Earthly Has a Free API: Reproducible Builds That Work the Same Everywhere

Earthly is a build tool that combines the best of Dockerfiles and Makefiles. Every build runs in containers, so it works identically on your laptop and in CI. It's free, open source, and has a cloud service for caching and satellites.

Why Earthly?

• Reproducible — containerized builds, same result everywhere
• Familiar syntax — if you know Dockerfile + Makefile, you know Earthly
• Caching — automatic layer caching, shared across team via Earthly Cloud
• Multi-language — Go, Python, JS, Rust, Java — all in one Earthfile
• Parallelism — automatic parallel execution of independent targets

Install

# Linux/Mac
curl -sSfL https://github.com/earthly/earthly/releases/latest/download/earthly-$(uname -s)-$(uname -m) -o /usr/local/bin/earthly && chmod +x /usr/local/bin/earthly

# Or via brew
brew install earthly

# Bootstrap (sets up BuildKit)
earthly bootstrap

Earthfile (Like Dockerfile + Makefile)

# Earthfile
VERSION 0.8

# Base image with dependencies
deps:
    FROM node:20-alpine
    WORKDIR /app
    COPY package.json package-lock.json .
    RUN npm ci
    SAVE IMAGE --cache-hint

# Run tests
test:
    FROM +deps
    COPY src/ src/
    COPY tests/ tests/
    RUN npm test

# Build the app
build:
    FROM +deps
    COPY src/ src/
    RUN npm run build
    SAVE ARTIFACT dist/ /dist AS LOCAL ./dist

# Docker image
docker:
    FROM +build
    EXPOSE 3000
    CMD ["node", "dist/index.js"]
    SAVE IMAGE myapp:latest

# Run everything
all:
    BUILD +test
    BUILD +docker

# Run specific target
earthly +test

# Run all targets
earthly +all

# Build and push Docker image
earthly --push +docker

Multi-Language Monorepo

# Earthfile for monorepo
VERSION 0.8

# Go backend
backend-test:
    FROM golang:1.22-alpine
    WORKDIR /app
    COPY backend/go.mod backend/go.sum .
    RUN go mod download
    COPY backend/ .
    RUN go test ./...

backend-build:
    FROM +backend-test
    RUN go build -o server ./cmd/server
    SAVE ARTIFACT server /server

# Python ML service
ml-test:
    FROM python:3.12-slim
    WORKDIR /app
    COPY ml/requirements.txt .
    RUN pip install -r requirements.txt
    COPY ml/ .
    RUN pytest

# Frontend
frontend-build:
    FROM node:20-alpine
    WORKDIR /app
    COPY frontend/package*.json .
    RUN npm ci
    COPY frontend/ .
    RUN npm run build
    SAVE ARTIFACT build/ /build

# All tests in parallel (automatic!)
test-all:
    BUILD +backend-test
    BUILD +ml-test
    BUILD +frontend-build

CI Integration

# .github/workflows/ci.yml
name: CI
on: [push]
jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: earthly/actions-setup@v1
      - run: earthly +test-all

Earthly Cloud (Free Tier)

# Login to Earthly Cloud
earthly account login

# Use remote cache (team shares cache)
earthly --ci --remote-cache=myorg/myrepo +all

# Earthly Satellites (remote BuildKit)
earthly sat launch my-satellite
earthly --sat my-satellite +all

Key Features

Feature	Details
Syntax	Dockerfile + Makefile hybrid
Execution	Containerized (BuildKit)
Caching	Layer cache, remote cache
Parallelism	Automatic for independent targets
Artifacts	Export files or Docker images
CI	GitHub Actions, GitLab, Jenkins, etc.
Cloud	Free tier with remote caching

Resources

• Earthly Docs
• Earthfile Reference
• GitHub

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Need CI/CD optimization or custom build tools? Check my automation tools on Apify or email [e-mail].