Flynn

Flynn is an open source Platform as a Service (PaaS). It is designed to run anything that can run on Linux, not just stateless web apps. Flynn comes with highly available database appliances, including PostgreSQL, MySQL, and MongoDB.

Flynn was originally created by Jeff Lindsay, Jonathan Rudenberg, and the team at Prime Directive, Inc., along with a vibrant open source community. This repository is a continuation of that work, focused on rebuilding Flynn from its unmaintained state with modernized infrastructure.

Status

Flynn is under active reconstruction. The original release infrastructure (dl.flynn.io, releases.flynn.io) went offline, and the project's self-hosting build system depended on it. This fork restores Flynn to a buildable, testable, and deployable state.

What has been completed:

• New TUF (The Update Framework) repository for secure component distribution
• Containerized development environment (no running cluster required to build)
• All 34 component binaries compile from source
• Go version upgraded from 1.13 to 1.22
• CI pipeline via GitHub Actions (build + unit tests)
• End-to-end verified: flynn-host download pulls images from the new TUF repo

What is in progress:

• Integration testing and cluster bootstrap (discoverd, flannel, controller)
• runc fork modernization (security patches, cgroups v2)

Repository Layout

This repository (flynn/) is a Go monorepo (module github.com/flynn/flynn).

Directory	Description
host/	flynn-host daemon — container management via libcontainer
controller/	API server, scheduler, worker
cli/	flynn CLI tool
bootstrap/	Cluster bootstrap actions and manifest
builder/	Build system, component image definitions
discoverd/	Service discovery
flannel/	Container networking (overlay network)
router/	HTTP/TCP router (L7/L4 load balancer)
appliance/	Database appliances (PostgreSQL, MariaDB, MongoDB, Redis)
logaggregator/	Log collection and streaming
blobstore/	Binary large object storage
pkg/	Shared Go packages
schema/	JSON schemas for controller and router APIs
script/	Build, release, and test orchestration scripts
vendor/	Vendored Go dependencies
test/	Integration test runner and test applications

Getting Started

Building from source

Flynn requires a Linux environment with CGO support. The recommended approach is to use the containerized dev environment:

# Build core components manually
go build ./host       # flynn-host (requires CGO, Linux)
go build ./cli        # flynn CLI
go build ./controller # flynn-controller

# Build all 34 components at once
make bootstrap-build

Running unit tests

# Run standalone unit tests (no cluster required)
make test-unit-standalone

# Run specific package tests
go test ./pkg/cors/...
go test ./discoverd/health/...

Contributing

We welcome and encourage community contributions to Flynn.

There are many ways to help:

• Find bugs and file issues
• Improve documentation
• Submit pull requests

Please report issues on this repository after searching to see if anyone has already reported the issue.

Licensing

Flynn is licensed under the BSD 3-Clause license. The original copyright is held by Prime Directive, Inc. See LICENSE for details.