awesome-copilot/skills/acquire-codebase-knowledge/references/stack-detection.md

Stack Detection Reference

Load this file when the tech stack is ambiguous — e.g., multiple manifest files present, unfamiliar file extensions, or no obvious package.json / go.mod.

---

Manifest File → Ecosystem

File	Ecosystem	Key fields to read
package.json	Node.js / JavaScript / TypeScript	dependencies, devDependencies, scripts, main, type, engines
go.mod	Go	Module path, Go version, require block
requirements.txt	Python (pip)	Package list with pinned versions
Pipfile	Python (pipenv)	[packages], [dev-packages], [requires] python version
pyproject.toml	Python (poetry / uv / hatch)	[tool.poetry.dependencies], [project], [build-system]
setup.py / setup.cfg	Python (setuptools, legacy)	install_requires, python_requires
Cargo.toml	Rust	[dependencies], [[bin]], [lib]
pom.xml	Java / Kotlin (Maven)	<dependencies>, <artifactId>, <groupId>, <java.version>
build.gradle / build.gradle.kts	Java / Kotlin (Gradle)	dependencies {}, sourceCompatibility
composer.json	PHP	require, require-dev
Gemfile	Ruby	gem declarations, ruby version constraint
mix.exs	Elixir	deps/0, elixir: "~> X.Y"
pubspec.yaml	Dart / Flutter	dependencies, dev_dependencies, environment.sdk
*.csproj	.NET / C#	<PackageReference>, <TargetFramework>
*.sln	.NET solution	References multiple .csproj projects
deno.json / deno.jsonc	Deno (TypeScript runtime)	imports, tasks
bun.lockb	Bun (JavaScript runtime)	Binary lockfile — check package.json for deps

---

Language Runtime Version Detection

Language	Where to find the version
Node.js	.nvmrc, .node-version, engines.node in package.json, Docker FROM node:X
Python	.python-version, pyproject.toml [requires-python], Docker FROM python:X
Go	First line of go.mod (go 1.21)
Java	<java.version> in pom.xml, sourceCompatibility in build.gradle, Docker FROM eclipse-temurin:X
Ruby	.ruby-version, Gemfile ruby 'X.Y.Z'
Rust	rust-toolchain.toml, rust-toolchain file
.NET	<TargetFramework> in .csproj (e.g., net8.0)

---

Framework Detection (Node.js / TypeScript)

Dependency in package.json	Framework
express	Express.js (minimal HTTP server)
fastify	Fastify (high-performance HTTP server)
next	Next.js (SSR/SSG React — check for pages/ or app/ directory)
nuxt	Nuxt.js (SSR/SSG Vue)
@nestjs/core	NestJS (opinionated Node.js framework with DI)
koa	Koa (middleware-focused, no built-in router)
@hapi/hapi	Hapi
@trpc/server	tRPC (type-safe API without REST/GraphQL schemas)
routing-controllers	routing-controllers (decorator-based Express wrapper)
typeorm	TypeORM (SQL ORM with decorators)
prisma	Prisma (type-safe ORM, check prisma/schema.prisma)
mongoose	Mongoose (MongoDB ODM)
sequelize	Sequelize (SQL ORM)
drizzle-orm	Drizzle (lightweight SQL ORM)
react without next	Vanilla React SPA (check for react-router-dom)
vue without nuxt	Vanilla Vue SPA

---

Framework Detection (Python)

Package	Framework
fastapi	FastAPI (async REST, auto OpenAPI docs)
flask	Flask (minimal WSGI web framework)
django	Django (batteries-included, check settings.py)
starlette	Starlette (ASGI, often used as FastAPI base)
aiohttp	aiohttp (async HTTP client and server)
sqlalchemy	SQLAlchemy (SQL ORM; check for alembic migrations)
alembic	Alembic (SQLAlchemy migration tool)
pydantic	Pydantic (data validation; core to FastAPI)
celery	Celery (distributed task queue)

---

Monorepo Detection

Check these signals in order:

1. pnpm-workspace.yaml — pnpm workspaces
2. lerna.json — Lerna monorepo
3. nx.json — Nx monorepo (also check workspace.json)
4. turbo.json — Turborepo
5. rush.json — Rush (Microsoft monorepo manager)
6. moon.yml — Moon
7. package.json with "workspaces": [...] — npm/yarn workspaces
8. Presence of packages/, apps/, libs/, or services/ directories with their own package.json

If monorepo is detected: each workspace may have independent dependencies and conventions. Map each sub-package separately in STACK.md and note the monorepo structure in STRUCTURE.md.

---

TypeScript Path Alias Detection

If tsconfig.json has a paths key, imports with non-relative prefixes are aliases. Map them before documenting structure.

// tsconfig.json example
"paths": {
  "@/*": ["./src/*"],
  "@components/*": ["./src/components/*"],
  "@utils/*": ["./src/utils/*"]
}

Imports like import { foo } from '@/utils/bar' resolve to src/utils/bar. Document as src/utils/bar, not @/utils/bar.

---

Docker Base Image → Runtime

If no manifest file is present but a Dockerfile exists, the FROM line reveals the runtime:

FROM line pattern	Runtime
FROM node:X	Node.js X
FROM python:X	Python X
FROM golang:X	Go X
FROM eclipse-temurin:X	Java X (Eclipse Temurin JDK)
FROM mcr.microsoft.com/dotnet/aspnet:X	.NET X
FROM ruby:X	Ruby X
FROM rust:X	Rust X
FROM alpine (alone)	Check what's installed via RUN apk add