Getting started

Harmont runs CI against your local working tree with hm run, so you can put a change through CI before you commit it. This guide takes you from an empty repo to a passing build.

Install hm

curl -fsSL https://get.harmont.dev/install.sh | sh

The script downloads the static binary for your platform, verifies its SHA-256 against https://get.harmont.dev/sha256sums.txt, and installs to ~/.local/bin/hm. Confirm it works:

hm --version

You also need Docker running locally; hm run executes each step in a container.

Scaffold a pipeline with hm init

Run hm init in your project. It asks which kind of project you have and writes a ready-to-run starter pipeline to .hm/:

hm init

? Select a project template ›
  CMake
  Elixir
  Next.js
  JavaScript / TypeScript
❯ Rust
  Zig
  Python

Pick one (or skip the prompt with hm init --template rust) and hm init writes .hm/pipeline.py (or .hm/pipeline.ts for the Next.js, JavaScript/TypeScript, and Zig templates). For example, the Rust template:

import harmont as hm
from harmont._rust import RustToolchain


@hm.target()
def project() -> RustToolchain:
    return hm.rust.toolchain(path=".")


@hm.pipeline(
    "ci",
    env={"CI": "true"},
    default_image="ubuntu:24.04",
    triggers=[hm.push(branch="main")],
)
def ci(project: hm.Target[RustToolchain]) -> tuple[hm.Step, ...]:
    return (project.build(), project.test(), project.clippy(), project.fmt())

Run it

hm run ci

hm run packs your working tree, boots a local sandbox, and streams the build:

Packing working tree (6 files, 12 KB)... done.
Build #1 created. Streaming logs.

  rust-install   ✓  2.1s
  build          ✓  3.4s
  test           ✓  0.9s

Build passed in 6.4s.

Grow the pipeline

Two rules cover most pipelines:

• A step built off another runs after it and inherits its filesystem. That's a sequence.
• Steps returned together with no dependency between them run in parallel.

To go deeper, read the Pipeline SDK guide. For complete, runnable projects in other languages, see Examples.

Get help

Stuck on a step, or want to see how others structure their pipelines? Join the Harmont Discord — it's the fastest way to get an answer from the team and the community.