 
diff --git a/packages/shared/src/components/search/SearchPanel/SearchPanelInputCursor.tsx b/packages/shared/src/components/search/SearchPanel/SearchPanelInputCursor.tsx
index e1657eb6eca..e763f52909d 100644
--- a/packages/shared/src/components/search/SearchPanel/SearchPanelInputCursor.tsx
+++ b/packages/shared/src/components/search/SearchPanel/SearchPanelInputCursor.tsx
@@ -13,7 +13,7 @@ export type SearchPanelInputCursorProps = {
 
 export const SearchPanelInputCursor = ({
   className,
-}: SearchPanelInputCursorProps): ReactElement => {
+}: SearchPanelInputCursorProps): ReactElement | null => {
   const searchPanel = useContext(SearchPanelContext);
   const purify = useDomPurify();
 
diff --git a/packages/shared/src/components/search/SearchPanel/SearchPanelPostSuggestions.tsx b/packages/shared/src/components/search/SearchPanel/SearchPanelPostSuggestions.tsx
index fd8710f9668..c66801e77f7 100644
--- a/packages/shared/src/components/search/SearchPanel/SearchPanelPostSuggestions.tsx
+++ b/packages/shared/src/components/search/SearchPanel/SearchPanelPostSuggestions.tsx
@@ -54,7 +54,7 @@ const PanelItem = ({
 export const SearchPanelPostSuggestions = ({
   className,
   title,
-}: SearchPanelPostSuggestionsProps): ReactElement => {
+}: SearchPanelPostSuggestionsProps): ReactElement | null => {
   const router = useRouter();
   const { logEvent } = useLogContext();
   const searchPanel = useContext(SearchPanelContext);
diff --git a/packages/shared/src/components/search/SearchPanel/SearchPanelProvider.tsx b/packages/shared/src/components/search/SearchPanel/SearchPanelProvider.tsx
index f98d950b0e9..bc4770a3209 100644
--- a/packages/shared/src/components/search/SearchPanel/SearchPanelProvider.tsx
+++ b/packages/shared/src/components/search/SearchPanel/SearchPanelProvider.tsx
@@ -21,13 +21,17 @@ const providerToComponentMap: Record<
 
 export const SearchPanelProvider = ({
   className,
-}: SearchPanelProviderProps): ReactElement => {
+}: SearchPanelProviderProps): ReactElement | null => {
   const searchPanel = useContext(SearchPanelContext);
 
   if (searchPanel.providerIcon) {
     return searchPanel.providerIcon;
   }
 
+  if (!searchPanel.provider) {
+    return null;
+  }
+
   const Component = providerToComponentMap[searchPanel.provider];
 
   if (!Component) {
diff --git a/packages/shared/src/components/search/SearchResults/SearchResultsTags.tsx b/packages/shared/src/components/search/SearchResults/SearchResultsTags.tsx
index eb75d2e3aa6..fe6fdf6e1b6 100644
--- a/packages/shared/src/components/search/SearchResults/SearchResultsTags.tsx
+++ b/packages/shared/src/components/search/SearchResults/SearchResultsTags.tsx
@@ -13,7 +13,7 @@ interface SearchResultsTagsProps {
 
 export const SearchResultsTags = (
   props: SearchResultsTagsProps,
-): ReactElement => {
+): ReactElement | null => {
   const { items = [], isLoading, onTagClick } = props;
 
   if (!isLoading && !items.length) {
diff --git a/packages/shared/src/components/sidebar/ClickableNavItem.tsx b/packages/shared/src/components/sidebar/ClickableNavItem.tsx
index bb8bc8a911e..c60dd39fe98 100644
--- a/packages/shared/src/components/sidebar/ClickableNavItem.tsx
+++ b/packages/shared/src/components/sidebar/ClickableNavItem.tsx
@@ -34,8 +34,14 @@ export function ClickableNavItem({
   );
 
   if (!isButton && (!item.action || item.path)) {
+    const itemPath = item.path;
+
+    if (!itemPath) {
+      throw new Error('ClickableNavItem link items require a path');
+    }
+
     return (
-      <Link href={item.path} passHref prefetch={false}>
+      <Link href={itemPath} passHref prefetch={false}>
         <a
           {...props}
           {...combinedClicks(onClick)}
diff --git a/packages/shared/src/components/sidebar/Sidebar.tsx b/packages/shared/src/components/sidebar/Sidebar.tsx
index 7433b7d0879..347ed949036 100644
--- a/packages/shared/src/components/sidebar/Sidebar.tsx
+++ b/packages/shared/src/components/sidebar/Sidebar.tsx
@@ -28,7 +28,7 @@ export const Sidebar = ({
   onNavTabClick,
   onLogoClick,
   activePage,
-}: SidebarProps): ReactElement => {
+}: SidebarProps): ReactElement | null => {
   const isLaptop = useViewSize(ViewSize.Laptop);
   const isTablet = useViewSize(ViewSize.Tablet);
   const featureTheme = useFeatureTheme();
diff --git a/packages/shared/src/components/sidebar/SidebarItem.spec.tsx b/packages/shared/src/components/sidebar/SidebarItem.spec.tsx
index ab4f08fcb01..45eb5199f63 100644
--- a/packages/shared/src/components/sidebar/SidebarItem.spec.tsx
+++ b/packages/shared/src/components/sidebar/SidebarItem.spec.tsx
@@ -17,7 +17,7 @@ const renderComponent = (shouldShowLabel: boolean) =>
   render(
     <AuthContext.Provider
       value={{
-        user: null,
+        user: undefined,
         isAuthReady: true,
         isFetched: true,
         isLoggedIn: false,
diff --git a/packages/shared/src/components/sidebar/SidebarItem.tsx b/packages/shared/src/components/sidebar/SidebarItem.tsx
index 914a579718d..c894127b394 100644
--- a/packages/shared/src/components/sidebar/SidebarItem.tsx
+++ b/packages/shared/src/components/sidebar/SidebarItem.tsx
@@ -44,7 +44,7 @@ export const SidebarItem = ({
         showLogin={
           item.requiresLogin && !user
             ? () => showLogin({ trigger: item.title as AuthTriggersType })
-            : null
+            : undefined
         }
         isButton={isItemsButton && !item?.isForcedLink}
       >
diff --git a/packages/shared/src/components/sidebar/SidebarList.tsx b/packages/shared/src/components/sidebar/SidebarList.tsx
index 8e5e3ababe8..7fff7d0ee80 100644
--- a/packages/shared/src/components/sidebar/SidebarList.tsx
+++ b/packages/shared/src/components/sidebar/SidebarList.tsx
@@ -56,7 +56,7 @@ function SidebarList({
           size={ButtonSize.Small}
           className="flex -rotate-90 tablet:hidden"
           icon={<ArrowIcon />}
-          onClick={onRequestClose}
+          onClick={onRequestClose ?? undefined}
         />
         <span className="ml-2 font-bold typo-title3">{title}</span>
       </span>
diff --git a/packages/shared/src/components/sidebar/common.tsx b/packages/shared/src/components/sidebar/common.tsx
index b24bfadef6a..b6a1619254c 100644
--- a/packages/shared/src/components/sidebar/common.tsx
+++ b/packages/shared/src/components/sidebar/common.tsx
@@ -33,7 +33,7 @@ export interface SidebarMenuItem {
 }
 
 interface ListIconProps {
-  Icon: React.ComponentType<{ className }>;
+  Icon: React.ComponentType<{ className?: string }>;
 }
 
 export interface ItemInnerProps {
diff --git a/packages/shared/src/components/sidebar/sections/BookmarkSection.tsx b/packages/shared/src/components/sidebar/sections/BookmarkSection.tsx
index 9cf1cc10bd6..b747aea9c0b 100644
--- a/packages/shared/src/components/sidebar/sections/BookmarkSection.tsx
+++ b/packages/shared/src/components/sidebar/sections/BookmarkSection.tsx
@@ -29,7 +29,9 @@ export const BookmarkSection = ({
   const { createFolder } = useCreateBookmarkFolder();
 
   const isLaptop = useViewSize(ViewSize.Laptop);
-  const rightIcon = !isLaptop && (() => <ArrowIcon className="rotate-90" />);
+  const rightIcon = !isLaptop
+    ? () => <ArrowIcon className="rotate-90" />
+    : undefined;
 
   const handleAddFolder = useCallback(() => {
     openModal({
@@ -43,7 +45,7 @@ export const BookmarkSection = ({
     });
   }, [openModal, closeModal, createFolder]);
 
-  const menuItems: SidebarMenuItem[] = [
+  const allMenuItems = [
     briefUIFeatureValue && {
       icon: (active: boolean) => (
         <ListIcon Icon={() => <BriefIcon secondary={active} />} />
@@ -86,7 +88,10 @@ export const BookmarkSection = ({
       requiresLogin: true,
       rightIcon,
     })),
-  ].filter(Boolean);
+  ];
+  const menuItems: SidebarMenuItem[] = allMenuItems.filter(
+    Boolean,
+  ) as SidebarMenuItem[];
 
   return (
     <Section
diff --git a/packages/shared/src/components/sidebar/sections/NetworkSection.tsx b/packages/shared/src/components/sidebar/sections/NetworkSection.tsx
index ca3c246b2e0..0762ae8be2e 100644
--- a/packages/shared/src/components/sidebar/sections/NetworkSection.tsx
+++ b/packages/shared/src/components/sidebar/sections/NetworkSection.tsx
@@ -69,7 +69,7 @@ export const NetworkSection = ({
         isForcedLink: true,
       },
       ...squadItems,
-    ].filter(Boolean);
+    ].filter(Boolean) as SidebarMenuItem[];
   }, [squads, isModeratorInAnySquad, count]);
 
   return (
diff --git a/packages/shared/src/components/squads/SquadCommentJoinBanner.tsx b/packages/shared/src/components/squads/SquadCommentJoinBanner.tsx
index a3a457af28e..c84b362525d 100644
--- a/packages/shared/src/components/squads/SquadCommentJoinBanner.tsx
+++ b/packages/shared/src/components/squads/SquadCommentJoinBanner.tsx
@@ -32,7 +32,7 @@ export const SquadCommentJoinBanner = ({
   squad,
   logOrigin,
   post,
-}: SquadCommentJoinBannerProps): ReactElement => {
+}: SquadCommentJoinBannerProps): ReactElement | null => {
   const queryClient = useQueryClient();
   const [isSquadMember, setIsSquadMember] = useState(!!squad?.currentMember);
   const isMobile = useViewSize(ViewSize.MobileL);
diff --git a/packages/shared/src/components/squads/SquadPostListItem.tsx b/packages/shared/src/components/squads/SquadPostListItem.tsx
index e8f36bf3bdf..db392689898 100644
--- a/packages/shared/src/components/squads/SquadPostListItem.tsx
+++ b/packages/shared/src/components/squads/SquadPostListItem.tsx
@@ -46,7 +46,7 @@ export const SquadPostListItem = ({
           />
         )}
         <p className="mr-6 mt-1 line-clamp-3 text-text-primary typo-callout">
-          {post.title ?? post.sharedPost.title}
+          {post.title ?? post.sharedPost?.title}
         </p>
       </div>
     </article>
diff --git a/packages/shared/src/components/squads/SquadTabs.tsx b/packages/shared/src/components/squads/SquadTabs.tsx
index 1cc1b7f2437..ca8c74544d6 100644
--- a/packages/shared/src/components/squads/SquadTabs.tsx
+++ b/packages/shared/src/components/squads/SquadTabs.tsx
@@ -24,7 +24,9 @@ export function SquadTabs({ active, handle }: SquadTabsProps): ReactElement {
   const { count } = useSquadPendingPosts({
     squadId: squad?.id,
   });
-  const isModerator = verifyPermission(squad, SourcePermissions.ModeratePost);
+  const isModerator = squad
+    ? verifyPermission(squad, SourcePermissions.ModeratePost)
+    : false;
   const squadLink = `${webappUrl}squads/${handle}`;
   const pendingTabLabel = count
     ? `${SquadTab.PendingPosts} (${count})`
diff --git a/packages/shared/src/components/squads/layout/SquadDirectoryNavbarItem.tsx b/packages/shared/src/components/squads/layout/SquadDirectoryNavbarItem.tsx
index 65b5d81a0f4..6d2b2ae87f5 100644
--- a/packages/shared/src/components/squads/layout/SquadDirectoryNavbarItem.tsx
+++ b/packages/shared/src/components/squads/layout/SquadDirectoryNavbarItem.tsx
@@ -2,7 +2,6 @@ import classNames from 'classnames';
 import type { ComponentProps, ReactElement } from 'react';
 import React from 'react';
 import Link from '../../utilities/Link';
-import ConditionalWrapper from '../../ConditionalWrapper';
 import type { ButtonProps, ButtonSize } from '../../buttons/Button';
 import { Button, ButtonVariant } from '../../buttons/Button';
 
@@ -23,6 +22,22 @@ export function SquadDirectoryNavbarItem({
   onClick,
   elementProps = {},
 }: SquadNavbarItemProps): ReactElement {
+  const button = (
+    <Button
+      aria-current={isActive ? 'page' : undefined}
+      aria-label={`Navigate to ${label}'s directory page`}
+      className="capitalize"
+      href={path}
+      onClick={onClick}
+      size={buttonSize}
+      tag={path ? 'a' : 'button'}
+      pressed={isActive}
+      variant={isActive ? ButtonVariant.Float : ButtonVariant.Tertiary}
+    >
+      {label}
+    </Button>
+  );
+
   return (
     <li
       {...elementProps}
@@ -33,29 +48,14 @@ export function SquadDirectoryNavbarItem({
         elementProps?.className,
       )}
     >
-      <ConditionalWrapper
-        condition={!!path}
-        wrapper={(component) => (
-          // TODO: WT-2239 - Remove legacyBehavior prop once all SquadDirectoryNavbarItem components are updated
-          <Link href={path} legacyBehavior>
-            {component}
-          </Link>
-        )}
-      >
-        <Button
-          aria-current={isActive ? 'page' : undefined}
-          aria-label={`Navigate to ${label}'s directory page`}
-          className="capitalize"
-          href={path}
-          onClick={onClick}
-          size={buttonSize}
-          tag={path ? 'a' : 'button'}
-          pressed={isActive}
-          variant={isActive ? ButtonVariant.Float : ButtonVariant.Tertiary}
-        >
-          {label}
-        </Button>
-      </ConditionalWrapper>
+      {path ? (
+        // TODO: WT-2239 - Remove legacyBehavior prop once all SquadDirectoryNavbarItem components are updated
+        <Link href={path} legacyBehavior>
+          {button}
+        </Link>
+      ) : (
+        button
+      )}
     </li>
   );
 }
diff --git a/packages/shared/src/components/squads/layout/useSquadDirectoryLayout.ts b/packages/shared/src/components/squads/layout/useSquadDirectoryLayout.ts
index 43b7c2f10f1..7dcd2e383de 100644
--- a/packages/shared/src/components/squads/layout/useSquadDirectoryLayout.ts
+++ b/packages/shared/src/components/squads/layout/useSquadDirectoryLayout.ts
@@ -19,7 +19,7 @@ export const useSquadDirectoryLayout = (): SquadDirectoryLayoutReturn => {
   const { data: categories, isFetched } = useSquadCategories();
 
   const tabs = useMemo(() => {
-    const path = { ...squadCategoriesPaths };
+    const path: Partial<Record<string, string>> = { ...squadCategoriesPaths };
 
     if (!isFetched) {
       return {};
@@ -44,7 +44,7 @@ export const useSquadDirectoryLayout = (): SquadDirectoryLayoutReturn => {
   return {
     hasSquad,
     squads,
-    categoryPaths: tabs,
+    categoryPaths: tabs as Record<string, string>,
     isMobileLayout: !isLaptop,
   };
 };
diff --git a/packages/shared/src/components/squads/stack/SourceStackModal.tsx b/packages/shared/src/components/squads/stack/SourceStackModal.tsx
index 9858a086df5..e3955baffd2 100644
--- a/packages/shared/src/components/squads/stack/SourceStackModal.tsx
+++ b/packages/shared/src/components/squads/stack/SourceStackModal.tsx
@@ -3,7 +3,10 @@ import React, { useMemo, useState } from 'react';
 import { FormProvider, useForm } from 'react-hook-form';
 import { z } from 'zod';
 import { zodResolver } from '@hookform/resolvers/zod';
-import type { ModalProps } from '../../modals/common/Modal';
+import type {
+  LazyModalCommonProps,
+  ModalProps,
+} from '../../modals/common/Modal';
 import { Modal } from '../../modals/common/Modal';
 import { TextField } from '../../fields/TextField';
 import { Button, ButtonVariant } from '../../buttons/Button';
@@ -23,7 +26,8 @@ const sourceStackFormSchema = z.object({
 
 type SourceStackFormData = z.infer<typeof sourceStackFormSchema>;
 
-type SourceStackModalProps = Omit<ModalProps, 'children'> & {
+type SourceStackModalProps = Omit<ModalProps, 'children' | 'onRequestClose'> & {
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
   onSubmit: (input: AddSourceStackInput) => Promise<void>;
   existingItem?: SourceStack;
 };
@@ -67,7 +71,7 @@ export function SourceStackModal({
     await onSubmit({
       title: data.title.trim(),
     });
-    rest.onRequestClose?.(null);
+    rest.onRequestClose?.(undefined);
   });
 
   const filteredSuggestions = useMemo(() => {
diff --git a/packages/shared/src/components/squads/utils.tsx b/packages/shared/src/components/squads/utils.tsx
index da2f560756f..ad64953d98d 100644
--- a/packages/shared/src/components/squads/utils.tsx
+++ b/packages/shared/src/components/squads/utils.tsx
@@ -60,7 +60,7 @@ export const createModerationPromptProps: PromptOptions = {
     title: 'Got it',
     className: 'tablet:w-full',
   },
-  cancelButton: null,
+  cancelButton: undefined,
   promptSize: ModalSize.XSmall,
   icon: <TimerIcon size={IconSize.XXXLarge} />,
 };
diff --git a/packages/shared/src/components/streak/popup/DayStreak.tsx b/packages/shared/src/components/streak/popup/DayStreak.tsx
index d32030bb909..fbfb4a341fd 100644
--- a/packages/shared/src/components/streak/popup/DayStreak.tsx
+++ b/packages/shared/src/components/streak/popup/DayStreak.tsx
@@ -87,7 +87,7 @@ export function DayStreak({
           />
         )}
         {renderIcon()}
-        {dateFormatInTimezone(date, 'iiiii', user.timezone)}
+        {dateFormatInTimezone(date, 'iiiii', user?.timezone ?? 'UTC')}
       </div>
     </Tooltip>
   );
diff --git a/packages/shared/src/components/tags/TagElement.tsx b/packages/shared/src/components/tags/TagElement.tsx
index 8686daa653e..a7086ca6d57 100644
--- a/packages/shared/src/components/tags/TagElement.tsx
+++ b/packages/shared/src/components/tags/TagElement.tsx
@@ -21,21 +21,10 @@ export const TagElement = ({
   isHighlighted = false,
   ...attrs
 }: OnboardingTagProps): ReactElement => {
-  return (
-    <Button
-      className={classNames(
-        {
-          'btn-tag': !isSelected,
-        },
-        'relative',
-      )}
-      variant={isSelected ? ButtonVariant.Primary : ButtonVariant.Float}
-      color={isSelected ? ButtonColor.Cabbage : undefined}
-      onClick={() => {
-        onClick({ tag });
-      }}
-      {...attrs}
-    >
+  const className = classNames({ 'btn-tag': !isSelected }, 'relative');
+  const handleClick = () => onClick({ tag });
+  const content = (
+    <>
       {tag.name}
       {isHighlighted && (
         <AlertDot
@@ -43,6 +32,31 @@ export const TagElement = ({
           color={AlertColor.Cabbage}
         />
       )}
+    </>
+  );
+
+  if (isSelected) {
+    return (
+      <Button
+        className={className}
+        variant={ButtonVariant.Primary}
+        color={ButtonColor.Cabbage}
+        onClick={handleClick}
+        {...attrs}
+      >
+        {content}
+      </Button>
+    );
+  }
+
+  return (
+    <Button
+      className={className}
+      variant={ButtonVariant.Float}
+      onClick={handleClick}
+      {...attrs}
+    >
+      {content}
     </Button>
   );
 };
diff --git a/packages/shared/src/components/tooltip/Tooltip.tsx b/packages/shared/src/components/tooltip/Tooltip.tsx
index a9ec11d6a02..d044dee8062 100644
--- a/packages/shared/src/components/tooltip/Tooltip.tsx
+++ b/packages/shared/src/components/tooltip/Tooltip.tsx
@@ -47,9 +47,11 @@ export function Tooltip({
         onOpenChange={setOpen}
       >
         <RadixPrimitive.Trigger
-          aria-label={showAriaLabel && content.toString()}
+          aria-label={showAriaLabel ? content.toString() : undefined}
           asChild
-          onMouseUp={(e) => e.currentTarget.blur()}
+          onMouseUp={(e: React.MouseEvent) =>
+            (e.currentTarget as HTMLElement).blur()
+          }
           {...(enableMobileClick && { onClick: () => setOpen(true) })}
         >
           {children}
diff --git a/packages/shared/src/components/typography/Typography.tsx b/packages/shared/src/components/typography/Typography.tsx
index 259c7f7d867..28d8c5dbe39 100644
--- a/packages/shared/src/components/typography/Typography.tsx
+++ b/packages/shared/src/components/typography/Typography.tsx
@@ -94,7 +94,7 @@ function BaseTypography<TagName extends AllowedTags>(
     className,
     type,
     { 'font-bold': bold, 'text-center': center },
-    color ?? tagToColor[tag],
+    color ?? (tagToColor as Record<string, TypographyColor | undefined>)[tag],
     truncate && truncateTextClassNames,
   );
   const Tag = classed(tag, classes);
diff --git a/packages/shared/src/components/widgets/Alert.tsx b/packages/shared/src/components/widgets/Alert.tsx
index f2988cc2055..73cdd492c15 100644
--- a/packages/shared/src/components/widgets/Alert.tsx
+++ b/packages/shared/src/components/widgets/Alert.tsx
@@ -68,8 +68,8 @@ function Alert({
         <span
           className={classNames(
             'flex flex-1 typo-callout',
-            children && 'font-bold',
-            children && fontColor[type],
+            !!children && 'font-bold',
+            !!children && fontColor[type],
           )}
         >
           {title}
diff --git a/packages/shared/src/components/widgets/SocialShareList.tsx b/packages/shared/src/components/widgets/SocialShareList.tsx
index ff1d1a8a55c..61761d6626f 100644
--- a/packages/shared/src/components/widgets/SocialShareList.tsx
+++ b/packages/shared/src/components/widgets/SocialShareList.tsx
@@ -114,7 +114,7 @@ export function SocialShareList({
         onClick={() => openShareLink(ShareProvider.Email)}
         label="Email"
       />
-      {globalThis?.navigator?.share && (
+      {typeof globalThis?.navigator?.share === 'function' && (
         <SocialShareButton
           icon={<MenuIcon size={IconSize.Large} className="rotate-90" />}
           variant={ButtonVariant.Primary}
diff --git a/packages/shared/src/components/withFeaturesBoundary.spec.tsx b/packages/shared/src/components/withFeaturesBoundary.spec.tsx
index 1ad7d2de24f..2365511b69e 100644
--- a/packages/shared/src/components/withFeaturesBoundary.spec.tsx
+++ b/packages/shared/src/components/withFeaturesBoundary.spec.tsx
@@ -1,13 +1,16 @@
 import React from 'react';
 import { render, screen } from '@testing-library/react';
 import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
+import type { FeaturesReadyContextValue } from './GrowthBookProvider';
 import { FeaturesReadyContext } from './GrowthBookProvider';
 import { withFeaturesBoundary } from './withFeaturesBoundary';
 
 const renderComponent = (Component: React.ElementType, ready = true) => {
   return render(
     <QueryClientProvider client={new QueryClient()}>
-      <FeaturesReadyContext.Provider value={{ ready }}>
+      <FeaturesReadyContext.Provider
+        value={{ ready } as FeaturesReadyContextValue}
+      >
         <Component />
       </FeaturesReadyContext.Provider>
       ,
diff --git a/packages/shared/src/contexts/BuyCoresContext/types.ts b/packages/shared/src/contexts/BuyCoresContext/types.ts
index 1fdbf02b8c6..f07c75aef66 100644
--- a/packages/shared/src/contexts/BuyCoresContext/types.ts
+++ b/packages/shared/src/contexts/BuyCoresContext/types.ts
@@ -4,7 +4,9 @@ import { createContext, useContext } from 'react';
 import type { OpenCheckoutFn } from '../payment/context';
 import type { Origin } from '../../lib/log';
 
-export const BuyCoresContext = createContext<BuyCoresContextData>(undefined);
+export const BuyCoresContext = createContext<BuyCoresContextData>(
+  undefined as unknown as BuyCoresContextData,
+);
 
 export const useBuyCoresContext = (): BuyCoresContextData =>
   useContext(BuyCoresContext);
diff --git a/packages/shared/src/contexts/NotificationsContext.tsx b/packages/shared/src/contexts/NotificationsContext.tsx
index 8edeac3958d..a7f6885c0bd 100644
--- a/packages/shared/src/contexts/NotificationsContext.tsx
+++ b/packages/shared/src/contexts/NotificationsContext.tsx
@@ -8,8 +8,9 @@ export interface NotificationsContextData {
   incrementUnreadCount: () => void;
 }
 
-const NotificationsContext =
-  React.createContext<NotificationsContextData>(null);
+const NotificationsContext = React.createContext<NotificationsContextData>(
+  null as unknown as NotificationsContextData,
+);
 
 export default NotificationsContext;
 
diff --git a/packages/shared/src/contexts/PostReferrerContext.tsx b/packages/shared/src/contexts/PostReferrerContext.tsx
index 29651ccd42d..640a678849d 100644
--- a/packages/shared/src/contexts/PostReferrerContext.tsx
+++ b/packages/shared/src/contexts/PostReferrerContext.tsx
@@ -9,7 +9,7 @@ import { usePrevious } from '../hooks';
 
 type ReferredPost = {
   id: Post['id'];
-  author?: Pick<Post['author'], 'id'>;
+  author?: Pick<NonNullable<Post['author']>, 'id'>;
   origin?: Origin;
 };
 
diff --git a/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentContext.tsx b/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentContext.tsx
index dc292dca9b4..ca94220be01 100644
--- a/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentContext.tsx
+++ b/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentContext.tsx
@@ -2,11 +2,25 @@ import type { ReactElement } from 'react';
 import React from 'react';
 import type { RecruiterContextProviderProps } from './types';
 import { RecruiterPaymentPaddleContextProvider } from './RecruiterPaymentPaddleContext';
+import { RecruiterPaymentPublicContextProvider } from './RecruiterPaymentPublicContext';
+import { useAuthContext } from '../AuthContext';
 
 export const RecruiterPaymentContext = ({
   children,
   ...props
 }: RecruiterContextProviderProps): ReactElement => {
+  const { user, isLoggedIn } = useAuthContext();
+
+  if (!user || !isLoggedIn) {
+    return (
+      <RecruiterPaymentPublicContextProvider
+        onPaymentComplete={props.onCompletion}
+      >
+        {children}
+      </RecruiterPaymentPublicContextProvider>
+    );
+  }
+
   return (
     <RecruiterPaymentPaddleContextProvider {...props}>
       {children}
diff --git a/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentPaddleContext.tsx b/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentPaddleContext.tsx
index 3f26ac0c061..bde9bfa9cb6 100644
--- a/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentPaddleContext.tsx
+++ b/packages/shared/src/contexts/RecruiterPaymentContext/RecruiterPaymentPaddleContext.tsx
@@ -22,6 +22,13 @@ export const RecruiterPaymentPaddleContextProvider = ({
   const router = useRouter();
   const { user, isLoggedIn } = useAuthContext();
   const { logEvent } = useLogContext();
+
+  if (!user) {
+    throw new Error(
+      'RecruiterPaymentPaddleContextProvider requires an authenticated user',
+    );
+  }
+
   const [selectedProduct, setSelectedProduct] =
     useState<RecruiterProductOption>();
   const logRef = useRef<typeof logEvent>();
diff --git a/packages/shared/src/contexts/RecruiterPaymentContext/types.ts b/packages/shared/src/contexts/RecruiterPaymentContext/types.ts
index a37f6d8f827..cbaab8861f4 100644
--- a/packages/shared/src/contexts/RecruiterPaymentContext/types.ts
+++ b/packages/shared/src/contexts/RecruiterPaymentContext/types.ts
@@ -6,7 +6,9 @@ import type { Origin } from '../../lib/log';
 import type { ProductPricingPreview } from '../../graphql/paddle';
 
 export const RecruiterPaymentContext =
-  createContext<RecruiterPaymentContextData>(undefined);
+  createContext<RecruiterPaymentContextData>(
+    undefined as unknown as RecruiterPaymentContextData,
+  );
 
 export const useRecruiterPaymentContext = (): RecruiterPaymentContextData =>
   useContext(RecruiterPaymentContext);
diff --git a/packages/shared/src/contexts/WriteCommentContext.ts b/packages/shared/src/contexts/WriteCommentContext.ts
index 796ceac6ba6..c68cc88fb0c 100644
--- a/packages/shared/src/contexts/WriteCommentContext.ts
+++ b/packages/shared/src/contexts/WriteCommentContext.ts
@@ -6,7 +6,7 @@ interface WriteCommentContextProp {
 }
 
 export const WriteCommentContext = createContext<WriteCommentContextProp>({
-  mutateComment: null,
+  mutateComment: null as unknown as UseMutateCommentResult,
 });
 
 export const useWriteCommentContext = (): WriteCommentContextProp =>
diff --git a/packages/shared/src/contexts/payment/context.ts b/packages/shared/src/contexts/payment/context.ts
index ffa13aeac25..1cfc7f90e62 100644
--- a/packages/shared/src/contexts/payment/context.ts
+++ b/packages/shared/src/contexts/payment/context.ts
@@ -29,7 +29,9 @@ export interface PaymentContextData {
   setPriceType?: Dispatch<SetStateAction<PurchaseType>>;
 }
 
-export const PaymentContext = createContext<PaymentContextData>(undefined);
+export const PaymentContext = createContext<PaymentContextData>(
+  undefined as unknown as PaymentContextData,
+);
 
 export const usePaymentContext = (): PaymentContextData => {
   const context = useContext(PaymentContext);
diff --git a/packages/shared/src/contexts/payment/index.tsx b/packages/shared/src/contexts/payment/index.tsx
index 2fde6aeaccc..44b4fffa28b 100644
--- a/packages/shared/src/contexts/payment/index.tsx
+++ b/packages/shared/src/contexts/payment/index.tsx
@@ -10,7 +10,10 @@ import type { StoreKitSubProviderProps } from './StoreKit';
 import { iOSSupportsPlusPurchase } from '../../lib/ios';
 
 const StoreKitSubProvider = dynamic(() =>
-  import('./StoreKit').then((mod) => mod.StoreKitSubProvider),
+  import('./StoreKit').then(
+    (mod) =>
+      mod.StoreKitSubProvider as React.ComponentType<StoreKitSubProviderProps>,
+  ),
 );
 
 export const PaymentContextProvider = ({
@@ -26,9 +29,7 @@ export const PaymentContextProvider = ({
   }
 
   if (checkIsExtension()) {
-    return (
-      <ChromeExtensionProvider {...props}>{children}</ChromeExtensionProvider>
-    );
+    return <ChromeExtensionProvider>{children}</ChromeExtensionProvider>;
   }
 
   return (
diff --git a/packages/shared/src/features/boost/CampaignList.tsx b/packages/shared/src/features/boost/CampaignList.tsx
index e89051f3484..dad2a609944 100644
--- a/packages/shared/src/features/boost/CampaignList.tsx
+++ b/packages/shared/src/features/boost/CampaignList.tsx
@@ -65,7 +65,7 @@ export function CampaignList({
         <CampaignListItem
           key={campaign.id}
           campaign={campaign}
-          onClick={() => onClick(campaign)}
+          onClick={() => onClick?.(campaign)}
           className="px-6 py-2"
         />
       ))}
diff --git a/packages/shared/src/features/boost/usePostBoostEstimation.ts b/packages/shared/src/features/boost/usePostBoostEstimation.ts
index dbae96eb330..30fff188640 100644
--- a/packages/shared/src/features/boost/usePostBoostEstimation.ts
+++ b/packages/shared/src/features/boost/usePostBoostEstimation.ts
@@ -17,9 +17,15 @@ export const usePostBoostEstimation = ({
   post: postFromProps,
   query,
 }: UsePostBoostEstimationProps) => {
+  const { createdAt } = postFromProps;
+
+  if (!createdAt) {
+    throw new Error('usePostBoostEstimation requires post.createdAt');
+  }
+
   const isOldPost = useMemo(
-    () => isOlderThan(oneMinute * 5, new Date(postFromProps.createdAt)),
-    [postFromProps.createdAt],
+    () => isOlderThan(oneMinute * 5, new Date(createdAt)),
+    [createdAt],
   );
   const [retriesExhausted, setRetriesExhausted] = useState(false);
   const [post, setPost] = useState(postFromProps);
diff --git a/packages/shared/src/features/briefing/components/BriefPlusUpgradeCTA.tsx b/packages/shared/src/features/briefing/components/BriefPlusUpgradeCTA.tsx
index fbe37344842..07cf803d66d 100644
--- a/packages/shared/src/features/briefing/components/BriefPlusUpgradeCTA.tsx
+++ b/packages/shared/src/features/briefing/components/BriefPlusUpgradeCTA.tsx
@@ -15,7 +15,7 @@ import { useAuthContext } from '../../../contexts/AuthContext';
 export const BriefPlusUpgradeCTA = ({
   className,
   ...attrs
-}: ButtonProps<'a'> | undefined): ReactElement => {
+}: ButtonProps<'a'>): ReactElement => {
   const { isAuthReady } = useAuthContext();
   const { logSubscriptionEvent, isPlus } = usePlusSubscription();
   const {
diff --git a/packages/shared/src/features/briefing/hooks/useGenerateBrief.ts b/packages/shared/src/features/briefing/hooks/useGenerateBrief.ts
index ca75ba03dca..e595ad35c47 100644
--- a/packages/shared/src/features/briefing/hooks/useGenerateBrief.ts
+++ b/packages/shared/src/features/briefing/hooks/useGenerateBrief.ts
@@ -27,7 +27,7 @@ export const useGenerateBrief = ({ onGenerated }: UseGenerateBriefingProps) => {
     onSuccess: async ({ id, balance }) => {
       displayToast('Your Presidential Briefing is being generated ✅');
 
-      if (balance) {
+      if (balance && user) {
         updateUser({
           ...user,
           balance,
diff --git a/packages/shared/src/features/onboarding/hooks/useFunnelNavigation.ts b/packages/shared/src/features/onboarding/hooks/useFunnelNavigation.ts
index 3d038507aea..9b8193bdfeb 100644
--- a/packages/shared/src/features/onboarding/hooks/useFunnelNavigation.ts
+++ b/packages/shared/src/features/onboarding/hooks/useFunnelNavigation.ts
@@ -210,10 +210,17 @@ export const useFunnelNavigation = ({
     [setPosition, stepMap],
   );
 
-  const step: FunnelStep = useMemo(
-    () => getFunnelStepByPosition(funnel, position),
-    [funnel, position],
-  );
+  const step: FunnelStep = useMemo(() => {
+    const currentStep = getFunnelStepByPosition(funnel, position);
+
+    if (!currentStep) {
+      throw new Error(
+        'Failed to resolve funnel step from the current position',
+      );
+    }
+
+    return currentStep;
+  }, [funnel, position]);
   const navigationStateRef = useRef({ step, stepTimerStart });
   navigationStateRef.current = { step, stepTimerStart };
 
diff --git a/packages/shared/src/features/onboarding/hooks/useStepTransition.ts b/packages/shared/src/features/onboarding/hooks/useStepTransition.ts
index 07b23494ea3..51f8f30c3e5 100644
--- a/packages/shared/src/features/onboarding/hooks/useStepTransition.ts
+++ b/packages/shared/src/features/onboarding/hooks/useStepTransition.ts
@@ -38,7 +38,7 @@ export function useStepTransition(sessionId: string): UseStepTransitionRet {
   });
 
   return {
-    transition: mutateAsync,
+    transition: mutateAsync as UseStepTransitionRet['transition'],
     isPending,
   };
 }
diff --git a/packages/shared/src/features/onboarding/lib/utils.ts b/packages/shared/src/features/onboarding/lib/utils.ts
index 9120f8987ec..914a01a2ffd 100644
--- a/packages/shared/src/features/onboarding/lib/utils.ts
+++ b/packages/shared/src/features/onboarding/lib/utils.ts
@@ -59,7 +59,7 @@ export const getCookiesAndHeadersFromRequest = (
     },
   );
   if (!forwardedHeaders['x-forwarded-for']) {
-    forwardedHeaders['x-forwarded-for'] = req.socket.remoteAddress;
+    forwardedHeaders['x-forwarded-for'] = req.socket.remoteAddress ?? '';
   }
 
   return { cookies: allCookies, forwardedHeaders };
diff --git a/packages/shared/src/features/onboarding/shared/PricingPlan.tsx b/packages/shared/src/features/onboarding/shared/PricingPlan.tsx
index 4aa76cfce8a..ac7a00ac4a3 100644
--- a/packages/shared/src/features/onboarding/shared/PricingPlan.tsx
+++ b/packages/shared/src/features/onboarding/shared/PricingPlan.tsx
@@ -42,8 +42,9 @@ export function PricingPlan<T extends string = string>({
   const isBestValue = variation === PricingPlanVariation.BEST_VALUE;
   const baseClassName: RadioItemProps<T>['className'] = {
     wrapper:
-      isBestValue &&
-      `relative p-1 pt-8 rounded-16 overflow-hidden ${styles.bestValue}`,
+      (isBestValue &&
+        `relative p-1 pt-8 rounded-16 overflow-hidden ${styles.bestValue}`) ||
+      undefined,
     content: classNames(
       styles.label,
       'z-1 !items-start gap-2 overflow-hidden rounded-12 border p-3',
diff --git a/packages/shared/src/features/onboarding/shared/PricingPlans.tsx b/packages/shared/src/features/onboarding/shared/PricingPlans.tsx
index 4c5bde3e60b..7a3ee0f7610 100644
--- a/packages/shared/src/features/onboarding/shared/PricingPlans.tsx
+++ b/packages/shared/src/features/onboarding/shared/PricingPlans.tsx
@@ -23,18 +23,30 @@ export function PricingPlans<T extends string = string>({
 }: PricingPlansProps<T>): ReactElement {
   return (
     <div className={classNames('flex flex-col gap-2', className)}>
-      {plans.map((plan) => (
-        <PricingPlan
-          {...plan}
-          key={plan.value}
-          name={name}
-          id={`${name}-${plan.id || plan.value}`}
-          value={plan.value}
-          checked={value === plan.value}
-          onChange={() => onChange(plan.value)}
-          perks={perks}
-        />
-      ))}
+      {plans.map((plan) =>
+        (() => {
+          const planValue = plan.value;
+
+          if (!planValue) {
+            throw new Error(
+              'PricingPlans requires each plan to define a value',
+            );
+          }
+
+          return (
+            <PricingPlan
+              {...plan}
+              key={planValue}
+              name={name}
+              id={`${name}-${plan.id || planValue}`}
+              value={planValue}
+              checked={value === planValue}
+              onChange={() => onChange(planValue)}
+              perks={perks}
+            />
+          );
+        })(),
+      )}
     </div>
   );
 }
diff --git a/packages/shared/src/features/onboarding/shared/StepHeadline.tsx b/packages/shared/src/features/onboarding/shared/StepHeadline.tsx
index f6b3b4d9722..f054ed0b5f8 100644
--- a/packages/shared/src/features/onboarding/shared/StepHeadline.tsx
+++ b/packages/shared/src/features/onboarding/shared/StepHeadline.tsx
@@ -32,7 +32,10 @@ export const StepHeadline = ({
   className,
 }: StepHeadlineProps): ReactElement => {
   const titleHtml = useMemo(() => sanitizeMessage(heading), [heading]);
-  const descHtml = useMemo(() => sanitizeMessage(description), [description]);
+  const descHtml = useMemo(
+    () => (description ? sanitizeMessage(description) : undefined),
+    [description],
+  );
 
   return (
     <div
diff --git a/packages/shared/src/features/onboarding/steps/FunnelBrowserExtension.tsx b/packages/shared/src/features/onboarding/steps/FunnelBrowserExtension.tsx
index 9a3eff0a537..1891627b051 100644
--- a/packages/shared/src/features/onboarding/steps/FunnelBrowserExtension.tsx
+++ b/packages/shared/src/features/onboarding/steps/FunnelBrowserExtension.tsx
@@ -31,7 +31,10 @@ const BrowserExtension = ({
   const { logEvent } = useLogContext();
   const { browserName } = useOnboardingExtension();
   const isEdge = browserName === BrowserName.Edge;
-  const imageUrls = cloudinaryOnboardingExtension[browserName];
+  const imageUrls =
+    cloudinaryOnboardingExtension[
+      browserName as keyof typeof cloudinaryOnboardingExtension
+    ];
 
   return (
     <div className="mt-10 flex flex-1 flex-col laptop:justify-between">
diff --git a/packages/shared/src/features/onboarding/steps/FunnelCheckout.tsx b/packages/shared/src/features/onboarding/steps/FunnelCheckout.tsx
index 24bbfadd4a1..4d3913759af 100644
--- a/packages/shared/src/features/onboarding/steps/FunnelCheckout.tsx
+++ b/packages/shared/src/features/onboarding/steps/FunnelCheckout.tsx
@@ -40,6 +40,10 @@ export const FunnelCheckout = ({
 
     currentPriceIdRef.current = priceId;
 
+    if (!openCheckout) {
+      throw new Error('FunnelCheckout requires an available checkout handler');
+    }
+
     openCheckout({
       priceId,
       discountId: applyDiscount ? discountCode : undefined,
diff --git a/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactCentered.tsx b/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactCentered.tsx
index 20000e7981d..78933cbf5cf 100644
--- a/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactCentered.tsx
+++ b/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactCentered.tsx
@@ -33,7 +33,7 @@ export const FunnelFactCentered = (props: FunnelStepFact): ReactElement => {
     <Badge
       label={badge.cta}
       icon={<ReputationLightningIcon className="h-6 w-6" secondary />}
-      variant={badge.variant}
+      variant={badge.variant ?? 'primary'}
     />
   );
 
diff --git a/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactDefault.tsx b/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactDefault.tsx
index 5543c86e248..18c625b4332 100644
--- a/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactDefault.tsx
+++ b/packages/shared/src/features/onboarding/steps/FunnelFact/FunnelFactDefault.tsx
@@ -57,7 +57,7 @@ export const FunnelFactDefault = (props: FunnelStepFact): ReactElement => {
     <Badge
       label={badge.cta}
       icon={<ReputationLightningIcon className="h-6 w-6" secondary />}
-      variant={badge.variant}
+      variant={badge.variant ?? 'primary'}
     />
   );
 
diff --git a/packages/shared/src/features/onboarding/steps/FunnelPricing/FunnelPricing.spec.tsx b/packages/shared/src/features/onboarding/steps/FunnelPricing/FunnelPricing.spec.tsx
index dae73e2a29e..f9f0871601e 100644
--- a/packages/shared/src/features/onboarding/steps/FunnelPricing/FunnelPricing.spec.tsx
+++ b/packages/shared/src/features/onboarding/steps/FunnelPricing/FunnelPricing.spec.tsx
@@ -242,6 +242,10 @@ describe('FunnelPricing', () => {
     );
 
     // Click on the monthly plan
+    if (!monthlyPlan) {
+      throw new Error('Missing monthly plan radio button');
+    }
+
     fireEvent.click(monthlyPlan);
 
     // Then click the CTA
diff --git a/packages/shared/src/features/opportunity/components/CVExists.tsx b/packages/shared/src/features/opportunity/components/CVExists.tsx
index 7ae6fec2922..0fd678fbadf 100644
--- a/packages/shared/src/features/opportunity/components/CVExists.tsx
+++ b/packages/shared/src/features/opportunity/components/CVExists.tsx
@@ -18,6 +18,10 @@ export const CVExists = ({
   preferences: UserCandidatePreferences;
 }): ReactElement => {
   const { user } = useAuthContext();
+  const fileName =
+    preferences?.cv?.fileName ||
+    (user?.username ? `${user.username}.pdf` : 'resume.pdf');
+
   return (
     <div className="mx-auto mt-10 flex max-w-[42.5rem] flex-col items-center gap-6 rounded-16 border border-border-subtlest-secondary bg-blur-baseline p-6 tablet:w-full">
       <Typography type={TypographyType.LargeTitle} bold center>
@@ -45,7 +49,7 @@ export const CVExists = ({
         className="flex items-center gap-2"
       >
         <DocsIcon size={IconSize.Large} />
-        {preferences?.cv?.fileName ?? `${user.username}.pdf`}
+        {fileName}
       </Typography>
 
       <CandidatePreferenceButton targetId={TargetId.OpportunityWelcomePage} />
diff --git a/packages/shared/src/features/opportunity/components/ClearEmploymentAgreementButton.tsx b/packages/shared/src/features/opportunity/components/ClearEmploymentAgreementButton.tsx
index b5be548f979..8ea62c3d0b4 100644
--- a/packages/shared/src/features/opportunity/components/ClearEmploymentAgreementButton.tsx
+++ b/packages/shared/src/features/opportunity/components/ClearEmploymentAgreementButton.tsx
@@ -22,7 +22,8 @@ export const ClearEmploymentAgreementButton = (): ReactElement => {
   const { logEvent } = useLogContext();
   const { displayToast } = useToastNotification();
   const { completeAction } = useActions();
-  const opts = getCandidatePreferencesOptions(user?.id);
+
+  const opts = getCandidatePreferencesOptions(user?.id ?? '');
   const updateQuery = useUpdateQuery(opts);
 
   const { mutate: clearFile, isPending: isClearFilePending } = useMutation({
@@ -38,6 +39,11 @@ export const ClearEmploymentAgreementButton = (): ReactElement => {
       );
     },
   });
+
+  if (!user) {
+    return <></>;
+  }
+
   return (
     <Tooltip content="Remove uploaded employment agreement">
       <Button
diff --git a/packages/shared/src/features/opportunity/components/ClearResumeButton.tsx b/packages/shared/src/features/opportunity/components/ClearResumeButton.tsx
index 75411fe0077..745f41637fe 100644
--- a/packages/shared/src/features/opportunity/components/ClearResumeButton.tsx
+++ b/packages/shared/src/features/opportunity/components/ClearResumeButton.tsx
@@ -22,7 +22,8 @@ export const ClearResumeButton = (): ReactElement => {
   const { logEvent } = useLogContext();
   const { displayToast } = useToastNotification();
   const { completeAction } = useActions();
-  const opts = getCandidatePreferencesOptions(user?.id);
+
+  const opts = getCandidatePreferencesOptions(user?.id ?? '');
   const updateQuery = useUpdateQuery(opts);
 
   const { mutate: clearResume, isPending: isClearResumePending } = useMutation({
@@ -36,6 +37,11 @@ export const ClearResumeButton = (): ReactElement => {
       displayToast('Failed to remove uploaded CV. Please try again.');
     },
   });
+
+  if (!user) {
+    return <></>;
+  }
+
   return (
     <Tooltip content="Remove uploaded CV">
       <Button
diff --git a/packages/shared/src/features/opportunity/components/UploadEmploymentAgreementButton.tsx b/packages/shared/src/features/opportunity/components/UploadEmploymentAgreementButton.tsx
index f752454c16e..955958fe5df 100644
--- a/packages/shared/src/features/opportunity/components/UploadEmploymentAgreementButton.tsx
+++ b/packages/shared/src/features/opportunity/components/UploadEmploymentAgreementButton.tsx
@@ -22,7 +22,9 @@ export const UploadEmploymentAgreementButton = (): ReactElement => {
   const { logEvent } = useLogContext();
   const { displayToast } = useToastNotification();
 
-  const updateQuery = useUpdateQuery(getCandidatePreferencesOptions(user?.id));
+  const updateQuery = useUpdateQuery(
+    getCandidatePreferencesOptions(user?.id ?? ''),
+  );
 
   const { mutate: uploadEmploymentAgreement, isPending: isUploadPending } =
     useMutation({
@@ -49,6 +51,10 @@ export const UploadEmploymentAgreementButton = (): ReactElement => {
     [uploadEmploymentAgreement],
   );
 
+  if (!user) {
+    return <></>;
+  }
+
   return (
     <UploadButton
       className="mb-4 mr-auto"
diff --git a/packages/shared/src/features/organizations/components/LinksInput.tsx b/packages/shared/src/features/organizations/components/LinksInput.tsx
index 9fff7f49b38..2eb605b1d89 100644
--- a/packages/shared/src/features/organizations/components/LinksInput.tsx
+++ b/packages/shared/src/features/organizations/components/LinksInput.tsx
@@ -153,7 +153,11 @@ export const LinksInput = ({
             size={ButtonSize.XSmall}
             icon={<PlusIcon />}
             onClick={handleAdd}
-            disabled={!url.trim() || (isUnrecognized && !customLabel.trim())}
+            disabled={
+              !url.trim() ||
+              (isUnrecognized && !customLabel.trim()) ||
+              undefined
+            }
           >
             Add
           </Button>
diff --git a/packages/shared/src/features/organizations/components/Sidebar.tsx b/packages/shared/src/features/organizations/components/Sidebar.tsx
index 43a4e71fc2d..270f384b16b 100644
--- a/packages/shared/src/features/organizations/components/Sidebar.tsx
+++ b/packages/shared/src/features/organizations/components/Sidebar.tsx
@@ -23,7 +23,7 @@ import { InnerProfileSettingsMenu } from '../../../components/profile/ProfileSet
 type MenuItems = Record<
   string,
   {
-    title: string | null;
+    title: string | undefined;
     items: Record<string, ProfileSectionItemProps>;
   }
 >;
@@ -32,7 +32,7 @@ const defineMenuItems = <T extends MenuItems>(items: T): T => items;
 
 const menuItems = defineMenuItems({
   main: {
-    title: null,
+    title: undefined,
     items: {
       general: {
         title: 'General',
diff --git a/packages/shared/src/features/profile/components/Activity.helpers.tsx b/packages/shared/src/features/profile/components/Activity.helpers.tsx
index d557a3e1ed9..6b0e054ff0b 100644
--- a/packages/shared/src/features/profile/components/Activity.helpers.tsx
+++ b/packages/shared/src/features/profile/components/Activity.helpers.tsx
@@ -70,7 +70,7 @@ export const ACTIVITY_QUERY_KEYS = {
   posts: (userId: string) => ['author', userId] as const,
   upvoted: (userId: string) => [OtherFeedPage.UserUpvoted, userId] as const,
   comments: (userId: string) =>
-    generateQueryKey(RequestKey.UserComments, null, userId, 'activity'),
+    generateQueryKey(RequestKey.UserComments, undefined, userId, 'activity'),
 } as const;
 
 export const getItemCount = (
diff --git a/packages/shared/src/features/profile/components/ProfileCompany.tsx b/packages/shared/src/features/profile/components/ProfileCompany.tsx
index c42583f18d6..d551344f432 100644
--- a/packages/shared/src/features/profile/components/ProfileCompany.tsx
+++ b/packages/shared/src/features/profile/components/ProfileCompany.tsx
@@ -77,7 +77,10 @@ const ProfileCompany = ({
     }
   };
 
-  const [debouncedQuery] = useDebounceFn<string>((q) => handleSearch(q), 300);
+  const [debouncedQuery] = useDebounceFn<string>(
+    (q) => handleSearch(q ?? ''),
+    300,
+  );
 
   return (
     <div className="flex flex-col gap-1">
diff --git a/packages/shared/src/features/profile/components/ProfileGithubRepository.tsx b/packages/shared/src/features/profile/components/ProfileGithubRepository.tsx
index c180a832c96..2ecc6c49947 100644
--- a/packages/shared/src/features/profile/components/ProfileGithubRepository.tsx
+++ b/packages/shared/src/features/profile/components/ProfileGithubRepository.tsx
@@ -96,7 +96,10 @@ const ProfileGithubRepository = ({
     });
   };
 
-  const [debouncedQuery] = useDebounceFn<string>((q) => handleSearch(q), 300);
+  const [debouncedQuery] = useDebounceFn<string>(
+    (q) => handleSearch(q ?? ''),
+    300,
+  );
 
   const repositoryFullName = repository?.owner
     ? `${repository.owner}/${repository.name}`
diff --git a/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquads.spec.tsx b/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquads.spec.tsx
index 04a24716e92..c09ef2ef74e 100644
--- a/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquads.spec.tsx
+++ b/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquads.spec.tsx
@@ -146,7 +146,7 @@ const renderComponent = (
   if (recommendedSquads.length > 0) {
     const sourcesKey = generateQueryKey(
       RequestKey.Sources,
-      null,
+      undefined,
       undefined, // featured
       true, // isPublic
       undefined, // categoryId
diff --git a/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquadsComponents.tsx b/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquadsComponents.tsx
index 37b5d6a4020..446f4c10238 100644
--- a/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquadsComponents.tsx
+++ b/packages/shared/src/features/profile/components/ProfileWidgets/ActiveOrRecomendedSquadsComponents.tsx
@@ -81,7 +81,7 @@ export const SquadListItem = ({
           }}
           origin={Origin.Profile}
           size={ButtonSize.Small}
-          squad={{ ...squad, currentMember: null }}
+          squad={{ ...squad, currentMember: undefined }}
         />
       )}
     </li>
diff --git a/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.spec.tsx b/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.spec.tsx
index 1e3d509619b..c7b6a0e135e 100644
--- a/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.spec.tsx
+++ b/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.spec.tsx
@@ -35,20 +35,27 @@ const defaultUser: PublicProfile = {
   image: 'https://daily.dev/test.png',
   bio: 'Test bio',
   createdAt: '2020-01-01T00:00:00.000Z',
-  twitter: 'testuser',
-  github: 'testuser',
-  hashnode: 'testuser',
-  portfolio: 'https://test.com',
   permalink: 'https://daily.dev/testuser',
-  roadmap: 'testuser',
-  threads: 'testuser',
-  codepen: 'testuser',
-  reddit: 'testuser',
-  stackoverflow: '123456/testuser',
-  youtube: 'testuser',
-  linkedin: 'testuser',
-  mastodon: 'https://mastodon.social/@testuser',
-  bluesky: 'testuser.bsky.social',
+  socialLinks: [
+    { platform: 'github', url: 'https://github.com/testuser' },
+    { platform: 'hashnode', url: 'https://hashnode.com/testuser' },
+    { platform: 'portfolio', url: 'https://test.com' },
+    { platform: 'roadmap', url: 'https://roadmap.sh/testuser' },
+    { platform: 'threads', url: 'https://threads.net/testuser' },
+    { platform: 'codepen', url: 'https://codepen.io/testuser' },
+    { platform: 'reddit', url: 'https://reddit.com/u/testuser' },
+    {
+      platform: 'stackoverflow',
+      url: 'https://stackoverflow.com/users/123456/testuser',
+    },
+    { platform: 'youtube', url: 'https://youtube.com/testuser' },
+    { platform: 'linkedin', url: 'https://linkedin.com/in/testuser' },
+    { platform: 'mastodon', url: 'https://mastodon.social/@testuser' },
+    {
+      platform: 'bluesky',
+      url: 'https://bsky.app/profile/testuser.bsky.social',
+    },
+  ],
 };
 
 const mockTopReaders = [
diff --git a/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.tsx b/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.tsx
index c6964ca50c5..6d800232861 100644
--- a/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.tsx
+++ b/packages/shared/src/features/profile/components/ProfileWidgets/BadgesAndAwards.tsx
@@ -29,7 +29,7 @@ export const BadgesAndAwards = ({
   user,
 }: {
   user: PublicProfile;
-}): ReactElement => {
+}): ReactElement | null => {
   const { data: topReaders, isPending: isTopReaderLoading } = useTopReader({
     user,
     limit: 5,
diff --git a/packages/shared/src/features/profile/components/ProfileWidgets/ProfileCompletion.spec.tsx b/packages/shared/src/features/profile/components/ProfileWidgets/ProfileCompletion.spec.tsx
index 32778fca44d..6b89eacd90f 100644
--- a/packages/shared/src/features/profile/components/ProfileWidgets/ProfileCompletion.spec.tsx
+++ b/packages/shared/src/features/profile/components/ProfileWidgets/ProfileCompletion.spec.tsx
@@ -38,16 +38,14 @@ const renderWithAuth = (user: LoggedUser | null) => {
   return render(
     <QueryClientProvider client={queryClient}>
       <AuthContextProvider
-        user={user}
+        user={user ?? undefined}
         updateUser={jest.fn()}
         tokenRefreshed
         getRedirectUri={jest.fn()}
-        closeLogin={jest.fn()}
         loadingUser={false}
         loadedUserFromCache
         refetchBoot={jest.fn()}
         firstLoad={false}
-        isValidSession
       >
         <ProfileCompletion />
       </AuthContextProvider>
diff --git a/packages/shared/src/features/profile/components/ProfileWidgets/Share.tsx b/packages/shared/src/features/profile/components/ProfileWidgets/Share.tsx
index 41abc30d483..a67126b8efe 100644
--- a/packages/shared/src/features/profile/components/ProfileWidgets/Share.tsx
+++ b/packages/shared/src/features/profile/components/ProfileWidgets/Share.tsx
@@ -170,7 +170,7 @@ export const Share = ({ permalink, className }: ShareProps): ReactElement => {
             />
           </Tooltip>
         ))}
-        {globalThis?.navigator?.share && (
+        {!!globalThis?.navigator?.share && (
           <Tooltip content="Share via...">
             <Button
               variant={ButtonVariant.Tertiary}
diff --git a/packages/shared/src/features/profile/components/experience/DeleteExperienceButton.tsx b/packages/shared/src/features/profile/components/experience/DeleteExperienceButton.tsx
index 3d635442cdc..62c8fd66566 100644
--- a/packages/shared/src/features/profile/components/experience/DeleteExperienceButton.tsx
+++ b/packages/shared/src/features/profile/components/experience/DeleteExperienceButton.tsx
@@ -35,7 +35,7 @@ const DeleteExperienceButton = ({
   experienceType,
 }: DeleteExperienceButtonProps): React.ReactElement => {
   const { removeExperience, isPending } = useRemoveExperience({
-    type: experienceType,
+    type: experienceType ?? UserExperienceType.Work,
   });
   const { showPrompt } = usePrompt();
 
diff --git a/packages/shared/src/features/profile/components/experience/forms/UserCertificationForm.spec.tsx b/packages/shared/src/features/profile/components/experience/forms/UserCertificationForm.spec.tsx
index 8e85d84c039..c4f68bd2241 100644
--- a/packages/shared/src/features/profile/components/experience/forms/UserCertificationForm.spec.tsx
+++ b/packages/shared/src/features/profile/components/experience/forms/UserCertificationForm.spec.tsx
@@ -338,7 +338,7 @@ describe('UserCertificationForm', () => {
     const descriptionTextarea = getFieldByName(
       container,
       'description',
-    ) as HTMLTextAreaElement;
+    ) as unknown as HTMLTextAreaElement;
 
     // Textarea has a 5000 character limit
     const description =
diff --git a/packages/shared/src/features/profile/components/experience/forms/UserEducationForm.spec.tsx b/packages/shared/src/features/profile/components/experience/forms/UserEducationForm.spec.tsx
index 70f5a71e9d2..0cc5fe8ab35 100644
--- a/packages/shared/src/features/profile/components/experience/forms/UserEducationForm.spec.tsx
+++ b/packages/shared/src/features/profile/components/experience/forms/UserEducationForm.spec.tsx
@@ -313,7 +313,7 @@ describe('UserEducationForm', () => {
     const descriptionTextarea = getFieldByName(
       container,
       'description',
-    ) as HTMLTextAreaElement;
+    ) as unknown as HTMLTextAreaElement;
 
     // Textarea has a 5000 character limit
     const description =
diff --git a/packages/shared/src/features/profile/components/gear/GearModal.spec.tsx b/packages/shared/src/features/profile/components/gear/GearModal.spec.tsx
index c7ca5133190..346c99d364e 100644
--- a/packages/shared/src/features/profile/components/gear/GearModal.spec.tsx
+++ b/packages/shared/src/features/profile/components/gear/GearModal.spec.tsx
@@ -25,7 +25,7 @@ describe('GearModal', () => {
     mockUseGearSearch.mockReturnValue({
       results: [],
       isSearching: false,
-    } as ReturnType<typeof useGearSearch>);
+    } as unknown as ReturnType<typeof useGearSearch>);
     mockUseViewSize.mockReturnValue(false);
   });
 
@@ -50,7 +50,7 @@ describe('GearModal', () => {
     });
     expect(onSubmit).toHaveBeenCalledTimes(1);
     expect(onRequestClose).toHaveBeenCalledTimes(1);
-    expect(onRequestClose).toHaveBeenCalledWith(null);
+    expect(onRequestClose).toHaveBeenCalledWith(undefined);
   });
 
   it('should submit and close when clicking add gear button', async () => {
@@ -75,6 +75,6 @@ describe('GearModal', () => {
     });
     expect(onSubmit).toHaveBeenCalledTimes(1);
     expect(onRequestClose).toHaveBeenCalledTimes(1);
-    expect(onRequestClose).toHaveBeenCalledWith(null);
+    expect(onRequestClose).toHaveBeenCalledWith(undefined);
   });
 });
diff --git a/packages/shared/src/features/profile/components/gear/GearModal.tsx b/packages/shared/src/features/profile/components/gear/GearModal.tsx
index 4540c649e4f..cd562434af4 100644
--- a/packages/shared/src/features/profile/components/gear/GearModal.tsx
+++ b/packages/shared/src/features/profile/components/gear/GearModal.tsx
@@ -3,7 +3,10 @@ import React, { useMemo, useState } from 'react';
 import { FormProvider, useForm } from 'react-hook-form';
 import { z } from 'zod';
 import { zodResolver } from '@hookform/resolvers/zod';
-import type { ModalProps } from '../../../../components/modals/common/Modal';
+import type {
+  LazyModalCommonProps,
+  ModalProps,
+} from '../../../../components/modals/common/Modal';
 import { Modal } from '../../../../components/modals/common/Modal';
 import { TextField } from '../../../../components/fields/TextField';
 import { Button, ButtonVariant } from '../../../../components/buttons/Button';
@@ -18,7 +21,8 @@ const gearFormSchema = z.object({
 
 type GearFormData = z.infer<typeof gearFormSchema>;
 
-type GearModalProps = Omit<ModalProps, 'children'> & {
+type GearModalProps = Omit<ModalProps, 'children' | 'onRequestClose'> & {
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
   onSubmit: (input: AddGearInput) => Promise<void>;
 };
 
@@ -57,7 +61,7 @@ export function GearModal({ onSubmit, ...rest }: GearModalProps): ReactElement {
     await onSubmit({
       name: data.name.trim(),
     });
-    rest.onRequestClose?.(null);
+    rest.onRequestClose?.(undefined);
   });
 
   const filteredSuggestions = useMemo(() => {
diff --git a/packages/shared/src/features/profile/components/hotTakes/HotTakeModal.tsx b/packages/shared/src/features/profile/components/hotTakes/HotTakeModal.tsx
index aef305ff97b..d913078a653 100644
--- a/packages/shared/src/features/profile/components/hotTakes/HotTakeModal.tsx
+++ b/packages/shared/src/features/profile/components/hotTakes/HotTakeModal.tsx
@@ -4,7 +4,10 @@ import { Controller, FormProvider, useForm } from 'react-hook-form';
 import { z } from 'zod';
 import { zodResolver } from '@hookform/resolvers/zod';
 import dynamic from 'next/dynamic';
-import type { ModalProps } from '../../../../components/modals/common/Modal';
+import type {
+  LazyModalCommonProps,
+  ModalProps,
+} from '../../../../components/modals/common/Modal';
 import { Modal } from '../../../../components/modals/common/Modal';
 import { TextField } from '../../../../components/fields/TextField';
 import { Button, ButtonVariant } from '../../../../components/buttons/Button';
@@ -31,7 +34,8 @@ const hotTakeFormSchema = z.object({
 
 type HotTakeFormData = z.infer<typeof hotTakeFormSchema>;
 
-type HotTakeModalProps = Omit<ModalProps, 'children'> & {
+type HotTakeModalProps = Omit<ModalProps, 'children' | 'onRequestClose'> & {
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
   onSubmit: (input: AddHotTakeInput) => Promise<void>;
   existingItem?: HotTake;
 };
@@ -71,7 +75,7 @@ export function HotTakeModal({
       title: data.title.trim(),
       subtitle: data.subtitle?.trim() || undefined,
     });
-    rest.onRequestClose?.(null);
+    rest.onRequestClose?.(undefined);
   });
 
   return (
diff --git a/packages/shared/src/features/profile/components/stack/UserStackModal.tsx b/packages/shared/src/features/profile/components/stack/UserStackModal.tsx
index c5dcdd4f8e2..ac2db959584 100644
--- a/packages/shared/src/features/profile/components/stack/UserStackModal.tsx
+++ b/packages/shared/src/features/profile/components/stack/UserStackModal.tsx
@@ -3,7 +3,10 @@ import React, { useMemo, useState } from 'react';
 import { Controller, FormProvider, useForm } from 'react-hook-form';
 import { z } from 'zod';
 import { zodResolver } from '@hookform/resolvers/zod';
-import type { ModalProps } from '../../../../components/modals/common/Modal';
+import type {
+  LazyModalCommonProps,
+  ModalProps,
+} from '../../../../components/modals/common/Modal';
 import { Modal } from '../../../../components/modals/common/Modal';
 import { TextField } from '../../../../components/fields/TextField';
 import {
@@ -39,7 +42,8 @@ const userStackFormSchema = z.object({
 
 type UserStackFormData = z.infer<typeof userStackFormSchema>;
 
-type UserStackModalProps = Omit<ModalProps, 'children'> & {
+type UserStackModalProps = Omit<ModalProps, 'children' | 'onRequestClose'> & {
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
   onSubmit: (input: AddUserStackInput) => Promise<void>;
   existingItem?: UserStack;
 };
@@ -113,7 +117,7 @@ export function UserStackModal({
       section: effectiveSection.trim(),
       startedAt: startedAtValue,
     });
-    rest.onRequestClose?.(null);
+    rest.onRequestClose?.(undefined);
   });
 
   const filteredSuggestions = useMemo(() => {
diff --git a/packages/shared/src/features/profile/components/workspacePhotos/WorkspacePhotoUploadModal.tsx b/packages/shared/src/features/profile/components/workspacePhotos/WorkspacePhotoUploadModal.tsx
index 59b437ccab9..91b7a21f6ba 100644
--- a/packages/shared/src/features/profile/components/workspacePhotos/WorkspacePhotoUploadModal.tsx
+++ b/packages/shared/src/features/profile/components/workspacePhotos/WorkspacePhotoUploadModal.tsx
@@ -1,7 +1,10 @@
 import type { ReactElement, ChangeEvent, DragEvent } from 'react';
 import React, { useState, useRef, useCallback } from 'react';
 import classNames from 'classnames';
-import type { ModalProps } from '../../../../components/modals/common/Modal';
+import type {
+  LazyModalCommonProps,
+  ModalProps,
+} from '../../../../components/modals/common/Modal';
 import { Modal } from '../../../../components/modals/common/Modal';
 import { Button, ButtonVariant } from '../../../../components/buttons/Button';
 import { ModalHeader } from '../../../../components/modals/common/ModalHeader';
@@ -20,7 +23,11 @@ import {
 } from '../../../../graphql/posts';
 import type { AddUserWorkspacePhotoInput } from '../../../../graphql/user/userWorkspacePhoto';
 
-type WorkspacePhotoUploadModalProps = Omit<ModalProps, 'children'> & {
+type WorkspacePhotoUploadModalProps = Omit<
+  ModalProps,
+  'children' | 'onRequestClose'
+> & {
+  onRequestClose?: LazyModalCommonProps['onRequestClose'];
   onSubmit: (input: AddUserWorkspacePhotoInput) => Promise<void>;
 };
 
@@ -102,7 +109,7 @@ export function WorkspacePhotoUploadModal({
     try {
       const imageUrl = await uploadContentImage(selectedFile);
       await onSubmit({ image: imageUrl });
-      rest.onRequestClose?.(null);
+      rest.onRequestClose?.(undefined);
     } catch (err) {
       setError('Failed to upload image. Please try again.');
     } finally {
diff --git a/packages/shared/src/features/profile/hooks/useGear.ts b/packages/shared/src/features/profile/hooks/useGear.ts
index b6ecab8e033..409f2082804 100644
--- a/packages/shared/src/features/profile/hooks/useGear.ts
+++ b/packages/shared/src/features/profile/hooks/useGear.ts
@@ -22,7 +22,11 @@ export function useGear(user: PublicProfile | null) {
   const { logEvent } = useLogContext();
   const isOwner = loggedUser?.id === user?.id;
 
-  const queryKey = generateQueryKey(RequestKey.Gear, user, 'profile');
+  const queryKey = generateQueryKey(
+    RequestKey.Gear,
+    user ?? undefined,
+    'profile',
+  );
 
   const query = useQuery({
     queryKey,
diff --git a/packages/shared/src/features/profile/hooks/useGearSearch.ts b/packages/shared/src/features/profile/hooks/useGearSearch.ts
index 1c44af8c2d3..a4407a4ba21 100644
--- a/packages/shared/src/features/profile/hooks/useGearSearch.ts
+++ b/packages/shared/src/features/profile/hooks/useGearSearch.ts
@@ -7,7 +7,11 @@ export function useGearSearch(query: string) {
   const trimmedQuery = query.trim();
   const enabled = trimmedQuery.length >= 1;
 
-  const queryKey = generateQueryKey(RequestKey.GearSearch, null, trimmedQuery);
+  const queryKey = generateQueryKey(
+    RequestKey.GearSearch,
+    undefined,
+    trimmedQuery,
+  );
 
   const searchQuery = useQuery<DatasetGear[]>({
     queryKey,
diff --git a/packages/shared/src/features/profile/hooks/useHotTakes.ts b/packages/shared/src/features/profile/hooks/useHotTakes.ts
index be6606449c1..2200ff8b2f0 100644
--- a/packages/shared/src/features/profile/hooks/useHotTakes.ts
+++ b/packages/shared/src/features/profile/hooks/useHotTakes.ts
@@ -25,7 +25,11 @@ export const useHotTakes = (user: PublicProfile | null) => {
   const { isOwner } = useProfilePreview(user);
   const { logEvent } = useLogContext();
 
-  const queryKey = generateQueryKey(RequestKey.UserHotTakes, user, 'profile');
+  const queryKey = generateQueryKey(
+    RequestKey.UserHotTakes,
+    user ?? undefined,
+    'profile',
+  );
 
   const query = useQuery({
     queryKey,
diff --git a/packages/shared/src/features/profile/hooks/useStackSearch.ts b/packages/shared/src/features/profile/hooks/useStackSearch.ts
index 3b33c2d83b6..7ae260c8569 100644
--- a/packages/shared/src/features/profile/hooks/useStackSearch.ts
+++ b/packages/shared/src/features/profile/hooks/useStackSearch.ts
@@ -12,7 +12,7 @@ export function useStackSearch(query: string) {
 
   const queryKey = generateQueryKey(
     RequestKey.StackSearch,
-    null,
+    undefined,
     debouncedQuery,
   );
 
diff --git a/packages/shared/src/features/profile/hooks/useToolSearch.ts b/packages/shared/src/features/profile/hooks/useToolSearch.ts
index 76154c5aeff..8ec13d54b98 100644
--- a/packages/shared/src/features/profile/hooks/useToolSearch.ts
+++ b/packages/shared/src/features/profile/hooks/useToolSearch.ts
@@ -12,7 +12,7 @@ export function useToolSearch(query: string) {
 
   const queryKey = generateQueryKey(
     RequestKey.ToolSearch,
-    null,
+    undefined,
     debouncedQuery,
   );
 
diff --git a/packages/shared/src/features/profile/hooks/useToolTopSquads.ts b/packages/shared/src/features/profile/hooks/useToolTopSquads.ts
index 8806c1c5ffb..94d6fc2a650 100644
--- a/packages/shared/src/features/profile/hooks/useToolTopSquads.ts
+++ b/packages/shared/src/features/profile/hooks/useToolTopSquads.ts
@@ -25,7 +25,7 @@ export const useToolTopSquads = ({
   const query = useQuery({
     queryKey: generateQueryKey(
       RequestKey.UserTools,
-      null,
+      undefined,
       'top-squads-by-tool',
       toolId,
       TOP_TOOL_SQUADS_LIMIT,
diff --git a/packages/shared/src/features/profile/hooks/useUserExperiencesByType.ts b/packages/shared/src/features/profile/hooks/useUserExperiencesByType.ts
index 2b239188178..c15d3fc3cdb 100644
--- a/packages/shared/src/features/profile/hooks/useUserExperiencesByType.ts
+++ b/packages/shared/src/features/profile/hooks/useUserExperiencesByType.ts
@@ -22,6 +22,7 @@ export function useUserExperiencesByType(
     queryKey,
     queryFn: () => getUserExperiencesByType(userId, type),
     staleTime: StaleTime.Default,
+    enabled: !!userId,
   });
 
   const experiences: UserExperience[] | undefined = useMemo(
diff --git a/packages/shared/src/features/profile/hooks/useUserStack.ts b/packages/shared/src/features/profile/hooks/useUserStack.ts
index c7de68d7ebf..269157f237d 100644
--- a/packages/shared/src/features/profile/hooks/useUserStack.ts
+++ b/packages/shared/src/features/profile/hooks/useUserStack.ts
@@ -25,7 +25,11 @@ export function useUserStack(user: PublicProfile | null) {
   const { isOwner } = useProfilePreview(user);
   const { logEvent } = useLogContext();
 
-  const queryKey = generateQueryKey(RequestKey.UserStack, user, 'profile');
+  const queryKey = generateQueryKey(
+    RequestKey.UserStack,
+    user ?? undefined,
+    'profile',
+  );
 
   const query = useQuery({
     queryKey,
diff --git a/packages/shared/src/features/profile/hooks/useUserWorkspacePhotos.ts b/packages/shared/src/features/profile/hooks/useUserWorkspacePhotos.ts
index 24ffdfad66a..1c40e47e930 100644
--- a/packages/shared/src/features/profile/hooks/useUserWorkspacePhotos.ts
+++ b/packages/shared/src/features/profile/hooks/useUserWorkspacePhotos.ts
@@ -25,7 +25,7 @@ export function useUserWorkspacePhotos(user: PublicProfile | null) {
 
   const queryKey = generateQueryKey(
     RequestKey.UserWorkspacePhotos,
-    user,
+    user ?? undefined,
     'profile',
   );
 
diff --git a/packages/shared/src/features/recruiter/components/OnboardingView.tsx b/packages/shared/src/features/recruiter/components/OnboardingView.tsx
index 71a62cfc8ad..279fb869ed2 100644
--- a/packages/shared/src/features/recruiter/components/OnboardingView.tsx
+++ b/packages/shared/src/features/recruiter/components/OnboardingView.tsx
@@ -1,21 +1,28 @@
-import type { ReactElement } from 'react';
+import type { ReactElement, ComponentType, ReactNode } from 'react';
 import React from 'react';
 import { RecruiterHeader } from '../../../components/recruiter/Header';
 import {
   RecruiterProgress,
   RecruiterProgressStep,
 } from '../../../components/recruiter/Progress';
+import type { OpportunityPreviewContextType } from '../../opportunity/context/OpportunityPreviewContext';
 import { OpportunityPreviewProvider } from '../../opportunity/context/OpportunityPreviewContext';
 import { AnalyzeContent } from '../../opportunity/components/analyze/AnalyzeContent';
 
+const PreviewProviderWithMock =
+  OpportunityPreviewProvider as unknown as ComponentType<{
+    children?: ReactNode;
+    mockData?: OpportunityPreviewContextType;
+  }>;
+
 export const OnboardingView = (): ReactElement => {
   return (
-    <OpportunityPreviewProvider mockData={{}}>
+    <PreviewProviderWithMock mockData={{} as OpportunityPreviewContextType}>
       <div className="pointer-events-none flex flex-1 flex-col blur-sm">
         <RecruiterHeader />
         <RecruiterProgress activeStep={RecruiterProgressStep.AnalyzeAndMatch} />
         <AnalyzeContent loadingStep={0} />
       </div>
-    </OpportunityPreviewProvider>
+    </PreviewProviderWithMock>
   );
 };
diff --git a/packages/shared/src/features/shortcuts/contexts/ShortcutsProvider.tsx b/packages/shared/src/features/shortcuts/contexts/ShortcutsProvider.tsx
index a7550df51da..933dec44bfd 100644
--- a/packages/shared/src/features/shortcuts/contexts/ShortcutsProvider.tsx
+++ b/packages/shared/src/features/shortcuts/contexts/ShortcutsProvider.tsx
@@ -38,7 +38,7 @@ const [ShortcutsProvider, useShortcuts] = createContextProvider(
     }, [hasCheckedPermission, topSites?.length]);
 
     useEffect(() => {
-      if (customLinks?.length > 0 && !isManual) {
+      if ((customLinks?.length ?? 0) > 0 && !isManual) {
         setIsManual(true);
       }
     }, [customLinks, isManual]);
diff --git a/packages/shared/src/hooks/auth/useIsSpecialUser.ts b/packages/shared/src/hooks/auth/useIsSpecialUser.ts
index d20fe86e103..d76901c8ec8 100644
--- a/packages/shared/src/hooks/auth/useIsSpecialUser.ts
+++ b/packages/shared/src/hooks/auth/useIsSpecialUser.ts
@@ -16,7 +16,7 @@ export const useIsSpecialUser = ({
   return useMemo(() => {
     return isSpecialUser({
       userId,
-      loggedUserId: user?.id,
+      loggedUserId: user?.id ?? null,
     });
   }, [userId, user?.id]);
 };
diff --git a/packages/shared/src/hooks/auth/useSignBack.ts b/packages/shared/src/hooks/auth/useSignBack.ts
index 77db70f603d..c6fd142cfab 100644
--- a/packages/shared/src/hooks/auth/useSignBack.ts
+++ b/packages/shared/src/hooks/auth/useSignBack.ts
@@ -41,7 +41,7 @@ export const useSignBack = (): UseSignBack => {
       }
 
       if (isNullOrUndefined(user)) {
-        return setSignBack(undefined);
+        return setSignBack(undefined as unknown as SignedInUser);
       }
 
       const { name, email, image } = user;
diff --git a/packages/shared/src/hooks/bookmark/useBookmarkReminderCover.ts b/packages/shared/src/hooks/bookmark/useBookmarkReminderCover.ts
index 2d44837d509..3707c8b086d 100644
--- a/packages/shared/src/hooks/bookmark/useBookmarkReminderCover.ts
+++ b/packages/shared/src/hooks/bookmark/useBookmarkReminderCover.ts
@@ -1,7 +1,7 @@
 import { useJustBookmarked } from './useJustBookmarked';
 import type { Post } from '../../graphql/posts';
 
-export const useBookmarkReminderCover = (post: Post): boolean => {
+export const useBookmarkReminderCover = (post?: Post): boolean => {
   const { justBookmarked } = useJustBookmarked({
     bookmarked: post?.bookmarked ?? false,
   });
diff --git a/packages/shared/src/hooks/comments/useCommentById.ts b/packages/shared/src/hooks/comments/useCommentById.ts
index 9e80d0a8c24..bd919038900 100644
--- a/packages/shared/src/hooks/comments/useCommentById.ts
+++ b/packages/shared/src/hooks/comments/useCommentById.ts
@@ -30,6 +30,11 @@ const useCommentById = ({
   const { user } = useAuthContext();
   const { requestMethod } = useRequestProtocol();
   const client = useQueryClient();
+
+  if (!requestMethod) {
+    throw new Error('Request method is required in useCommentById');
+  }
+
   const {
     data: commentById,
     isError,
diff --git a/packages/shared/src/hooks/contentPreference/useSearchSuggestionsContentPreferenceMutationSubscription.ts b/packages/shared/src/hooks/contentPreference/useSearchSuggestionsContentPreferenceMutationSubscription.ts
index de2d0e81b1a..20fcc6d37a0 100644
--- a/packages/shared/src/hooks/contentPreference/useSearchSuggestionsContentPreferenceMutationSubscription.ts
+++ b/packages/shared/src/hooks/contentPreference/useSearchSuggestionsContentPreferenceMutationSubscription.ts
@@ -40,24 +40,24 @@ export const useUseSearchSuggestionsContentPreferenceMutationSubscription = ({
       const { id: entityId } =
         mutationVariables as Parameters<ContentPreferenceMutation>[0];
 
-      mutationQueryClient.setQueryData<SearchSuggestionResult | undefined>(
+      mutationQueryClient.setQueryData(
         queryKey,
-        (data) => {
+        (data: SearchSuggestionResult | undefined) => {
           if (!data) {
             return data;
           }
 
-          const newData = {
+          const newData: SearchSuggestionResult = {
             ...data,
             hits: data.hits?.map((hit) => {
               if (hit.id === entityId) {
                 return {
                   ...hit,
                   contentPreference: nextStatus
-                    ? {
+                    ? ({
                         ...hit.contentPreference,
                         status: nextStatus,
-                      }
+                      } as typeof hit.contentPreference)
                     : undefined,
                 };
               }
diff --git a/packages/shared/src/hooks/contentPreference/useSourceContentPreferenceMutationSubscription.ts b/packages/shared/src/hooks/contentPreference/useSourceContentPreferenceMutationSubscription.ts
index d21adc9d825..4669d2cc4c1 100644
--- a/packages/shared/src/hooks/contentPreference/useSourceContentPreferenceMutationSubscription.ts
+++ b/packages/shared/src/hooks/contentPreference/useSourceContentPreferenceMutationSubscription.ts
@@ -53,10 +53,10 @@ export const useSourceContentPreferenceMutationSubscription = ({
 
         if (followedMember?.user) {
           followedMember.user.contentPreference = nextStatus
-            ? {
+            ? ({
                 ...followedMember.user.contentPreference,
                 status: nextStatus,
-              }
+              } as typeof followedMember.user.contentPreference)
             : undefined;
         }
 
diff --git a/packages/shared/src/hooks/feed/useCardCover.tsx b/packages/shared/src/hooks/feed/useCardCover.tsx
index d9362a2b8fb..9139d7dd355 100644
--- a/packages/shared/src/hooks/feed/useCardCover.tsx
+++ b/packages/shared/src/hooks/feed/useCardCover.tsx
@@ -15,7 +15,7 @@ interface UseCardCover {
 }
 
 interface UseCardCoverProps {
-  post: Post;
+  post?: Post;
   onShare?: (post: Post) => void;
   className?: {
     bookmark?: {
@@ -33,6 +33,10 @@ export const useCardCover = ({
   const shouldShowReminder = useBookmarkReminderCover(post);
 
   const overlay = useMemo(() => {
+    if (!post) {
+      return undefined;
+    }
+
     if (interaction === 'copy') {
       return (
         <CardCoverContainer title="Why not share it on social, too?">
diff --git a/packages/shared/src/hooks/feed/useCustomDefaultFeed.ts b/packages/shared/src/hooks/feed/useCustomDefaultFeed.ts
index 5841ef2c379..160c3467bbb 100644
--- a/packages/shared/src/hooks/feed/useCustomDefaultFeed.ts
+++ b/packages/shared/src/hooks/feed/useCustomDefaultFeed.ts
@@ -12,7 +12,7 @@ const useCustomDefaultFeed = (): UseCustomDefaultFeed => {
     isCustomDefaultFeed: !!(
       user?.defaultFeedId && user.defaultFeedId !== user?.id
     ),
-    defaultFeedId: user?.defaultFeedId ?? user?.id,
+    defaultFeedId: user?.defaultFeedId ?? user?.id ?? '',
   };
 };
 
diff --git a/packages/shared/src/hooks/input/useDebouncedUrl.ts b/packages/shared/src/hooks/input/useDebouncedUrl.ts
index 50d291db503..50b79c32ded 100644
--- a/packages/shared/src/hooks/input/useDebouncedUrl.ts
+++ b/packages/shared/src/hooks/input/useDebouncedUrl.ts
@@ -7,9 +7,9 @@ export const useDebouncedUrl = (
   onValidate: StartFn<string, boolean>,
   delay = 1000,
 ): [StartFn<string>, CancelEvent] =>
-  useDebounceFn((value: string) => {
-    if (!isValidHttpUrl(value) || !onValidate(value)) {
-      return null;
+  useDebounceFn((value?: string) => {
+    if (!value || !isValidHttpUrl(value) || !onValidate(value)) {
+      return undefined;
     }
 
     return callback(value);
diff --git a/packages/shared/src/hooks/input/useDiscardPost.ts b/packages/shared/src/hooks/input/useDiscardPost.ts
index aa2aa65ddab..26cbeb40876 100644
--- a/packages/shared/src/hooks/input/useDiscardPost.ts
+++ b/packages/shared/src/hooks/input/useDiscardPost.ts
@@ -24,7 +24,7 @@ interface UseDiscardPostProps {
 interface UseDiscardPost
   extends UseExitConfirmation,
     Pick<WritePostProps, 'draft' | 'updateDraft'> {
-  formRef: MutableRefObject<HTMLFormElement>;
+  formRef: MutableRefObject<HTMLFormElement | undefined>;
   isDraftReady: boolean;
   clearDraft: () => void;
   isUpdatingDraft: boolean;
diff --git a/packages/shared/src/hooks/integrations/useSourceIntegrationQuery.ts b/packages/shared/src/hooks/integrations/useSourceIntegrationQuery.ts
index de62c1989b2..72d56cc5be8 100644
--- a/packages/shared/src/hooks/integrations/useSourceIntegrationQuery.ts
+++ b/packages/shared/src/hooks/integrations/useSourceIntegrationQuery.ts
@@ -49,7 +49,7 @@ export const useSourceIntegrationQuery = ({
         const errorCode = error.response?.errors?.[0]?.extensions?.code;
 
         if ([ApiError.NotFound, ApiError.Forbidden].includes(errorCode)) {
-          return null;
+          return null as unknown as UserSourceIntegration;
         }
 
         throw originalError;
diff --git a/packages/shared/src/hooks/log/useDeviceId.ts b/packages/shared/src/hooks/log/useDeviceId.ts
index 869fa8c83ed..760186fef40 100644
--- a/packages/shared/src/hooks/log/useDeviceId.ts
+++ b/packages/shared/src/hooks/log/useDeviceId.ts
@@ -15,7 +15,7 @@ export const getOrGenerateDeviceId = async (): Promise<string> => {
 };
 
 export default function useDeviceId(): string {
-  const [deviceId, setDeviceId] = useState<string>();
+  const [deviceId, setDeviceId] = useState<string>('');
 
   useEffect(() => {
     getOrGenerateDeviceId().then((_deviceId) => setDeviceId(_deviceId));
diff --git a/packages/shared/src/hooks/log/useLogContextData.ts b/packages/shared/src/hooks/log/useLogContextData.ts
index e23fc7dc4cb..ba041364fdd 100644
--- a/packages/shared/src/hooks/log/useLogContextData.ts
+++ b/packages/shared/src/hooks/log/useLogContextData.ts
@@ -69,6 +69,10 @@ export default function useLogContextData(
       logEventEnd(id, now = new Date()) {
         const event = durationEventsQueue.current.get(id);
         if (event) {
+          if (!event.event_timestamp) {
+            throw new Error('Missing event timestamp for duration event');
+          }
+
           durationEventsQueue.current.delete(id);
           event.event_duration =
             now.getTime() - event.event_timestamp.getTime();
diff --git a/packages/shared/src/hooks/log/useLogOpportunityNudgeImpression.ts b/packages/shared/src/hooks/log/useLogOpportunityNudgeImpression.ts
index d1b87d74432..33ae22ef34b 100644
--- a/packages/shared/src/hooks/log/useLogOpportunityNudgeImpression.ts
+++ b/packages/shared/src/hooks/log/useLogOpportunityNudgeImpression.ts
@@ -23,6 +23,10 @@ export const useLogOpportunityNudgeImpression = (
       return;
     }
 
+    if (!logRef.current) {
+      throw new Error('Log function is required to track opportunity nudges');
+    }
+
     logRef.current({
       event_name: LogEvent.ImpressionOpportunityNudge,
       target_id: targetId,
diff --git a/packages/shared/src/hooks/log/useLogSharedProps.ts b/packages/shared/src/hooks/log/useLogSharedProps.ts
index ef83b0985fe..300e132581f 100644
--- a/packages/shared/src/hooks/log/useLogSharedProps.ts
+++ b/packages/shared/src/hooks/log/useLogSharedProps.ts
@@ -14,7 +14,7 @@ export default function useLogSharedProps(
   deviceId: string,
 ): [MutableRefObject<Partial<LogEvent>>, boolean] {
   // Use ref instead of state to reduce renders
-  const sharedPropsRef = useRef<Partial<LogEvent>>();
+  const sharedPropsRef = useRef<Partial<LogEvent>>({});
   const { query } = useRouter();
   const { themeMode, spaciness, insaneMode } = useContext(SettingsContext);
   const { visit, anonymous, tokenRefreshed, user } = useContext(AuthContext);
diff --git a/packages/shared/src/hooks/onboarding/useGenerateUsername.ts b/packages/shared/src/hooks/onboarding/useGenerateUsername.ts
index 270f5794d6f..df259c4032e 100644
--- a/packages/shared/src/hooks/onboarding/useGenerateUsername.ts
+++ b/packages/shared/src/hooks/onboarding/useGenerateUsername.ts
@@ -17,6 +17,11 @@ export const useGenerateUsername = (
   const [username, setUsername] = useState('');
   const usernameRef = useRef(false);
   const { requestMethod } = useRequestProtocol();
+
+  if (!requestMethod) {
+    throw new Error('Request method is required in useGenerateUsername');
+  }
+
   const usernameQueryKey = ['generateUsername', name];
   const { data, isLoading } = useQuery<{
     generateUniqueUsername: string;
diff --git a/packages/shared/src/hooks/post/usePostActions.ts b/packages/shared/src/hooks/post/usePostActions.ts
index abb3586b7f3..4a9731bee5f 100644
--- a/packages/shared/src/hooks/post/usePostActions.ts
+++ b/packages/shared/src/hooks/post/usePostActions.ts
@@ -15,17 +15,24 @@ type UsePostActions = PostActionData & {
   onInteract: (interaction: PostActionData['interaction']) => void;
 };
 
-export const usePostActions = ({ post }: { post: Post }): UsePostActions => {
+const defaultPostActionData: PostActionData = {
+  interaction: 'none',
+  previousInteraction: 'none',
+};
+
+export const usePostActions = ({ post }: { post?: Post }): UsePostActions => {
   const client = useQueryClient();
+  const postId = post?.id;
   const key = useMemo(() => {
-    return generateQueryKey(RequestKey.PostActions, { id: post?.id });
-  }, [post?.id]);
+    if (!postId) {
+      return [RequestKey.PostActions, 'missing-post'];
+    }
+
+    return generateQueryKey(RequestKey.PostActions, { id: postId });
+  }, [postId]);
 
   const queryFn = useCallback((): PostActionData => {
-    return {
-      interaction: 'none',
-      previousInteraction: 'none',
-    };
+    return defaultPostActionData;
   }, []);
 
   const { data } = useQuery({
@@ -34,23 +41,31 @@ export const usePostActions = ({ post }: { post: Post }): UsePostActions => {
     initialData: queryFn,
     staleTime: Infinity,
     gcTime: Infinity,
+    enabled: !!postId,
     ...disabledRefetch,
   });
+  const actionData = data ?? queryFn();
 
   const onInteract = useCallback(
     (interaction: PostActionData['interaction']) => {
+      if (!postId) {
+        return;
+      }
+
       client.setQueryData<PostActionData>(key, {
         interaction,
         previousInteraction:
-          data?.interaction === interaction ? 'none' : data?.interaction,
+          actionData.interaction === interaction
+            ? 'none'
+            : actionData.interaction,
       });
     },
-    [client, key, data.interaction],
+    [client, key, actionData.interaction, postId],
   );
 
   return {
-    interaction: data?.interaction,
-    previousInteraction: data?.previousInteraction,
+    interaction: actionData.interaction,
+    previousInteraction: actionData.previousInteraction,
     onInteract,
   };
 };
diff --git a/packages/shared/src/hooks/profile/useProfileAchievements.ts b/packages/shared/src/hooks/profile/useProfileAchievements.ts
index 06549f96541..6f13871f177 100644
--- a/packages/shared/src/hooks/profile/useProfileAchievements.ts
+++ b/packages/shared/src/hooks/profile/useProfileAchievements.ts
@@ -18,7 +18,7 @@ export function useProfileAchievements(
 ): UseProfileAchievementsResult {
   const queryKey = generateQueryKey(
     RequestKey.UserAchievements,
-    user,
+    user ?? undefined,
     'profile',
   );
 
diff --git a/packages/shared/src/hooks/profile/useShowcaseAchievements.ts b/packages/shared/src/hooks/profile/useShowcaseAchievements.ts
index 46939099b40..ca748072259 100644
--- a/packages/shared/src/hooks/profile/useShowcaseAchievements.ts
+++ b/packages/shared/src/hooks/profile/useShowcaseAchievements.ts
@@ -21,7 +21,7 @@ export function useShowcaseAchievements(
 
   const queryKey = generateQueryKey(
     RequestKey.ShowcaseAchievements,
-    user,
+    user ?? undefined,
     'profile',
   );
 
diff --git a/packages/shared/src/hooks/referral/useJoinReferral.ts b/packages/shared/src/hooks/referral/useJoinReferral.ts
index 9f491256f1f..1b45df4de27 100644
--- a/packages/shared/src/hooks/referral/useJoinReferral.ts
+++ b/packages/shared/src/hooks/referral/useJoinReferral.ts
@@ -33,6 +33,10 @@ export const useJoinReferral = (): void => {
           id: referringUserId,
         });
 
+        if (!refetchBoot) {
+          throw new Error('Missing refetchBoot after setting join referral');
+        }
+
         refetchBoot();
       } catch (error) {
         if (
diff --git a/packages/shared/src/hooks/search/useSearchProviderSuggestions.ts b/packages/shared/src/hooks/search/useSearchProviderSuggestions.ts
index c86fad15f31..70f6529d310 100644
--- a/packages/shared/src/hooks/search/useSearchProviderSuggestions.ts
+++ b/packages/shared/src/hooks/search/useSearchProviderSuggestions.ts
@@ -96,9 +96,9 @@ export const useSearchProviderSuggestions = ({
         mutationVariables as Parameters<ContentPreferenceMutation>[0];
 
       const nextStatus = mutationKeyToContentPreferenceStatusMap[requestKey];
-      mutationQueryClient.setQueryData<SearchSuggestionResult | undefined>(
+      mutationQueryClient.setQueryData(
         queryKey,
-        (subData) => {
+        (subData: SearchSuggestionResult | undefined) => {
           if (!subData) {
             return subData;
           }
@@ -110,17 +110,17 @@ export const useSearchProviderSuggestions = ({
                 return {
                   ...hit,
                   contentPreference: nextStatus
-                    ? {
+                    ? ({
                         ...hit.contentPreference,
                         status: nextStatus,
-                      }
+                      } as typeof hit.contentPreference)
                     : undefined,
                 };
               }
 
               return hit;
             }),
-          };
+          } as SearchSuggestionResult;
         },
       );
     },
diff --git a/packages/shared/src/hooks/source/usePrivateSourceJoin.ts b/packages/shared/src/hooks/source/usePrivateSourceJoin.ts
index 5ab342d195c..28366577afd 100644
--- a/packages/shared/src/hooks/source/usePrivateSourceJoin.ts
+++ b/packages/shared/src/hooks/source/usePrivateSourceJoin.ts
@@ -62,7 +62,9 @@ export const usePrivateSourceJoin = ({
 
     router.replace(
       getPathnameWithQuery(
-        `${webappUrl}${sourceTypeToPage[sourceType]}/${sourceId}/${squadJoinToken}`,
+        `${webappUrl}${
+          sourceTypeToPage[sourceType as SourceType]
+        }/${sourceId}/${squadJoinToken}`,
         searchParams,
       ),
     );
diff --git a/packages/shared/src/hooks/source/useSourceStack.ts b/packages/shared/src/hooks/source/useSourceStack.ts
index 49949a7e4e2..2cec99f6740 100644
--- a/packages/shared/src/hooks/source/useSourceStack.ts
+++ b/packages/shared/src/hooks/source/useSourceStack.ts
@@ -24,7 +24,11 @@ export function useSourceStack(squad: Squad | null) {
     ? verifyPermission(squad, SourcePermissionsEnum.Edit)
     : false;
 
-  const queryKey = generateQueryKey(RequestKey.SourceStack, null, squad?.id);
+  const queryKey = generateQueryKey(
+    RequestKey.SourceStack,
+    undefined,
+    squad?.id,
+  );
 
   const query = useQuery({
     queryKey,
diff --git a/packages/shared/src/hooks/source/useSources.ts b/packages/shared/src/hooks/source/useSources.ts
index be451e3a1a4..0aeb57fb1c3 100644
--- a/packages/shared/src/hooks/source/useSources.ts
+++ b/packages/shared/src/hooks/source/useSources.ts
@@ -61,7 +61,7 @@ export const useSources = <T extends Source | Squad>({
   const result = useInfiniteQuery({
     queryKey: generateQueryKey(
       RequestKey.Sources,
-      null,
+      undefined,
       featured,
       isPublic,
       categoryId,
diff --git a/packages/shared/src/hooks/useAutoComplete.ts b/packages/shared/src/hooks/useAutoComplete.ts
index c76e8ff678b..73df136b8ae 100644
--- a/packages/shared/src/hooks/useAutoComplete.ts
+++ b/packages/shared/src/hooks/useAutoComplete.ts
@@ -29,7 +29,9 @@ export function useAutoComplete(
           setSelectedItemIndex(event.key === 'ArrowDown' ? 0 : n - 1);
         }
       } else if (event.key === 'Enter') {
-        submitQuery(selectedItemIndex > -1 && items[selectedItemIndex]);
+        submitQuery(
+          (selectedItemIndex > -1 && items[selectedItemIndex]) || undefined,
+        );
       }
     },
   };
diff --git a/packages/shared/src/hooks/useConditionalFeature.spec.tsx b/packages/shared/src/hooks/useConditionalFeature.spec.tsx
index eaf02b2de61..44afa7e84da 100644
--- a/packages/shared/src/hooks/useConditionalFeature.spec.tsx
+++ b/packages/shared/src/hooks/useConditionalFeature.spec.tsx
@@ -5,6 +5,7 @@ import { useConditionalFeature } from './useConditionalFeature';
 import { Feature } from '../lib/featureManagement';
 import loggedUser from '../../__tests__/fixture/loggedUser';
 import { AuthContextProvider } from '../contexts/AuthContext';
+import type { FeaturesReadyContextValue } from '../components/GrowthBookProvider';
 import {
   FeaturesReadyContext,
   GrowthBookProvider,
@@ -29,7 +30,9 @@ const createWrapper = ({ value = testFeature.defaultValue }) => {
         loadedUserFromCache
         squads={[]}
       >
-        <FeaturesReadyContext.Provider value={{ ready: !!value }}>
+        <FeaturesReadyContext.Provider
+          value={{ ready: !!value } as FeaturesReadyContextValue}
+        >
           <GrowthBookProvider
             app={BootApp.Test}
             user={loggedUser}
diff --git a/packages/shared/src/hooks/useConditionalFeature.ts b/packages/shared/src/hooks/useConditionalFeature.ts
index f3850c77c3e..fc8141c14a0 100644
--- a/packages/shared/src/hooks/useConditionalFeature.ts
+++ b/packages/shared/src/hooks/useConditionalFeature.ts
@@ -23,7 +23,8 @@ export const useConditionalFeature = <T extends JSONValue>({
 
   if (!isPending) {
     value = growthbook
-      ? growthbook.getFeatureValue(feature.id, feature.defaultValue)
+      ? growthbook.getFeatureValue(feature.id, feature.defaultValue) ??
+        (feature.defaultValue as WidenPrimitives<T>)
       : value;
   }
 
diff --git a/packages/shared/src/hooks/useCookieConsent.ts b/packages/shared/src/hooks/useCookieConsent.ts
index d757d4e25d5..bf78dc58c5a 100644
--- a/packages/shared/src/hooks/useCookieConsent.ts
+++ b/packages/shared/src/hooks/useCookieConsent.ts
@@ -25,7 +25,7 @@ const setBrowserCookie = (key: string): void => {
 
   const cookies = getCookies([key]);
 
-  if (cookies[key]) {
+  if (cookies?.[key]) {
     return;
   }
 
diff --git a/packages/shared/src/hooks/useDomPurify.ts b/packages/shared/src/hooks/useDomPurify.ts
index da83d6d4cdf..25b7023cf2a 100644
--- a/packages/shared/src/hooks/useDomPurify.ts
+++ b/packages/shared/src/hooks/useDomPurify.ts
@@ -2,7 +2,9 @@ import { useEffect, useState, useMemo } from 'react';
 import createDOMPurify from 'dompurify';
 
 export const useDomPurify = (): DOMPurify.DOMPurifyI => {
-  const [purify, setPurify] = useState<DOMPurify.DOMPurifyI>();
+  const [purify, setPurify] = useState<DOMPurify.DOMPurifyI>(
+    undefined as unknown as DOMPurify.DOMPurifyI,
+  );
 
   useEffect(() => {
     setPurify(createDOMPurify(globalThis.window));
diff --git a/packages/shared/src/hooks/useFeedLayout.ts b/packages/shared/src/hooks/useFeedLayout.ts
index cde35d1e931..ad3c871e9d6 100644
--- a/packages/shared/src/hooks/useFeedLayout.ts
+++ b/packages/shared/src/hooks/useFeedLayout.ts
@@ -129,7 +129,9 @@ export const useFeedLayout = ({
     feedName as UserProfileFeedType,
   );
 
-  const isFeedIncludedInListLayout = FeedLayoutMobileFeedPages.has(feedName);
+  const isFeedIncludedInListLayout = FeedLayoutMobileFeedPages.has(
+    feedName as OtherFeedPage,
+  );
 
   const shouldUseListFeedLayoutOnMobileTablet =
     !isLaptop && isFeedIncludedInListLayout;
diff --git a/packages/shared/src/hooks/useGif.ts b/packages/shared/src/hooks/useGif.ts
index 57543ad1c41..3bb5a38402e 100644
--- a/packages/shared/src/hooks/useGif.ts
+++ b/packages/shared/src/hooks/useGif.ts
@@ -42,7 +42,7 @@ const useGif = ({
         const params = new URLSearchParams({
           q: query,
           limit: limit.toString(),
-          ...(pageParam && { pos: pageParam as string }),
+          ...(pageParam ? { pos: pageParam as string } : {}),
         });
 
         const response = await fetch(`${apiUrl}/gifs?${params}`, {
diff --git a/packages/shared/src/hooks/useHostPermissionStatus.ts b/packages/shared/src/hooks/useHostPermissionStatus.ts
index 2fbe058e190..ca34023b53a 100644
--- a/packages/shared/src/hooks/useHostPermissionStatus.ts
+++ b/packages/shared/src/hooks/useHostPermissionStatus.ts
@@ -3,7 +3,7 @@ import { disabledRefetch } from '../lib/func';
 import { useExtensionContext } from '../contexts/ExtensionContext';
 import { generateQueryKey, RequestKey } from '../lib/query';
 
-export const hostKey = generateQueryKey(RequestKey.Host, null);
+export const hostKey = generateQueryKey(RequestKey.Host, undefined);
 
 export type UseHostStatus = {
   hostGranted: boolean;
diff --git a/packages/shared/src/hooks/useIOSError.ts b/packages/shared/src/hooks/useIOSError.ts
index 182a44a087d..8b722c1e0e8 100644
--- a/packages/shared/src/hooks/useIOSError.ts
+++ b/packages/shared/src/hooks/useIOSError.ts
@@ -27,7 +27,11 @@ export const useIOSError = (): void => {
     );
 
     return () => {
-      globalThis?.eventControllers?.[eventName]?.abort();
+      (
+        globalThis as typeof globalThis & {
+          eventControllers?: Partial<Record<string, AbortController>>;
+        }
+      ).eventControllers?.[eventName]?.abort();
     };
   }, [displayToast]);
 };
diff --git a/packages/shared/src/hooks/useLanguage.ts b/packages/shared/src/hooks/useLanguage.ts
index 5b9be093965..01557b03788 100644
--- a/packages/shared/src/hooks/useLanguage.ts
+++ b/packages/shared/src/hooks/useLanguage.ts
@@ -21,6 +21,10 @@ export const useLanguage = (): UseLanguage => {
 
   const { mutate: onLanguageChange } = useMutation({
     mutationFn: async (value?: string) => {
+      if (!user) {
+        throw new Error('Cannot update language without an authenticated user');
+      }
+
       await updateUser({
         ...user,
         language: value,
diff --git a/packages/shared/src/hooks/useLazyModal.ts b/packages/shared/src/hooks/useLazyModal.ts
index 8a7c74b142c..51f6a80a2b5 100644
--- a/packages/shared/src/hooks/useLazyModal.ts
+++ b/packages/shared/src/hooks/useLazyModal.ts
@@ -41,7 +41,7 @@ export function useLazyModal<
     () => ({
       openModal,
       closeModal,
-      modal,
+      modal: modal as T,
     }),
     [openModal, closeModal, modal],
   );
diff --git a/packages/shared/src/hooks/useMedia.ts b/packages/shared/src/hooks/useMedia.ts
index 804efd4c118..fcd4aaf79c5 100644
--- a/packages/shared/src/hooks/useMedia.ts
+++ b/packages/shared/src/hooks/useMedia.ts
@@ -17,7 +17,7 @@ export default function useMedia<T>(
 
   const [value, setValue] = useState<T>(() => {
     if (afterHydration) {
-      return undefined;
+      return undefined as T;
     }
 
     return typeof window !== 'undefined' ? getValue(getMedia()) : ssrValue;
diff --git a/packages/shared/src/hooks/usePopupSelector.ts b/packages/shared/src/hooks/usePopupSelector.ts
index 3747fef1c42..62ec2d254aa 100644
--- a/packages/shared/src/hooks/usePopupSelector.ts
+++ b/packages/shared/src/hooks/usePopupSelector.ts
@@ -3,6 +3,13 @@ import { useQueryClient } from '@tanstack/react-query';
 import { generateStorageKey, StorageTopic } from '../lib/storage';
 
 const POPUP_SELECTOR_KEY = [generateStorageKey(StorageTopic.Popup, 'selector')];
+const getDefaultParentSelector = (): HTMLElement => {
+  if (typeof document === 'undefined') {
+    throw new Error('Popup parent selector is unavailable on the server');
+  }
+
+  return document.body;
+};
 
 type AppendFn = () => HTMLElement;
 
@@ -35,7 +42,7 @@ export const usePopupSelector = ({
 
   return {
     parentSelector: useMemo(
-      () => parentSelector ?? propSelector,
+      () => parentSelector ?? propSelector ?? getDefaultParentSelector,
       [parentSelector, propSelector],
     ),
     onAppendTooltipTo: useCallback(
diff --git a/packages/shared/src/hooks/usePostContent.ts b/packages/shared/src/hooks/usePostContent.ts
index 4dc34f42f82..b1e9fb47e6b 100644
--- a/packages/shared/src/hooks/usePostContent.ts
+++ b/packages/shared/src/hooks/usePostContent.ts
@@ -95,7 +95,7 @@ const usePostContent = ({
     },
   );
 
-  const loggedPostEvent = useRef(null);
+  const loggedPostEvent = useRef<string | null>(null);
 
   useEffect(() => {
     if (!post) {
diff --git a/packages/shared/src/hooks/usePrevious.ts b/packages/shared/src/hooks/usePrevious.ts
index 71063f03cf5..5cdb9e9d9dc 100644
--- a/packages/shared/src/hooks/usePrevious.ts
+++ b/packages/shared/src/hooks/usePrevious.ts
@@ -1,6 +1,6 @@
 import React, { useEffect } from 'react';
 
-export const usePrevious = <T>(value: T): T => {
+export const usePrevious = <T>(value: T): T | undefined => {
   const ref = React.useRef<T>();
   useEffect(() => {
     ref.current = value;
diff --git a/packages/shared/src/hooks/usePrivilegedSession.ts b/packages/shared/src/hooks/usePrivilegedSession.ts
index 0c66bf2ee3a..bba697f1fc6 100644
--- a/packages/shared/src/hooks/usePrivilegedSession.ts
+++ b/packages/shared/src/hooks/usePrivilegedSession.ts
@@ -39,7 +39,7 @@ const usePrivilegedSession = ({
       const onVerified = () => {
         if (onVerification?.current) {
           onVerification.current();
-          onVerification.current = null;
+          onVerification.current = undefined;
         } else {
           displayToast('Session successfully verified!');
         }
diff --git a/packages/shared/src/hooks/useTagAndSource.ts b/packages/shared/src/hooks/useTagAndSource.ts
index bf311417d3a..fa6c7752be5 100644
--- a/packages/shared/src/hooks/useTagAndSource.ts
+++ b/packages/shared/src/hooks/useTagAndSource.ts
@@ -119,7 +119,7 @@ export default function useTagAndSource({
         extra: JSON.stringify({ origin, feed_id: feedId }),
       });
       if (alerts?.filter && user && shouldUpdateAlerts) {
-        updateAlerts({ filter: false, myFeed: 'created' });
+        updateAlerts?.({ filter: false, myFeed: 'created' });
       }
       await followTags({ tags });
 
diff --git a/packages/shared/src/hooks/userCompany/useUserCompaniesQuery.tsx b/packages/shared/src/hooks/userCompany/useUserCompaniesQuery.tsx
index 138c75e2316..e41e01025d8 100644
--- a/packages/shared/src/hooks/userCompany/useUserCompaniesQuery.tsx
+++ b/packages/shared/src/hooks/userCompany/useUserCompaniesQuery.tsx
@@ -26,7 +26,7 @@ export const useUserCompaniesQuery = (): UseUserCompaniesQuery => {
   });
 
   return {
-    userCompanies: data,
+    userCompanies: data ?? [],
     isVerified: !isPending && !!data?.[0]?.company,
     isLoading: isPending,
   };