btst init: @btst/codegen CLI tool

[olliethedev]

Overview

Add a btst init command to the @btst/codegen package that automatically scaffolds all the boilerplate required to integrate BTST into an existing Next.js (App Router), React Router v7, or TanStack Start project.

The install docs currently require ~8 steps of manual file creation and surgical edits to existing files. This command automates the entire flow end-to-end — detecting the framework, picking the right adapter, installing dependencies, generating files, and patching the root layout and CSS.

Think shadcn/ui's npx shadcn init — a single command that gets a project from zero to working without consulting documentation.

npx @btst/codegen init
# or if @btst/codegen is already installed:
codegen init

---

Core Features

Framework Detection & Selection

• Auto-detect framework from package.json deps (next, react-router, @tanstack/react-router)
• Prompt to confirm or override when multiple frameworks are found
• Detect path alias convention from tsconfig.json paths (@/, ~/, etc.)
• Detect package manager from lockfile (pnpm-lock.yaml, yarn.lock, package-lock.json)

Adapter Selection

• Interactive prompt to choose adapter: memory, prisma, drizzle, kysely, mongodb
• Install the corresponding @btst/adapter-* package automatically

Dependency Installation

• Install @btst/stack and @tanstack/react-query via detected package manager
• Install selected @btst/adapter-* package

Plugin Selection & Basic Config

• Prompt users to select one or more plugins to install during init (e.g. blog, comments, etc.)
• Install selected plugin package(s) automatically
• Scaffold basic backend + client plugin registration in lib/stack.ts and lib/stack-client.tsx
• Add required plugin CSS imports to global stylesheet
• Generate minimal override/config stubs in the framework layout for each selected plugin

File Generation

• lib/query-client.ts — shared QueryClient utility (identical across frameworks)
• lib/stack.ts — backend instance with selected adapter boilerplate
• lib/stack-client.tsx — client instance stub (createStackClient)
• Framework-specific API route handler:
  • Next.js: app/api/data/[[...all]]/route.ts
  • React Router: app/routes/api/data/route.ts
  • TanStack: src/routes/api/data/$.ts
• Framework-specific page handler (catch-all):
  • Next.js: app/pages/[[...all]]/page.tsx
  • React Router: app/routes/pages/index.tsx
  • TanStack: src/routes/pages/$.tsx
• Framework-specific StackProvider layout:
  • Next.js: app/pages/[[...all]]/layout.tsx
  • React Router: app/routes/pages/_layout.tsx
  • TanStack: src/routes/pages/route.tsx

Surgical File Patching

• Inject @import \"@btst/stack/...\" into the project's global CSS file (auto-detected or prompted)
• Wrap root layout / app entry with <QueryClientProvider> — attempted via AST transform (ts-morph), with printed fallback instructions if the file is non-standard
• Conflict handling for every generated file: skip / overwrite / show diff

Prerequisite Validation

• Warn (non-blocking) if components.json (shadcn) is absent
• Warn if Tailwind v4 is not detected in dependencies
• Warn if <Toaster /> (Sonner) is not present

---

Package Structure

packages/cli/
├── src/
│   ├── index.ts                      # commander entry — registers init + generate commands
│   ├── commands/
│   │   ├── init.ts                   # btst init — full project bootstrapping
│   │   └── generate.ts               # btst generate — existing DB schema codegen
│   ├── templates/
│   │   ├── shared/
│   │   │   └── lib/query-client.ts   # no templating needed; identical across frameworks
│   │   ├── nextjs/
│   │   │   ├── lib/stack.ts.hbs      # Handlebars template, one variant per adapter
│   │   │   ├── lib/stack-client.tsx.hbs
│   │   │   ├── app/api/data/[[...all]]/route.ts.hbs
│   │   │   ├── app/pages/[[...all]]/page.tsx.hbs
│   │   │   └── app/pages/[[...all]]/layout.tsx.hbs
│   │   ├── react-router/
│   │   │   ├── lib/stack.ts.hbs
│   │   │   ├── lib/stack-client.tsx.hbs
│   │   │   ├── app/routes/api/data/route.ts.hbs
│   │   │   ├── app/routes/pages/index.tsx.hbs
│   │   │   └── app/routes/pages/_layout.tsx.hbs
│   │   └── tanstack/
│   │       ├── lib/stack.ts.hbs
│   │       ├── lib/stack-client.tsx.hbs
│   │       ├── src/routes/api/data/$.ts.hbs
│   │       ├── src/routes/pages/$.tsx.hbs
│   │       └── src/routes/pages/route.tsx.hbs
│   └── utils/
│       ├── detect-framework.ts        # sniff package.json + folder layout
│       ├── detect-package-manager.ts  # lockfile detection
│       ├── detect-alias.ts            # read tsconfig.json paths
│       ├── detect-css-file.ts         # find globals.css / app.css
│       ├── file-writer.ts             # write + skip/overwrite/diff conflict UX
│       ├── package-installer.ts       # run pnpm/npm/yarn add
│       ├── css-patcher.ts             # inject @import line safely
│       └── layout-patcher.ts          # ts-morph AST wrap for QueryClientProvider
├── package.json
├── tsconfig.json
└── build.config.ts

---

Command Interface

btst init [options]

Options:
  --framework <name>    Skip detection prompt (nextjs | react-router | tanstack)
  --adapter <name>      Skip adapter prompt (memory | prisma | drizzle | kysely | mongodb)
  --skip-install        Skip dependency installation
  --cwd <path>          Run in a different directory (default: process.cwd())
  --yes                 Accept all defaults / overwrite all conflicts without prompting
  -h, --help            Show help

---

Interactive Prompt Flow

◆ Which framework are you using?
  ● Next.js (App Router)
  ○ React Router v7
  ○ TanStack Start

◆ Which database adapter?
  ● Memory (development / testing)
  ○ Prisma
  ○ Drizzle
  ○ Kysely
  ○ MongoDB

◆ Where is your global CSS file?
  app/globals.css

Installing dependencies with pnpm...
  + @btst/stack
  + @tanstack/react-query
  + @btst/adapter-memory

Writing files...
  ✔ lib/query-client.ts
  ✔ lib/stack.ts
  ✔ lib/stack-client.tsx
  ✔ app/api/data/[[...all]]/route.ts
  ✔ app/pages/[[...all]]/page.tsx
  ✔ app/pages/[[...all]]/layout.tsx

Patching files...
  ✔ app/globals.css       added @import \"@btst/stack/style.css\"
  ✔ app/layout.tsx        wrapped children with QueryClientProvider

◆ All done!

Next steps:
  → Add plugins to lib/stack.ts and lib/stack-client.tsx
  → Generate database schema: npx @btst/codegen generate --config=lib/stack.ts --orm=memory
  → Visit /pages to see plugin routes

---

Generated File Examples

lib/stack.ts (memory adapter, Next.js)

import { stack } from \"@btst/stack\"
import { createMemoryAdapter } from \"@btst/adapter-memory\"

let _stack: ReturnType<typeof stack> | undefined

function getStack() {
  if (!_stack) {
    _stack = stack({
      basePath: \"/api/data\",
      plugins: {
        // Add your backend plugins here
      },
      adapter: (db) => createMemoryAdapter(db)({}),
    })
  }
  return _stack
}

export const myStack = {
  get handler() { return getStack().handler },
  get api()     { return getStack().api },
  get adapter() { return getStack().adapter },
}

lib/stack-client.tsx

import { createStackClient } from \"@btst/stack/client\"
import type { QueryClient } from \"@tanstack/react-query\"

export const getStackClient = (queryClient: QueryClient) =>
  createStackClient({
    plugins: {
      // Add your client plugins here
    },
  })

---

Detection Heuristics

Signal	What it determines
package.json dep: next	Framework = Next.js
package.json dep: react-router	Framework = React Router
package.json dep: @tanstack/react-router	Framework = TanStack
pnpm-lock.yaml present	Package manager = pnpm
yarn.lock present	Package manager = yarn
tsconfig.json paths @/*	Alias = @/
tsconfig.json paths ~/*	Alias = ~/
components.json absent	Warn: shadcn not installed

---

Layout Patching Strategy

The root layout patch (QueryClientProvider wrap) uses ts-morph to parse the TSX AST and find the JSX return value. If patching succeeds silently, great. If the file is non-standard (class component, unusual structure), the patcher prints a clear diff block with manual instructions rather than failing:

⚠ Could not automatically patch app/layout.tsx.
  Add the following manually:

  import { QueryClientProvider } from \"@tanstack/react-query\"
  import { getOrCreateQueryClient } from \"@/lib/query-client\"

  // Wrap your root {children} with:
  <QueryClientProvider client={getOrCreateQueryClient()}>
    {children}
  </QueryClientProvider>

---

Non-Goals (v1)

• Scaffolding a brand-new framework project (wrapping create-next-app etc.) — init targets existing projects only
• Multi-monorepo-workspace awareness
• Adding plugins via btst init (that is a separate btst add command concern)
• Windows-specific path handling beyond basic normalisation
• Non-TypeScript projects

---

Implementation Notes

• Use @clack/prompts for the interactive prompt UX (same as shadcn CLI)
• Use commander for argument parsing
• Use ts-morph for AST-based layout patching
• Use handlebars for file templates (adapter × framework matrix)
• Use execa for running package manager commands
• Build with tsup or unbuild; ship as CJS + ESM with a bin entry

---

Package Configuration

{
  \"name\": \"@btst/codegen\",
  \"bin\": { \"btst\": \"./dist/index.cjs\" },
  \"scripts\": {
    \"build\": \"unbuild --clean\",
    \"dev\": \"tsx src/index.ts\"
  }
}

---

Documentation

Add docs/content/docs/cli.mdx (or extend the existing CLI page) covering:

• @btst/codegen init — full walkthrough
• Supported frameworks — Next.js, React Router, TanStack Start
• Supported adapters — all five, with links to adapter docs
• --yes flag — CI/CD usage
• Manual patching fallback — what to do when auto-patch fails