Source-available instead of open source — why Lumio uses the FSL
Lumio's source code is public, but not classic open source. We explain honestly what the Functional Source License means — and what you're allowed to do with it.
Lumio’s complete source code is openly viewable on our Git server. Still, we deliberately call Lumio not “open source” but “source-available”. This article explains the difference — and why we decided on it.
What changed
Lumio used to be under the AGPL-3.0, a classic open-source license. We now use the Functional Source License (FSL). The reason is simple: the AGPL doesn’t protect against someone taking Lumio, building a competing cloud gallery from it and offering it cheaper. It only requires that provider to also disclose their code — it doesn’t prevent the business model.
That’s exactly what we wanted to solve differently, without hiding the code.
What the FSL permits
The FSL permits almost everything you’d expect:
- Use privately — without restriction.
- Self-host as a pro — on your own server, commercially for your studio.
- Operate as an agency — host Lumio as part of the service for your clients.
- Modify the code — fork, extend, build your own features.
The only restriction: you may not build a competing, hosted SaaS product from Lumio that offers the same functionality to third parties as a service. So anyone who uses Lumio as a tool for their own work is always on the safe side — whether hobby, pro or agency.
The twist: after two years it becomes open source
The special thing about the FSL: it’s time-limited. Two years after the release of each version, that exact version is automatically placed under the Apache-2.0 license — i.e. true, unrestricted open source. The restriction therefore always applies only to the most recent two years’ worth of versions.
That gives us protection against direct competition in the window where it counts, and still gives the community the long-term guarantee that the code becomes permanently free.
Why we honestly say “source-available”
There’s a trend of marketing restricted licenses as “open source” anyway. That’s called “open washing”, and we consider it dishonest. “Open source” has a clear meaning defined by the Open Source Initiative — and the FSL doesn’t meet it in the first two years.
That’s why we say what’s true: source-available. The code is open, auditable and self-hostable. But it’s just not unrestricted open source, and we don’t hide that.
What this means for you in practice
For the vast majority of users, nothing changes. If you want to self-host Lumio for your studio or your clients, you may do so without a license fee, without conditions, without a disclosure obligation. You can read, audit and modify the code. You aren’t dependent on us — if Lumio disappears as a cloud provider, your instance keeps running.
The only one the FSL slows down is whoever wants to compete against our cloud with our own code. And we consider that fair.
If you have questions about the license or a scenario that falls into a gray area, just write to us — we’ll clarify it transparently.