NixCI vs GitHub Actions

NixCI GitHub Actions
"Just" Works
Configuration is entirely optional
Automatic flake output discovery
No vendor lock-in
Locally reproducible
Repro commands provided per job
Every job reproducible locally
Multi-forge support
GitLab.com support
Self-hosted GitLab support
Codeberg.org support
Self-hosted Forgejo support
Multiple forges in one installation
GitHub.com support
Self-hosted GitHub support
Automatic binary caching
Automatic binary caching
Cachix support
Own cache support
Workers
Hosted worker vCPUs 16 vCPUs 4 vCPUs
Hosted worker RAM 64 GB 16 GB
Bring your own workers
Continuous deployment
Impure tests with secrets
Continuous deployment
Self-hostable
Self-hostable leader
Self-hostable worker
FlakeHub
FlakeHub support

If you spot an inaccuracy in this table, please let us know .

"Just" Works

Configuration is entirely optional

NixCI reads your flake.nix and automatically discovers what to build. All configuration is optional. If it builds with nix flake check locally, it builds on NixCI.

GitHub Actions requires YAML workflow files that specify each step: installing Nix, configuring caches, and listing what to build.

Automatic flake output discovery

NixCI automatically discovers all flake outputs and creates build jobs for them.

No vendor lock-in

NixCI uses standard Nix flakes. Your build definition is your flake.nix, which works everywhere Nix does.

GitHub Actions uses GitHub-specific YAML workflow files.

Locally reproducible

Repro commands provided per job

NixCI provides the exact command to reproduce each job locally, including for impure tests and deployments.

Every job reproducible locally

Every job on NixCI can be reproduced locally with a single command.  NixCI shows you the exact command for each job, so when CI fails, you can start fixing it immediately on your machine.

Via act  .

Multi-forge support

GitLab.com support

NixCI integrates with GitLab.com via webhooks and commit status updates.

Self-hosted GitLab support

NixCI supports self-hosted GitLab instances.

Codeberg.org support

NixCI integrates with Codeberg.org via webhooks and commit status updates.

Self-hosted Forgejo support

NixCI supports self-hosted Forgejo instances.

Multiple forges in one installation

A single NixCI installation can serve GitHub, GitLab, and Codeberg repositories simultaneously.

GitHub.com support

NixCI works with GitHub  , GitLab  , and Codeberg  . One CI system across all your forges.

Self-hosted GitHub support

NixCI supports self-hosted GitHub Enterprise instances.

Automatic binary caching

Automatic binary caching

NixCI caches automatically without any configuration. Every build result is cached and subsequent builds pull from the cache to skip work that's already been done.

Using a binary cache with GitHub Actions requires configuring a third-party action and managing cache credentials.

Cachix support

NixCI has built-in Cachix support. Just add your Cachix cache name to your configuration.

GitHub Actions supports Cachix via a third-party action, but it requires manual setup.

Own cache support

NixCI can push build results to your own binary cache via SSH.

GitHub Actions can push to your own binary cache, but it requires manual setup.

Hosted worker vCPUs

NixCI's hosted workers have 16 vCPUs and 64 GB of RAM, billed per second of actual build time. You can also bring your own workers with whatever hardware you choose.

GitHub Actions' standard runners have 4 vCPUs and 16 GB of RAM, billed per minute rounded up.

Continuous deployment

Impure tests with secrets

NixCI has built-in support for continuous deployment and impure tests with access to secrets and the network.

In GitHub Actions, all tests run with full network and secret access by default. There is no distinction between pure and impure tests.

Continuous deployment

NixCI automatically runs deployment after all builds and tests pass, with no manual dependency declaration needed.

GitHub Actions supports deployment, but you have to manually declare which jobs must pass before deployment runs.

Self-hostable leader

NixCI can be fully self-hosted on your own infrastructure, including the leader, workers, and cache. It also works with self-hosted forges like GitLab and Forgejo.

GitHub is self-hostable. You can run your own GitHub instance with runners.

FlakeHub support

NixCI does not have FlakeHub integration. FlakeHub only allows publishing from trusted platforms  .

GitHub Actions has official FlakeHub support for publishing and caching.

Set up NixCI for GitHub