---
title: "New free tool: AI Dockerfile Generator from any public repo"
description: Paste a public repo URL and get a production-ready Dockerfile in seconds. Multi-stage builds, pinned versions, non-root user — all inferred from the actual source code. Works on 250+ languages and frameworks.
date: 2026-05-04
author: Alex Sofroniev
tags: [docker, devops, developer tools, ai, containerization]
image: /OG.png
---

Every time a team says "we'll Dockerize it later," that later never comes. The blocker is rarely Docker itself — it's deciding on the right base image, build steps, exposed port, and runtime command for a codebase you don't fully remember. Today we're shipping a tool that removes that blocker entirely.

**ShipDocs' AI Dockerfile Generator** reads any public GitHub, GitLab, or Bitbucket repo and writes a production-ready Dockerfile from the actual source. It detects the language from `package.json`, `go.mod`, `Cargo.toml`, `requirements.txt`, and 250+ other manifest files, then builds the right multi-stage image with pinned versions, proper layer caching, and a non-root user when possible. No more `FROM ubuntu` + `apt-get install` copy-pasta.

## What it does

Paste a repo URL at [shipdocs.sh/tools/dockerfile](https://shipdocs.sh/tools/dockerfile) and you get:

- **Detected runtime** — Node 20-alpine, Python 3.12-slim, Go 1.22, Rust 1.75, or whatever the manifest says.
- **Multi-stage build** — compile in one layer, ship only the binary in a second. No build tools in the final image.
- **Pinned base image versions** — `node:20-alpine`, not `node:alpine`. Reproducible builds, no surprise breakages.
- **Correct build commands** — `npm ci`, `go build`, `cargo build --release`, `pip install -r requirements.txt` — inferred from the actual manifest, not guessed.
- **Sensible `EXPOSE`** — detects the port from the entry point or a config file when possible.
- **Non-root `USER`** — runs as an unprivileged user in the final stage when the runtime supports it.
- **Comments** — every non-obvious choice is explained inline so you can tweak it.

## Try it on these repos

| Repo | Why it's interesting |
|------|---------------------|
| `github.com/vercel/next.js` | Complex monorepo with Turbopack, TypeScript, multiple build targets |
| `github.com/kubernetes/kubernetes` | Multi-language, custom build scripts, Go modules |
| `github.com/supabase/supabase` | Docker Compose already present — see how the tool handles existing infra |
| `github.com/t3-oss/create-t3-app` | Modern TypeScript stack with Prisma, tRPC, Next.js |

Just paste the URL and hit Generate. No signup, no API key, no credit card. The tool is rate-limited to 5 runs per IP per 10 minutes to keep costs sane.

## How it works under the hood

The Dockerfile Generator uses the same repo indexer that powers ShipDocs' documentation engine:

1. **Clone** the repo via `isomorphic-git` (public repos only for the free tool).
2. **Filter** to source + manifest files — code, configs, build scripts.
3. **Prioritize** the most informative files: the README, root manifest (`package.json`, `go.mod`, etc.), entry points (`main.go`, `app.py`, `index.ts`), and a sample of the actual source.
4. **Send to an LLM** with a system prompt that says "you are a senior DevOps engineer writing a Dockerfile. Ground every choice in the source shown to you."
5. **Return** the raw Dockerfile text with no markdown wrapper so you can copy-paste it directly.

The model is Llama 3.1 8B via OpenRouter on the free tier — fast, cheap, and good enough for Dockerfile inference on most stacks. Paid ShipDocs users get the same tool on Claude Sonnet for private repos.

## Private repos too

If you connect a private repo to ShipDocs (Starter plan and up), the Dockerfile Generator shows up as a button inside your project's docs page. It reads the already-indexed source files — no re-clone needed — and uses Claude Sonnet instead of Llama for higher-quality output on complex monorepos.

## Limitations

Dockerfile generation is not magic. The tool works best when:

- The repo has a recognizable manifest file (`package.json`, `go.mod`, `Cargo.toml`, `pyproject.toml`, `requirements.txt`, `pom.xml`, etc.)
- The entry point is in a standard location or named conventionally (`main.go`, `app.py`, `server.ts`, etc.)
- The build process is documented in the README or the manifest scripts

It will struggle with:

- Projects that require complex external build pipelines (Bazel monorepos with custom rules, for example)
- Projects with heavy native dependencies that need system libraries not available in Alpine
- Highly unusual directory layouts with no manifest at all

In those cases, the generated Dockerfile is still a useful starting point — but you'll need to hand-tune it.

## What's next

The Dockerfile Generator is the fourth free tool on ShipDocs, joining the README Generator, Complexity Score, and Explain-in-a-Tweet. The fifth — a Production Readiness Audit that scores any repo on docs, CI, tests, secrets hygiene, and dependency health — ships next week.

Try the Dockerfile Generator now:

→ [**shipdocs.sh/tools/dockerfile**](https://shipdocs.sh/tools/dockerfile)

No signup required. Paste a repo URL, get a Dockerfile.