Core Concepts of Flux.
Flux is a tool for keeping Kubernetes clusters in sync with sources of configuration (like Git repositories), and automating updates to configuration when there is new code to deploy.
Flux is built from the ground up to use Kubernetes' API extension system, and to integrate with Prometheus and other core components of the Kubernetes ecosystem. Flux supports multi-tenancy and support for syncing an arbitrary number of Git repositories.
Flux Works Well With
Flux very naturally integrates with these pieces* of best-practice Open Source software (from the CNCF Landscape and elsewhere). Click on the logo to see how to set it up with Flux.
* This list is of course only a small selection of tools we integrate with. If you want to add more, please send a PR with the link to docs which explain how to set things up.
Flux in Short
|🤝 Flux provides GitOps for both apps and infrastructure||Flux and Flagger deploy apps with canaries, feature flags, and A/B rollouts. Flux can also manage any Kubernetes resource. Infrastructure and workload dependency management is built in.|
|🤖 Just push to Git and Flux does the rest||Flux enables application deployment (CD) and (with the help of Flagger) progressive delivery (PD) through automatic reconciliation. Flux can even push back to Git for you with automated container image updates to Git (image scanning and patching).|
|🔩 Flux works with your existing tools||Flux works with your Git providers (GitHub, GitLab, Bitbucket, can even use s3-compatible buckets as a source), all major container registries, and all CI workflow providers.|
|🔒 Flux is designed with security in mind||Pull vs. Push, least amount of privileges, adherence to Kubernetes security policies and tight integration with security tools and best-practices. Read more about our security considerations.|
|☸️ Flux works with any Kubernetes and all common Kubernetes tooling||Kustomize, Helm, RBAC, and policy-driven validation (OPA, Kyverno, admission controllers) so it simply falls into place.|
|🤹 Flux does Multi-Tenancy (and “Multi-everything”)||Flux uses true Kubernetes RBAC via impersonation and supports multiple Git repositories. Multi-cluster infrastructure and apps work out of the box with Cluster API: Flux can use one Kubernetes cluster to manage apps in either the same or other clusters, spin up additional clusters themselves, and manage clusters including lifecycle and fleets.|
|📞 Flux alerts and notifies||Flux provides health assessments, alerting to external systems, and external events handling. Just “git push”, and get notified on Slack and other chat systems.|
|👍 Users trust Flux||Flux is a CNCF Incubating project and was categorised as “Adopt” on the CNCF CI/CD Tech Radar (alongside Helm).|
|💖 Flux has a lovely community that is very easy to work with!||We welcome contributors of any kind. The components of Flux are on Kubernetes core |
Who is Flux for?
- cluster operators who automate provision and configuration of clusters;
- platform engineers who build continuous delivery for developer teams;
- app developers who rely on continuous delivery to get their code live.
What can I do with Flux?
Flux is based on a set of Kubernetes API extensions (“custom
resources”), which control how git repositories and other sources of
configuration are applied into the cluster (“synced”).
For example, you create a
GitRepository object to mirror
configuration from a Git repository, then a
Kustomization object to
sync that configuration.
Flux works with Kubernetes’ role-based access control (RBAC), so you can lock down what any particular sync can change. It can send notifications to Slack and other like systems when configuration is synced and ready, and receive webhooks to tell it when to sync.
flux command-line tool is a convenient way to bootstrap the
system in a cluster, and to access the custom resources that make up
Where do I start?
Get started with Flux!Following this guide will just take a couple of minutes to complete: After installing the
fluxCLI and running a couple of very simple commands, you will have a GitOps workflow setup which involves a staging and a production cluster.
If you should need help, please refer to our Support page.
More detail on what’s in Flux
- Source configuration from Git and Helm repositories, and S3-compatible buckets (e.g., Minio)
- Kustomize and Helm support
- Event-triggered and periodic reconciliation
- Integration with Kubernetes RBAC
- Health assessment (clusters and workloads)
- Dependency management (infrastructure and workloads)
- Alerting to external systems (webhook senders)
- External events handling (webhook receivers)
- Automated container image updates to Git (image scanning and patching)
- Policy-driven validation (OPA, Kyverno, admission controllers)
- Seamless integration with Git providers (GitHub, GitLab, Bitbucket)
- Interoperability with workflow providers (GitHub Actions, Tekton, Argo)
- Interoperability with Cluster API (CAPI) providers
What is the GitOps Toolkit?
Flux is constructed with the GitOps Toolkit components, which is a set of
- specialized tools and Flux Controllers
- composable APIs
- reusable Go packages for GitOps under the fluxcd GitHub organisation
for building Continuous Delivery on top of Kubernetes.
The GitOps Toolkit can be used individually by platform engineers who want to make their own continuous delivery system, and have requirements not covered by Flux.
Need help or want to contribute? Please see the links below. The Flux project is always looking for new contributors and there are a multitude of ways to get involved.
- Getting Started?
- Look at our Get Started guide and give us feedback
- Need help?
- First: Ask questions on our GH Discussions page
- Second: Talk to us in the #flux channel on CNCF Slack
- Please follow our Support Guidelines (in short: be nice, be respectful of volunteers’ time, understand that maintainers and contributors cannot respond to all DMs, and keep discussions in the public #flux channel as much as possible).
- Have feature proposals or want to contribute?
Check out our events calendar, both with upcoming talks you can attend or past events videos you can watch.
We look forward to seeing you with us!
Get Started with Flux.
Flux install, bootstrap, upgrade and uninstall documentation.
Flux user guides.
Flux use cases.
Migration guides for Flux v1 and Helm Operator users.
Documentation of the individual GitOps Toolkit components and their APIs.
The GitOps Toolkit development documentation.
A narrative of the life of a commit as it relates to Flux components.
The Flux Command-Line Interface documentation.
Flux and the GitOps Toolkit frequently asked questions.
Flux Security documentation.