From 8de09d8e4d88077516cbf865a318de4569070b8a Mon Sep 17 00:00:00 2001
From: arthurlw <arthur.l.wigo@gmail.com>
Date: Tue, 2 Dec 2025 10:23:46 -0800
Subject: [PATCH 1/2] Implement dependency injection for file paths

---
 go.mod                             |  3 ++-
 go.sum                             |  4 ++++
 internal/cli/root.go               |  4 ++--
 internal/fsutil/fsutil.go          | 17 ++++++++++-------
 internal/git/git.go                |  3 ++-
 internal/nodepkg/nodepkg.go        |  8 +++++---
 internal/stacks/express/express.go | 14 +++++++-------
 internal/stacks/mongodb/mongodb.go | 12 ++++++------
 internal/stacks/nextjs/nextjs.go   | 12 ++++++------
 9 files changed, 44 insertions(+), 33 deletions(-)

diff --git a/go.mod b/go.mod
index 7b03e1c..4dfbddb 100644
--- a/go.mod
+++ b/go.mod
@@ -14,6 +14,7 @@ require (
 	github.com/golang/snappy v0.0.4 // indirect
 	github.com/klauspost/compress v1.16.7 // indirect
 	github.com/montanaflynn/stats v0.7.1 // indirect
+	github.com/spf13/afero v1.15.0 // indirect
 	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
 	github.com/xdg-go/scram v1.1.2 // indirect
 	github.com/xdg-go/stringprep v1.0.4 // indirect
@@ -35,5 +36,5 @@ require (
 	golang.org/x/sync v0.17.0
 	golang.org/x/sys v0.23.0 // indirect
 	golang.org/x/term v0.23.0 // indirect
-	golang.org/x/text v0.17.0 // indirect
+	golang.org/x/text v0.28.0 // indirect
 )
diff --git a/go.sum b/go.sum
index 7a93120..ccaaac6 100644
--- a/go.sum
+++ b/go.sum
@@ -44,6 +44,8 @@ github.com/montanaflynn/stats v0.7.1/go.mod h1:etXPPgVO6n31NxCd9KQUMvCM+ve0ruNzt
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/spf13/afero v1.15.0 h1:b/YBCLWAJdFWJTN9cLhiXXcD7mzKn9Dm86dNnfyQw1I=
+github.com/spf13/afero v1.15.0/go.mod h1:NC2ByUVxtQs4b3sIUphxK0NioZnmxgyCrfzeuq8lxMg=
 github.com/spf13/cobra v1.10.1 h1:lJeBwCfmrnXthfAupyUTzJ/J4Nc1RsHC/mSRU2dll/s=
 github.com/spf13/cobra v1.10.1/go.mod h1:7SmJGaTHFVBY0jW4NXGluQoLvhqFQM+6XSKD+P4XaB0=
 github.com/spf13/pflag v1.0.9 h1:9exaQaMOCwffKiiiYk6/BndUBv+iRViNW+4lEMi0PvY=
@@ -98,6 +100,8 @@ golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
 golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/text v0.17.0 h1:XtiM5bkSOt+ewxlOE/aE/AKEHibwj/6gvWMl9Rsh0Qc=
 golang.org/x/text v0.17.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=
+golang.org/x/text v0.28.0 h1:rhazDwis8INMIwQ4tpjLDzUhx6RlXqZNPEM0huQojng=
+golang.org/x/text v0.28.0/go.mod h1:U8nCwOR8jO/marOQ0QbDiOngZVEBB7MAiitBuMjXiNU=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
diff --git a/internal/cli/root.go b/internal/cli/root.go
index 6d077f4..70d55a5 100644
--- a/internal/cli/root.go
+++ b/internal/cli/root.go
@@ -3,12 +3,12 @@ package cli
 import (
 	"context"
 	"fmt"
-	"os"
 	"strconv"
 	"strings"
 	"time"
 
 	"github.com/AlecAivazis/survey/v2"
+	"github.com/b-jonathan/taco/internal/fsutil"
 	"github.com/b-jonathan/taco/internal/gh"
 	"github.com/b-jonathan/taco/internal/git"
 	"github.com/b-jonathan/taco/internal/logx"
@@ -160,7 +160,7 @@ func initCmd() *cobra.Command {
 			}
 
 			projectRoot := params.Name
-			if err := os.MkdirAll(projectRoot, 0o755); err != nil {
+			if err := fsutil.Fs.MkdirAll(projectRoot, 0o755); err != nil {
 				return fmt.Errorf("mkdir project root: %w", err)
 			}
 
diff --git a/internal/fsutil/fsutil.go b/internal/fsutil/fsutil.go
index a90c476..6580109 100644
--- a/internal/fsutil/fsutil.go
+++ b/internal/fsutil/fsutil.go
@@ -11,16 +11,19 @@ import (
 	"text/template"
 
 	"github.com/b-jonathan/taco/internal/stacks/templates"
+	"github.com/spf13/afero"
 )
 
+var Fs = afero.NewOsFs()
+
 // TODO: Some of these were completely vibe coded, just need to refactor a bit to make more consistent
 func EnsureFile(path string) error {
 	// Create parent directories if needed.
-	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
+	if err := Fs.MkdirAll(filepath.Dir(path), 0o755); err != nil {
 		return err
 	}
 	// Create the file if missing. O_EXCL prevents clobbering if a race happens.
-	f, err := os.OpenFile(path, os.O_CREATE|os.O_EXCL, 0o644)
+	f, err := Fs.OpenFile(path, os.O_CREATE|os.O_EXCL, 0o644)
 	if err != nil {
 		// If it already exists, that’s fine.
 		if os.IsExist(err) {
@@ -39,7 +42,7 @@ func WriteFile(file FileInfo) error {
 	}
 	// log.Println("Ensuring file complete")
 	// log.Printf("Writing File: %s", path)
-	if err := os.WriteFile(file.Path, file.Content, 0o644); err != nil {
+	if err := afero.WriteFile(Fs, file.Path, file.Content, 0o644); err != nil {
 		return fmt.Errorf("write %s file: %w", filename, err)
 	}
 	// log.Println("Writing file complete")
@@ -56,7 +59,7 @@ func WriteMultipleFiles(files []FileInfo) error {
 }
 
 func AppendUniqueLines(path string, lines []string) error {
-	buf, _ := os.ReadFile(path)
+	buf, _ := afero.ReadFile(Fs, path)
 	for _, line := range lines {
 		if !bytes.Contains(buf, []byte(line+"\n")) && !bytes.Equal(bytes.TrimSpace(buf), []byte(line)) {
 			if len(buf) > 0 && buf[len(buf)-1] != '\n' {
@@ -65,7 +68,7 @@ func AppendUniqueLines(path string, lines []string) error {
 			buf = append(buf, []byte(line+"\n")...)
 		}
 	}
-	return os.WriteFile(path, buf, 0o644)
+	return afero.WriteFile(Fs, path, buf, 0o644)
 }
 
 // in a shared package or file
@@ -161,10 +164,10 @@ func GenerateFromTemplateDir(templateRoot, outputRoot string) error {
 			return fmt.Errorf("render template %s: %w", path, err)
 		}
 
-		if err := os.MkdirAll(filepath.Dir(finalPath), 0755); err != nil {
+		if err := Fs.MkdirAll(filepath.Dir(finalPath), 0755); err != nil {
 			return err
 		}
 
-		return os.WriteFile(finalPath, content, 0644)
+		return afero.WriteFile(Fs, finalPath, content, 0644)
 	})
 }
diff --git a/internal/git/git.go b/internal/git/git.go
index 5282eac..2c61787 100644
--- a/internal/git/git.go
+++ b/internal/git/git.go
@@ -7,6 +7,7 @@ import (
 	"path/filepath"
 
 	"github.com/b-jonathan/taco/internal/execx"
+	"github.com/b-jonathan/taco/internal/fsutil"
 )
 
 // TODO: There is absolutely no reason for init and push to be in one function, gonna have to refactor this for sure
@@ -14,7 +15,7 @@ import (
 func Init(ctx context.Context, projectRoot string) error {
 
 	// If already a repo, skip init
-	if _, err := os.Stat(filepath.Join(projectRoot, ".git")); os.IsNotExist(err) {
+	if _, err := fsutil.Fs.Stat(filepath.Join(projectRoot, ".git")); os.IsNotExist(err) {
 		if err := execx.RunCmd(ctx, projectRoot, "git init"); err != nil {
 			return fmt.Errorf("git init: %w", err)
 		}
diff --git a/internal/nodepkg/nodepkg.go b/internal/nodepkg/nodepkg.go
index 098f96b..dc493d1 100644
--- a/internal/nodepkg/nodepkg.go
+++ b/internal/nodepkg/nodepkg.go
@@ -2,13 +2,15 @@ package nodepkg
 
 import (
 	"encoding/json"
-	"os"
 	"path/filepath"
+
+	"github.com/b-jonathan/taco/internal/fsutil"
+	"github.com/spf13/afero"
 )
 
 func InitPackage(dir string, params InitPackageParams) error {
 	path := filepath.Join(dir, "package.json")
-	b, err := os.ReadFile(path)
+	b, err := afero.ReadFile(fsutil.Fs, path)
 	if err != nil {
 		return err
 	}
@@ -42,5 +44,5 @@ func InitPackage(dir string, params InitPackageParams) error {
 	if err != nil {
 		return err
 	}
-	return os.WriteFile(path, out, 0o644)
+	return afero.WriteFile(fsutil.Fs, path, out, 0o644)
 }
diff --git a/internal/stacks/express/express.go b/internal/stacks/express/express.go
index 045eb7f..f92f759 100644
--- a/internal/stacks/express/express.go
+++ b/internal/stacks/express/express.go
@@ -3,12 +3,12 @@ package express
 import (
 	"context"
 	"fmt"
-	"os"
 	"path/filepath"
 	"strings"
 
 	"github.com/b-jonathan/taco/internal/execx"
 	"github.com/b-jonathan/taco/internal/fsutil"
+	"github.com/spf13/afero"
 
 	"github.com/b-jonathan/taco/internal/stacks"
 )
@@ -27,7 +27,7 @@ func (express) Init(ctx context.Context, opts *Options) error {
 	backendDir := filepath.Join(opts.ProjectRoot, "backend")
 	srcDir := filepath.Join(backendDir, "src")
 
-	if err := os.MkdirAll(srcDir, 0o755); err != nil {
+	if err := fsutil.Fs.MkdirAll(srcDir, 0o755); err != nil {
 		return fmt.Errorf("mkdir: %w", err)
 	}
 
@@ -85,14 +85,14 @@ func (express) Post(ctx context.Context, opts *Options) error {
 		[]string{"backend/node_modules/", "backend/dist/", "backend/.env*"})
 	path := filepath.Join(opts.ProjectRoot, "backend", ".env")
 	dir := filepath.Dir(path)
-	if err := os.MkdirAll(dir, 0o755); err != nil {
+	if err := fsutil.Fs.MkdirAll(dir, 0o755); err != nil {
 		return fmt.Errorf("mkdir %s: %w", dir, err)
 	}
 	content := `
-		PORT=4000
-		FRONTEND_ORIGIN=http://localhost:3000
-		`
-	if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
+        PORT=4000
+        FRONTEND_ORIGIN=http://localhost:3000
+        `
+	if err := afero.WriteFile(fsutil.Fs, path, []byte(content), 0o644); err != nil {
 		return fmt.Errorf("write %s: %w", path, err)
 	}
 	return nil
diff --git a/internal/stacks/mongodb/mongodb.go b/internal/stacks/mongodb/mongodb.go
index f3f0f1e..a301037 100644
--- a/internal/stacks/mongodb/mongodb.go
+++ b/internal/stacks/mongodb/mongodb.go
@@ -3,7 +3,6 @@ package mongodb
 import (
 	"context"
 	"fmt"
-	"os"
 	"path/filepath"
 	"strings"
 	"time"
@@ -13,6 +12,7 @@ import (
 	"github.com/b-jonathan/taco/internal/fsutil"
 	"github.com/b-jonathan/taco/internal/prompt"
 	"github.com/b-jonathan/taco/internal/stacks"
+	"github.com/spf13/afero"
 	"go.mongodb.org/mongo-driver/mongo"
 	"go.mongodb.org/mongo-driver/mongo/options"
 )
@@ -150,7 +150,7 @@ func (mongodb) Generate(ctx context.Context, opts *Options) error {
 	}
 
 	indexPath := filepath.Join(backendDir, "src", "index.ts")
-	indexBytes, err := os.ReadFile(indexPath)
+	indexBytes, err := afero.ReadFile(fsutil.Fs, indexPath)
 	if err != nil {
 		return fmt.Errorf("read index.ts: %w", err)
 	}
@@ -181,19 +181,19 @@ import { connectDB } from "./db/client";`, 1)
 func (mongodb) Post(ctx context.Context, opts *Options) error {
 	// gitignorePath := filepath.Join(opts.ProjectRoot, ".gitignore")
 	// if err := fsutil.EnsureFile(gitignorePath); err != nil {
-	// 	return fmt.Errorf("ensure gitignore file: %w", err)
+	//  return fmt.Errorf("ensure gitignore file: %w", err)
 	// }
 
 	// _ = fsutil.AppendUniqueLines(gitignorePath,
-	// 	[]string{"backend/node_modules/", "backend/dist/", "backend/.env*"})
+	//  []string{"backend/node_modules/", "backend/dist/", "backend/.env*"})
 	path := filepath.Join(opts.ProjectRoot, "backend", ".env")
 	// dir := filepath.Dir(path)
 	// if err := os.MkdirAll(dir, 0o755); err != nil {
-	// 	return fmt.Errorf("mkdir %s: %w", dir, err)
+	//  return fmt.Errorf("mkdir %s: %w", dir, err)
 	// }
 	// TODO: Make this not as scuffed lol
 	content := fmt.Sprintf(`
-	MONGODB_URI=%s/%s`, opts.DatabaseURI, opts.AppName)
+    MONGODB_URI=%s/%s`, opts.DatabaseURI, opts.AppName)
 	_ = fsutil.AppendUniqueLines(path, []string{content})
 	return nil
 }
diff --git a/internal/stacks/nextjs/nextjs.go b/internal/stacks/nextjs/nextjs.go
index ff14509..ab41456 100644
--- a/internal/stacks/nextjs/nextjs.go
+++ b/internal/stacks/nextjs/nextjs.go
@@ -3,7 +3,6 @@ package nextjs
 import (
 	"context"
 	"fmt"
-	"os"
 	"path/filepath"
 	"strings"
 
@@ -11,6 +10,7 @@ import (
 	"github.com/b-jonathan/taco/internal/fsutil"
 	"github.com/b-jonathan/taco/internal/nodepkg"
 	"github.com/b-jonathan/taco/internal/stacks"
+	"github.com/spf13/afero"
 )
 
 type Stack = stacks.Stack
@@ -25,7 +25,7 @@ func (nextjs) Type() string { return "frontend" }
 func (nextjs) Name() string { return "express" }
 
 func (nextjs) Init(ctx context.Context, opts *Options) error {
-	if err := os.MkdirAll(opts.ProjectRoot, 0o755); err != nil {
+	if err := fsutil.Fs.MkdirAll(opts.ProjectRoot, 0o755); err != nil {
 		return fmt.Errorf("mkdir: %w", err)
 	}
 	// 1) Scaffold Next.js in TS, without ESLint, noninteractive
@@ -105,12 +105,12 @@ func (nextjs) Post(ctx context.Context, opts *Options) error {
 	}
 
 	dir := filepath.Dir(envPath)
-	if err := os.MkdirAll(dir, 0o755); err != nil {
+	if err := fsutil.Fs.MkdirAll(dir, 0o755); err != nil {
 		return fmt.Errorf("mkdir %s: %w", dir, err)
 	}
-	content := `NEXT_PUBLIC_BACKEND_URL=http://localhost:4000	
-		`
-	if err := os.WriteFile(envPath, []byte(content), 0o644); err != nil {
+	content := `NEXT_PUBLIC_BACKEND_URL=http://localhost:4000
+        `
+	if err := afero.WriteFile(fsutil.Fs, envPath, []byte(content), 0o644); err != nil {
 		return fmt.Errorf("write %s: %w", envPath, err)
 	}
 

From 8022248e57b3799cb4ffa9079ddf43954827a5f6 Mon Sep 17 00:00:00 2001
From: "ribellye@gmail.com" <ribellye@gmail.com>
Date: Mon, 2 Feb 2026 21:13:05 -0800
Subject: [PATCH 2/2] minor fixes

---
 .github/PULL_REQUEST_TEMPLATE.md              | 39 ++-----------------
 internal/cli/root.go                          |  4 +-
 internal/fsutil/fsutil.go                     | 13 ++++---
 internal/prompt/prompt.go                     |  4 +-
 internal/stacks/express/express.go            | 26 +++++++++++--
 internal/stacks/firebase/firebase.go          |  2 +-
 internal/stacks/mongodb/mongodb.go            |  7 ++--
 internal/stacks/nextjs/nextjs.go              | 10 ++---
 .../templates/express/src/index.ts.tmpl       |  2 +-
 9 files changed, 48 insertions(+), 59 deletions(-)

diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index 05e33a4..1f7d6bc 100644
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -1,38 +1,5 @@
-## Summary
+- [ ] Closes #(issue number) if applicable.
+- [ ] Passes all code checks
+- [ ] Added new tests
 
 Describe the purpose of this pull request. What does it do, and why is it needed?
-
-Closes #(issue number) if applicable.
-
----
-
-## Changes Made
-
-- [ ] Added new stack: `<stack name>`
-- [ ] Updated existing functionality
-- [ ] Improved documentation
-- [ ] Refactored internal code
-- [ ] Fixed a bug
-
-Briefly summarize the major changes:
-
--  
--  
--
-
----
-
-## Testing
-
-How was this change tested?
-
-- [ ] `go test ./...` passes locally
-- [ ] Manual testing done with `taco` CLI
-- [ ] CI checks pass
-
-Provide details:
-
-```bash
-# Example test commands
-go test ./...
-taco init test-app
diff --git a/internal/cli/root.go b/internal/cli/root.go
index 70d55a5..6e30a1d 100644
--- a/internal/cli/root.go
+++ b/internal/cli/root.go
@@ -197,6 +197,8 @@ func initCmd() *cobra.Command {
 				ProjectRoot: projectRoot,
 				AppName:     params.Name,
 				Frontend:    stack["frontend"],
+				Backend:     stack["backend"],
+				Database:    stack["database"],
 				FrontendURL: "http://localhost:3000",
 				BackendURL:  "http://localhost:4000",
 				Port:        4000,
@@ -275,7 +277,7 @@ func initCmd() *cobra.Command {
 					return fmt.Errorf("create repo: %w", err)
 				}
 
-				fmt.Println(cmd.OutOrStdout(), "Created:", repo.GetHTMLURL())
+				fmt.Println("Created:", repo.GetHTMLURL())
 				remoteURL := repo.GetSSHURL()
 				if params.Remote == "https" {
 					remoteURL = repo.GetCloneURL()
diff --git a/internal/fsutil/fsutil.go b/internal/fsutil/fsutil.go
index 6580109..b7e2aa0 100644
--- a/internal/fsutil/fsutil.go
+++ b/internal/fsutil/fsutil.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io/fs"
 	"os"
+	"path"
 	"path/filepath"
 	"strings"
 	"sync"
@@ -106,11 +107,13 @@ func ValidateDependency(stack, dependency string) bool {
 	if stack == "none" || dependency == "none" {
 		return true
 	}
-	stackPath := filepath.Join("internal", "stacks", "templates", stack)
+	if stack == "" || dependency == "" {
+		return false
+	}
 
-	info, err := os.ReadDir(stackPath)
+	info, err := templates.FS.ReadDir(stack)
 	if err != nil {
-		fmt.Printf("path does not exist %s\n", stackPath)
+		fmt.Printf("embedded path does not exist %s\n", stack)
 		return false
 	}
 	//check if subfolder is "src", "db" or doesn't exist -> true.
@@ -129,8 +132,8 @@ func ValidateDependency(stack, dependency string) bool {
 		return true
 	}
 	//else, check if dependency is in subfolders of stack.
-	dependencyPath := filepath.Join(stackPath, dependency)
-	if info, err := os.Stat(dependencyPath); err == nil && info.IsDir() {
+	dependencyPath := path.Join(stack, dependency)
+	if _, err := templates.FS.ReadDir(dependencyPath); err == nil {
 		return true
 	}
 	return false
diff --git a/internal/prompt/prompt.go b/internal/prompt/prompt.go
index a0cdd4d..3d9bdfe 100644
--- a/internal/prompt/prompt.go
+++ b/internal/prompt/prompt.go
@@ -71,14 +71,14 @@ func CreateSurveyMultiSelect(message string, choices []string, options AskOpts)
 		return nil, fmt.Errorf("options cannot be empty")
 	}
 
-	prompt := &survey.Select{
+	prompt := &survey.MultiSelect{
 		Message:  message,
 		Options:  choices, //choices, this is a bit weird AHHAHA
 		Help:     options.Help,
 		PageSize: options.PageSize,
 	}
 
-	if v, ok := options.Default.(string); ok {
+	if v, ok := options.Default.([]string); ok {
 		prompt.Default = v
 	}
 	return askManyString(prompt, options)
diff --git a/internal/stacks/express/express.go b/internal/stacks/express/express.go
index f92f759..40ba0c7 100644
--- a/internal/stacks/express/express.go
+++ b/internal/stacks/express/express.go
@@ -8,6 +8,7 @@ import (
 
 	"github.com/b-jonathan/taco/internal/execx"
 	"github.com/b-jonathan/taco/internal/fsutil"
+	"github.com/b-jonathan/taco/internal/nodepkg"
 	"github.com/spf13/afero"
 
 	"github.com/b-jonathan/taco/internal/stacks"
@@ -55,6 +56,7 @@ func (express) Init(ctx context.Context, opts *Options) error {
 		"eslint-plugin-n",
 		"eslint-config-prettier",
 		"prettier",
+		"tsx",
 	}
 	//TODO: Prob can Refactor this somewhere, like keeping track of depencies to be installed, not urgent tho
 	if err := execx.RunCmd(ctx, backendDir, "npm install -D "+strings.Join(devDependencies, " ")); err != nil {
@@ -88,12 +90,28 @@ func (express) Post(ctx context.Context, opts *Options) error {
 	if err := fsutil.Fs.MkdirAll(dir, 0o755); err != nil {
 		return fmt.Errorf("mkdir %s: %w", dir, err)
 	}
-	content := `
-        PORT=4000
-        FRONTEND_ORIGIN=http://localhost:3000
-        `
+	content := `PORT=4000
+FRONTEND_ORIGIN=http://localhost:3000`
 	if err := afero.WriteFile(fsutil.Fs, path, []byte(content), 0o644); err != nil {
 		return fmt.Errorf("write %s: %w", path, err)
 	}
+
+	params := nodepkg.InitPackageParams{
+		Name: "backend",
+		Main: "src/index.ts",
+		Scripts: map[string]string{
+			"build":      "tsc -p tsconfig.json",
+			"dev":        "tsx watch src/index.ts",
+			"lint-check": "eslint . && prettier --check .",
+			"lint-fix":   "eslint . --fix && prettier --write .",
+			"start":      "node dist/index.js",
+			"test":       "echo \"Error: no test specified\" && exit 1",
+		},
+	}
+	backendDir := filepath.Join(opts.ProjectRoot, "backend")
+	if err := nodepkg.InitPackage(backendDir, params); err != nil {
+		return fmt.Errorf("init express package.json: %w", err)
+	}
+
 	return nil
 }
diff --git a/internal/stacks/firebase/firebase.go b/internal/stacks/firebase/firebase.go
index 70cdb24..44b3946 100644
--- a/internal/stacks/firebase/firebase.go
+++ b/internal/stacks/firebase/firebase.go
@@ -141,7 +141,7 @@ func (firebase) Generate(ctx context.Context, opts *Options) error {
 	}
 
 	templateDir := "firebase/nextjs"
-	outputDir := filepath.Join(frontendDir, "src")
+	outputDir := filepath.Join(frontendDir)
 
 	if err := fsutil.GenerateFromTemplateDir(templateDir, outputDir); err != nil {
 		return fmt.Errorf("generate firebase nextjs templates: %w", err)
diff --git a/internal/stacks/mongodb/mongodb.go b/internal/stacks/mongodb/mongodb.go
index a301037..8a53fa1 100644
--- a/internal/stacks/mongodb/mongodb.go
+++ b/internal/stacks/mongodb/mongodb.go
@@ -134,7 +134,9 @@ func (mongodb) Init(ctx context.Context, opts *Options) error {
 
 func (mongodb) Generate(ctx context.Context, opts *Options) error {
 	backendDir := filepath.Join(opts.ProjectRoot, "backend")
-
+	if !fsutil.ValidateDependency("mongodb", opts.Backend) {
+		return fmt.Errorf("mongodb cannot be used with backend '%s'", opts.Backend)
+	}
 	if err := execx.RunCmd(ctx, backendDir, "npm install mongodb"); err != nil {
 		return fmt.Errorf("npm install mongodb: %w", err)
 	}
@@ -192,8 +194,7 @@ func (mongodb) Post(ctx context.Context, opts *Options) error {
 	//  return fmt.Errorf("mkdir %s: %w", dir, err)
 	// }
 	// TODO: Make this not as scuffed lol
-	content := fmt.Sprintf(`
-    MONGODB_URI=%s/%s`, opts.DatabaseURI, opts.AppName)
+	content := fmt.Sprintf(`MONGODB_URI=%s/%s`, opts.DatabaseURI, opts.AppName)
 	_ = fsutil.AppendUniqueLines(path, []string{content})
 	return nil
 }
diff --git a/internal/stacks/nextjs/nextjs.go b/internal/stacks/nextjs/nextjs.go
index ab41456..9aafb79 100644
--- a/internal/stacks/nextjs/nextjs.go
+++ b/internal/stacks/nextjs/nextjs.go
@@ -22,7 +22,7 @@ func New() Stack { return &nextjs{} }
 
 func (nextjs) Type() string { return "frontend" }
 
-func (nextjs) Name() string { return "express" }
+func (nextjs) Name() string { return "nextjs" }
 
 func (nextjs) Init(ctx context.Context, opts *Options) error {
 	if err := fsutil.Fs.MkdirAll(opts.ProjectRoot, 0o755); err != nil {
@@ -81,15 +81,14 @@ func (nextjs) Generate(ctx context.Context, opts *Options) error {
 	}
 
 	packageParams := nodepkg.InitPackageParams{
-		Name: "express",
-		Main: "dist/index.js",
+		Name: "nextjs",
 		Scripts: map[string]string{
 			"lint-check": "next lint && prettier --check .",
 			"lint-fix":   "(next lint --fix || true) && prettier --write .",
 		}}
 
 	if err := nodepkg.InitPackage(frontendDir, packageParams); err != nil {
-		return fmt.Errorf("write src/index.ts: %w", err)
+		return fmt.Errorf("init nextjs package.json: %w", err)
 	}
 
 	return nil
@@ -108,8 +107,7 @@ func (nextjs) Post(ctx context.Context, opts *Options) error {
 	if err := fsutil.Fs.MkdirAll(dir, 0o755); err != nil {
 		return fmt.Errorf("mkdir %s: %w", dir, err)
 	}
-	content := `NEXT_PUBLIC_BACKEND_URL=http://localhost:4000
-        `
+	content := `NEXT_PUBLIC_BACKEND_URL=http://localhost:4000`
 	if err := afero.WriteFile(fsutil.Fs, envPath, []byte(content), 0o644); err != nil {
 		return fmt.Errorf("write %s: %w", envPath, err)
 	}
diff --git a/internal/stacks/templates/express/src/index.ts.tmpl b/internal/stacks/templates/express/src/index.ts.tmpl
index 7559191..dce0cc4 100644
--- a/internal/stacks/templates/express/src/index.ts.tmpl
+++ b/internal/stacks/templates/express/src/index.ts.tmpl
@@ -4,7 +4,7 @@ import cors from "cors"; // connects to frontend
 // [DATABASE IMPORT]
 
 const app = express();
-const PORT = process.env.PORT || 3000;
+const PORT = process.env.PORT || 4000;
 
 app.use(express.json());