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MicroShift 2.0

Lightweight single-node Kubernetes for edge, built on Fedora-packaged components.

What is this?

A from-scratch reimplementation of MicroShift. Instead of embedding K8s components as Go libraries in a monolithic binary, this project is a thin Go daemon that orchestrates separate systemd services using binaries from Fedora's kubernetes1.35 packages.

Architecture

MicroShift is a daemon (microshift.service) that:

  1. Generates TLS certificates and kubeconfig files
  2. Writes configuration for each K8s component
  3. Manages component lifecycle via systemd D-Bus
  4. Bootstraps the cluster (applies kindnet, CoreDNS manifests)
  5. Monitors health

Components run as separate systemd services:

  • microshift-etcd.service
  • microshift-apiserver.service
  • microshift-controller-manager.service
  • microshift-scheduler.service
  • microshift-kubelet.service
  • microshift-kube-proxy.service

All have PartOf=microshift.service — stopping MicroShift stops everything.

Build

make build    # builds bin/microshift
make test     # runs unit tests
make lint     # runs golangci-lint
make install  # installs binary, systemd units, assets

Project layout

  • cmd/microshift/ — CLI entry point
  • pkg/config/ — configuration loading and defaults
  • pkg/certs/ — TLS certificate generation
  • pkg/kubeconfig/ — kubeconfig file generation
  • pkg/services/ — systemd service management and component config generation
  • pkg/bootstrap/ — cluster bootstrap (manifest application)
  • pkg/healthcheck/ — component health monitoring
  • pkg/daemon/ — main daemon orchestration loop
  • assets/ — embedded K8s manifests (kindnet, coredns, kubeproxy, rbac, storage)
  • packaging/ — RPM spec, systemd units, default config
  • images/ — bootc Containerfile, Fedora spin kickstart

Key conventions

  • Go module: github.com/ausil/microshift-2.0
  • Config file: /etc/microshift/config.yaml
  • Data directory: /var/lib/microshift/ (certs, kubeconfigs, component configs, etcd data)
  • Targets Fedora IoT with kubernetes1.35, etcd, cri-o1.35, containernetworking-plugins
  • Kindnet and CoreDNS run as pods (not host packages)
  • Apache-2.0 license

Dependencies

Host packages (from Fedora repos):

  • kubernetes1.35 — kube-apiserver, kube-controller-manager, kube-scheduler, kubelet
  • etcd — cluster state store
  • cri-o1.35 — container runtime
  • containernetworking-plugins — CNI plugins (bridge, host-local)

Go dependencies:

  • github.com/coreos/go-systemd/v22 — systemd D-Bus integration
  • gopkg.in/yaml.v3 — config file parsing