liminfoDockerfile Generator
Free web tool: Dockerfile Generator
Generated Dockerfile
# Build stage
FROM node:22-slim AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci
COPY . .
RUN npm ci && npm run build
# Production stage
FROM node:22-slim
WORKDIR /app
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/package*.json ./
EXPOSE 3000
CMD ["node", "dist/index.js"]About Dockerfile Generator
The Dockerfile Generator creates production-ready Dockerfiles for five major runtimes — Node.js, Python, Go, Rust, and Java — with configurable version, port, and multi-stage build options. Select your language and version from the dropdowns, enter the container port, and toggle multi-stage builds on or off. The Dockerfile is generated instantly in the browser and can be copied to your clipboard with one click.
Multi-stage builds are enabled by default. For Node.js, the build stage installs dependencies with npm ci and compiles to the dist directory, then the production stage copies only the built artifacts and node_modules — keeping the final image small. Go and Rust use distroless or minimal base images in the production stage to produce lean, secure container images. Java uses a JDK image for building and a JRE image for running. Python copies site-packages from the build stage.
This generator is designed for backend engineers, DevOps practitioners, and developers learning containerization. All generation logic runs entirely in the browser using React's useMemo hook — no server call is made, and nothing is stored. The output follows Dockerfile best practices including WORKDIR, COPY with dependency files first (for layer caching), and proper CMD array syntax.
Key Features
- Supports Node.js (22/20/18/16), Python (3.13–3.10), Go (1.23–1.21), Rust (1.80–1.78), Java (21/17/11)
- Multi-stage build option for smaller, more secure production images
- Go production stage uses gcr.io/distroless/static-debian12 for minimal attack surface
- Rust production stage uses debian:bookworm-slim with only ca-certificates
- Java uses eclipse-temurin JDK for build and JRE for the production stage
- Configurable EXPOSE port with automatic CMD array formatting
- One-click copy of the generated Dockerfile to clipboard
- Real-time generation — output updates instantly as you change any option
Frequently Asked Questions
What languages does this Dockerfile generator support?
The generator supports five languages: Node.js (versions 22, 20, 18, 16), Python (3.13, 3.12, 3.11, 3.10), Go (1.23, 1.22, 1.21), Rust (1.80, 1.79, 1.78), and Java (21, 17, 11 using Eclipse Temurin). Each language uses its official Docker Hub base image with a slim or minimal variant.
What is a multi-stage build and why should I use it?
A multi-stage build uses multiple FROM instructions in a single Dockerfile. The first stage (builder) compiles the application, and the second stage copies only the necessary runtime artifacts. This results in a much smaller final image because build tools, source code, and intermediate files are not included. For production deployments, multi-stage builds are strongly recommended.
Why does the Go Dockerfile use a distroless base image?
Go compiles to a statically linked binary that does not depend on dynamic libraries. The gcr.io/distroless/static-debian12 image contains only the bare minimum needed to run such binaries — no shell, no package manager, and no unnecessary OS utilities. This dramatically reduces the attack surface and image size.
How do I customize the generated Dockerfile further?
Copy the generated Dockerfile to your editor and add your customizations: environment variables with ENV, build arguments with ARG, health checks with HEALTHCHECK, non-root user setup with USER, or additional RUN commands for system dependencies. The generator creates a solid starting point that you can adapt to your project's specific needs.
What build command does the Node.js Dockerfile use?
For single-stage builds, the Node.js Dockerfile runs "npm ci && npm run build". For multi-stage builds, the builder stage runs "npm ci" to install dependencies, then "npm ci && npm run build" to compile. The production stage copies the dist directory, node_modules, and package*.json files from the builder stage.
Can I use this for TypeScript projects?
Yes. The Node.js Dockerfile assumes a build step that compiles TypeScript to the dist directory using "npm run build". Make sure your package.json has a build script (e.g., "tsc") and that your tsconfig.json outputs to the dist directory. The generated CMD runs "node dist/index.js".
What port does the generator use by default?
The default port is 3000, which is common for Node.js applications. You can change it to any valid port number — 8000 for Python/Django, 8080 for Go/Java, 3001 for alternative Node.js ports, and so on. The EXPOSE instruction in Docker is documentation only; you still need to publish the port with -p when running the container.
Is the generated Dockerfile safe for production use?
The generated Dockerfile follows common best practices (slim base images, dependency layer caching, multi-stage builds, proper CMD syntax). However, you should review and adapt it for your specific security requirements — adding a non-root USER, setting resource limits, pinning exact image digests, and adding health checks before deploying to production.