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flui.cloud

What Flui is

Flui is an open source platform for running applications. It sits on top of your cloud provider and gives you one way to operate every cloud it supports — the capabilities your provider doesn’t ship, and the freedom to grow without rewriting your platform.

The gap Flui exists to close

Where you run your software matters. Each kind of cloud gives you a very different experience.

Regional, sovereign and budget clouds — where Flui’s case is strongest

A large part of the cloud market is made of providers that sell you good machines at a good price and very little else: no managed Kubernetes, no integrated DNS with certificates, no identity provider, no observability, no ingress controller. You can build all of that yourself, but most teams don’t. The projects that try usually turn into unmaintainable side-projects.

This is where Flui’s case is strongest: bring a credential for one of these clouds and flui env create gives you the full stack — the same one a managed PaaS would.

Major hyperscalers

On the major clouds the building blocks already exist — managed Kubernetes, managed DNS, identity, observability. They work well, but they come with their own cost: vendor pricing, deep coupling to the provider’s network and identity, and an ecosystem that is hard to leave.

Flui isn’t there to compete with what hyperscalers already offer well. The case for using it on a hyperscaler is different: keeping your applications portable across clouds, so the platform on top is not anchored to a single vendor’s proprietary stack.

Do-it-yourself stacks

On any provider you can assemble it yourself: an IaC tool for provisioning, a configuration tool for the host, a packaging tool for workloads, your own GitOps, your own ingress, your own cert-manager, your own DNS automation, your own observability. Each piece is fine in isolation. Keeping them integrated is the work.

Managed PaaS

Hosted application platforms solve the experience problem but they own the runtime. Your applications, your data, and the format you describe them in belong to the platform.

Where Flui sits

Flui is the missing layer: the experience of a managed PaaS, on top of the cloud provider you already use, around an open specification you can take with you. The control plane, the runtime, the manifest spec and every component Flui ships are open source.

What Flui actually does

From the outside, the contract is:

  1. You give Flui a credential for one of the integrated cloud providers (see project status below for the current list).
  2. You run flui env create. About five minutes later the Flui platform is installed on top of that provider and ready to host applications. The individual components it brings — networking, TLS, identity, observability, dashboard, and so on — are covered in their own chapters.
  3. From that moment on, Flui is your single point of control over that environment. Everything inside it — clusters and nodes, networking, identity, certificates, observability, the applications themselves — is managed under one consistent model, driven through the same CLI, dashboard and API.

A note on scope. The cloud providers integrated today are European — an intentional starting point for the project. The platform is built to integrate with any cloud through a provider-agnostic abstraction: each integration exposes the capabilities the underlying provider offers, mapped onto Flui’s common model. Expanding the list of supported providers is on the roadmap.

A note on bring-your-own-server. Flui defines three modes of integration with the underlying infrastructure — Full, Partial and BYOS — covered in How Flui works across providers. BYOS, where you point Flui at a Linux machine you already own, is on the roadmap and not yet shipped. Today the supported path is one of the integrated cloud providers, which provisions and manages the underlying machines for you.

In one paragraph:

A complete platform, not a starter kit. flui env create returns an environment ready for production — every capability you need to deploy and operate applications is wired in from the start, and driven through the same CLI as the applications themselves.

How you drive it

You interact with Flui through three surfaces, all backed by the same API:

  • The Flui CLI — the primary entry point, and the surface this documentation focuses on.
  • The Flui dashboard — a web UI for the same operations.
  • The Flui REST API — exposed by every running control plane.

What Flui deliberately is not

  • Not a fork of Kubernetes. Flui uses K3s upstream and the standard Kubernetes API. Your kubectl works, Helm works, standard manifests work.
  • Not a replacement for the open source ecosystem. Flui builds on top of well-known tools — ingress, certificates, logs, metrics, identity — and integrates them. It does not try to reinvent them.

Status

Flui is in alpha. This documentation tracks behaviour that can be verified in the source or via the CLI, and avoids speculating about features that are not landed.

  • License: AGPL-3.0. Commercial use is allowed; the license obliges you to share source modifications when you offer Flui as a network service to others. The LICENSE file is authoritative.
  • Roadmap and ongoing work: see flui.cloud.

If you want a command-by-command reference, the CLI section is the place. This section is the why, not the how.