Try it

Language / runtime

Base image version

Exposed port

Working directory

Install command (optional)

Build command (optional)

Start command (optional)

Multi-stage build

Run as a non-root user

File: Dockerfile
Stages: runtime
Content: # Generated in the browser — review this file and adapt it to your project before committing. FROM node:20-alpine WORKDIR /app COPY . . RUN npm ci RUN npm run build EXPOSE 3000 RUN addgroup -S app && adduser -S app -G app USER app CMD ["sh", "-c", "npm start"]

# Generated in the browser — review this file and adapt it to your project before committing.
FROM node:20-alpine
WORKDIR /app
COPY . .
RUN npm ci
RUN npm run build
EXPOSE 3000
RUN addgroup -S app && adduser -S app -G app
USER app
CMD ["sh", "-c", "npm start"]

Supported formats

Input: text
Output: text

Privacy

Runs entirely in your browser. Your input is never uploaded, stored, or sent to a third party.

Processing: In your browser
Privacy level: Browser only

Generated a 2-stage Dockerfile for go.

How it works

Selected the go:1.22 base image.
Emitted a builder stage and a smaller runtime stage that copies only the build output.
Exposed port 8080 and set the start command.

The Dockerfile is a starting point: review the base image, commands and user before building.
No secret or credential is written into the file; pass secrets at build or run time.

Methodology

Resolve the language and version to a builder/runtime base image.
Emit `FROM`, `WORKDIR`, `COPY`, install and build instructions in a valid order.
For a compiled target emit a second runtime stage and copy the build output with `COPY --from`; add `EXPOSE`, the optional non-root user and the start command.

Usage

Choose the language/runtime and base image version.
Set the port, workdir and the install/build/start commands.
Choose multi-stage and non-root, then copy or download the Dockerfile.

Examples

These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.

Multi-stage Go service

{
  "language": "go",
  "version": "1.22",
  "port": 8080,
  "workdir": "/app",
  "installCommand": "",
  "buildCommand": "",
  "startCommand": "",
  "multiStage": true,
  "nonRoot": false
}

Node service on port 3000

{
  "language": "node",
  "version": "20",
  "port": 3000,
  "workdir": "/app",
  "installCommand": "npm ci --omit=dev",
  "buildCommand": "",
  "startCommand": "npm start",
  "multiStage": false,
  "nonRoot": true
}

Limitations

What changes between a single-stage and a multi-stage build

A single-stage Dockerfile is shorter and easier to read, but it ships the build toolchain in the final image. A multi-stage Dockerfile builds in one image and copies only the artifact into a smaller runtime image.

The generator picks the pattern based on the language; you can override it and edit the result.

Frequently asked questions

Why a multi-stage build?: Compiled languages and static sites need their build toolchain only at build time. A second stage starts from a small runtime image and copies just the output, which keeps the final image smaller.
Are secrets written into the Dockerfile?: No. The tool never embeds a credential; pass secrets at build or run time instead.

Sources

Dockerfile reference — Docker
Docker build best practices — Docker

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