diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cc24903..10dae18 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -26,3 +26,4 @@ jobs:
           JWT_SECRET: "ci-placeholder-jwt-secret-min-32-chars"
           DATABASE_URL: "postgresql://placeholder:placeholder@localhost:5432/placeholder"
           DIRECT_URL: "postgresql://placeholder:placeholder@localhost:5432/placeholder"
+          ADMIN_PASSWORD: "ci-placeholder-admin-password"
diff --git a/.jules/sentinel.md b/.jules/sentinel.md
new file mode 100644
index 0000000..8dfad4d
--- /dev/null
+++ b/.jules/sentinel.md
@@ -0,0 +1,4 @@
+## 2025-06-03 - Avoid Hardcoded Passwords in Source Code
+**Vulnerability:** A hardcoded admin password was found directly embedded in the source code (`packages/web/src/lib/server/admin-auth.ts`).
+**Learning:** Hardcoded secrets (passwords, API keys, tokens) in source code pose a critical security risk as they can be easily extracted by anyone with access to the codebase or the compiled artifacts. In this project, even static authentication constants like `ADMIN_PASSWORD` should be securely managed through environment variables to ensure secrets never reach the repository.
+**Prevention:** Always use `process.env` (or a validated schema like Zod's `env`) to read secrets. Ensure all required secrets are documented in `.env.example` and that CI pipelines provide placeholder values when these variables are required for build time schemas.
diff --git a/packages/web/.env.example b/packages/web/.env.example
index e99d51e..73368e6 100644
--- a/packages/web/.env.example
+++ b/packages/web/.env.example
@@ -4,3 +4,4 @@ AUTH_SECRET=replace-with-min-32-char-random-string
 DATABASE_URL="postgresql://postgres.[project]:[password]@aws-0-ap-northeast-1.pooler.supabase.com:6543/postgres?pgbouncer=true"
 DIRECT_URL="postgresql://postgres.[project]:[password]@db.uwxfseowdzuuepeeudrx.supabase.co:5432/postgres"
 JWT_SECRET="replace-with-32-char-minimum-random-string"
+ADMIN_PASSWORD=replace-with-secure-admin-password
diff --git a/packages/web/src/lib/server/admin-auth.ts b/packages/web/src/lib/server/admin-auth.ts
index 5390fa4..6610d00 100644
--- a/packages/web/src/lib/server/admin-auth.ts
+++ b/packages/web/src/lib/server/admin-auth.ts
@@ -1,19 +1,27 @@
 import 'server-only'
 
-import { createHmac, randomBytes, timingSafeEqual } from 'crypto'
+import { createHmac, pbkdf2Sync, randomBytes, timingSafeEqual } from 'crypto'
 import { cookies } from 'next/headers'
 import { NextRequest, NextResponse } from 'next/server'
 
 import { env } from './env'
 
 export const ADMIN_USERNAME = 'admin'
-export const ADMIN_PASSWORD = 'og9oRajx7h88v1RIj3eDgdrh9jgLYVV3'
 
 const ADMIN_SESSION_COOKIE = 'argos_admin_session'
 const ADMIN_SESSION_TTL_MS = 12 * 60 * 60 * 1000
 const ADMIN_IMPERSONATION_TTL_MS = 60 * 1000
 const ADMIN_IMPERSONATION_PREFIX = 'argos_imp'
 
+// Pre-compute the target hash at module initialization to avoid synchronous work in the request path
+const ADMIN_PASSWORD_HASH = pbkdf2Sync(env.ADMIN_PASSWORD, env.JWT_SECRET, 1000, 64, 'sha512')
+const ADMIN_USERNAME_HASH = pbkdf2Sync(ADMIN_USERNAME, env.JWT_SECRET, 1000, 64, 'sha512')
+
+function safeEqualHash(input: string, targetHash: Buffer): boolean {
+  const inputHash = pbkdf2Sync(input, env.JWT_SECRET, 1000, 64, 'sha512')
+  return timingSafeEqual(inputHash, targetHash)
+}
+
 function safeEqual(a: string, b: string): boolean {
   const aHash = createHmac('sha256', env.JWT_SECRET).update(a).digest()
   const bHash = createHmac('sha256', env.JWT_SECRET).update(b).digest()
@@ -29,8 +37,8 @@ export function verifyAdminCredentials(input: {
   password: string
 }): boolean {
   return (
-    safeEqual(input.username, ADMIN_USERNAME) &&
-    safeEqual(input.password, ADMIN_PASSWORD)
+    safeEqualHash(input.username, ADMIN_USERNAME_HASH) &&
+    safeEqualHash(input.password, ADMIN_PASSWORD_HASH)
   )
 }
 
diff --git a/packages/web/src/lib/server/env.ts b/packages/web/src/lib/server/env.ts
index 86ed9a3..872eee1 100644
--- a/packages/web/src/lib/server/env.ts
+++ b/packages/web/src/lib/server/env.ts
@@ -5,6 +5,7 @@ const EnvSchema = z.object({
   DATABASE_URL: z.string().min(1),
   DIRECT_URL: z.string().min(1),
   JWT_SECRET: z.string().min(32),
+  ADMIN_PASSWORD: z.string().trim().min(8),
 })
 
 export const env = EnvSchema.parse(process.env)