ZeroServer.tools

Dockerfile Generator

Build a Dockerfile from a form. Choose base image, working directory, ports, commands, and environment variables.

Presets

Base

FROM (base image)

WORKDIR

EXPOSE port

USER

Steps

COPY (deps first)

RUN

COPY (app)

CMD (start command)

Optional

ENV vars (one per line)

LABEL (one per line)

HEALTHCHECK

Dockerfile

FROM node:18-alpine

WORKDIR /app

ENV NODE_ENV=production

COPY package*.json ./
RUN npm ci --only=production

COPY . .

USER node
EXPOSE 3000

CMD ["node", "index.js"]

Dockerfile best practices

A Dockerfile is a script that defines how to build a Docker container image. Key best practices: use minimal base images (alpine variants), copy package files before source code to leverage layer caching, install only production dependencies, run as a non-root user, and use EXPOSE to document which ports the container listens on. Multi-stage builds (FROM ... AS builder) reduce final image size by separating build and runtime layers.

Private & free — this tool runs entirely in your browser.