uncloud/HACKING.md

Developing Uncloud

A short guide on setting up your local development environment.

Prerequisites

• mise (development environment setup tool)
• Docker with BuildKit (for running end-to-end tests). Make sure the docker buildx plugin is installed.

Setup

Uncloud uses mise to install and manage development tools and dependencies. It makes it easy to create reproducible development environments on developer machines and CI.

Follow the Installing Mise guide to get it set up on your machine.

Mark the project as trusted and install all required tools (Go, protoc, golangci-lint, etc.) by running from the project root:

mise trust
mise install

This reads mise.toml and installs the exact versions of tools specified there. They will be available in your PATH when you are in the project directory, so you can run go or golangci-lint directly. The tools won't be available outside the project, so they don't interfere with system packages.

Building

Build the CLI:

go build -o uc ./cmd/uc

Or build and run the CLI with a single command:

go run ./cmd/uc --help

The Uncloud daemon (uncloudd) only supports Linux, so you need to cross-compile it if you're developing on macOS or Windows:

GOOS=linux GOARCH=amd64 go build -o uncloudd ./cmd/uncloudd

Testing

Run all tests (unit and e2e):

make test

End-to-end tests

E2e tests run inside Docker using the Uncloud-in-Docker image. Build it first:

mise ucind:image

⚠️ NOTE: You need to rebuild the ucind image every time you make changes to the daemon code if you want to test them in e2e tests.

Then run the tests:

make test-e2e

If tests leave leftover containers, clean them up with:

make test-clean

Manual testing on dev machines

After making changes to the daemon code, you may want to test them in your dev cluster. Build and install uncloudd on one or multiple dev machines over SSH with:

mise run dev:install user@host1 user@host2/arm64

It will also restart the uncloud.service daemon on those machines to pick up the new version. The host format is [user@]host[/arch]. The architecture of a machine defaults to amd64 if not specified.

To stop the daemon and wipe all Uncloud data on the dev machines, run:

mise run dev:reset user@host1 user@host2

Linting and formatting

Lint and format the code:

make lint-and-fix

Code generation

Update the generated Go code for the machine gRPC API after modifying .proto files:

mise run proto

Regenerate mocks:

make mocks

Uncloud in Docker (UCinD)

The ucind CLI lets you run Uncloud clusters locally using Docker containers instead of real machines. Each cluster machine runs as a Docker container connected to a shared Docker network.

Cluster machines use the ghcr.io/psviderski/ucind:latest Docker image by default. It may not always have the latest changes to the uncloudd daemon code as it's not automatically rebuilt on CI yet.

You can rebuild it locally to pick up the latest changes, including your work in progress, and test them in a UCinD cluster:

mise ucind:image

Create a cluster with 3 machines:

mise ucind cluster create -m 3

This also sets the new cluster as the active context, so you can interact with it using the uc CLI right away.

Remove the cluster when you're done:

mise ucind cluster rm

Sometimes crashed tests or interrupted runs can leave orphaned containers and networks behind. Clean them all up with:

mise ucind:cleanup