License

Free under GPL-3.0, or commercial. Pick the path that matches how you ship.

Where do you fit?

Pick the situation closest to yours. Every reader sees the full page below — this is a shortcut, not a gate.

I’m building an open-source project
GPL-3.0 covers you, free. Use, modify, and ship AudioUI as long as your application is also under GPL-3.0 (or a compatible license).
I’m building internal tools or prototyping
GPL-3.0’s obligations apply only when you distribute. Internal company tools, research, learning, and pre-release work are free, no caveats.
I’m shipping a commercial app
A commercial license fits if you don’t want to open-source your application. Pricing scales with your organisation’s annual revenue, not seat count.
I’m reviewing for procurement or legal
Direct links to the formal documents, the support model, and the dispute clauses are below. The Evolution Framework section explains how component licensing can change over time.
I’m just exploring
Most readers land on either the free path (GPL-3.0) or a small annual commercial license. The next section explains the choice in plain terms.

Two ways to use AudioUI

There’s a clear fork: free under GPL-3.0, or commercial. The deciding factor is how you ship.

Free, under GPL-3.0

The GPL-3.0 path is free. It applies if:

  • You’re shipping your application’s source code under GPL-3.0 (or a compatible license).
  • You’re not distributing your application at all. Internal company tools, prototypes, research, learning, and pre-release development all fall here.

If you ship your app under GPL-3.0, the source you provide is your full application’s source, not just AudioUI’s. AudioUI is a React component library that runs in your users’ browsers, so any application you ship that uses it counts as distribution: desktop apps (Electron, Tauri), web applications, plugins with web UIs.

Commercial license

You need a commercial license if you want to ship your application without releasing its source code under GPL-3.0.

A commercial license removes the GPL-3.0 source-availability obligation and replaces it with commercial terms. You also get an SLA, priority bug fixes, private support channels, and additional weight on feature votes. Pricing scales with your organisation’s annual revenue, not with seat count or developer count. See pricing for tiers.

Which one am I?

You ship…License
Open-source app under GPL-3.0 (or compatible)Free under GPL-3.0
Internal tools only (no external distribution)Free under GPL-3.0
Prototypes, research, learningFree under GPL-3.0
Closed-source applicationCommercial
Plugin or SDK distributed without sourceCommercial

What’s included with a commercial license

Three buckets: rights you gain, support you can rely on, influence on direction.

Rights
  • Perpetual license to versions released during your subscription term
  • No GPL-3.0 obligations for your distributed application
  • Modifications to AudioUI can be kept private
  • Use across your entire organisation, no seat limits
Support
  • SLA-guaranteed response times for critical issues
  • Priority bug fixes on GitHub Issues
  • Private Discord channels available on request for sensitive topics
  • Verified-customer status linking your GitHub and Discord accounts
Influence
  • Additional weight on feature votes in GitHub Discussions
  • Direct input into roadmap planning
  • Voting is advisory; all roadmap decisions remain at Cutoff’s discretion

What you can and can’t build

The simple rule: build products for users, freely. Don’t build a competing developer framework.

What you can build

Allowed under both the GPL-3.0 path (with GPL-3.0 source obligations) and the commercial license (without).

  • DAWs (digital audio workstations)
  • VST/AU plugin suites
  • Music streaming services with audio processing
  • Podcast editing apps
  • Online DAWs (browser-based music production)
  • Music education software
  • MIDI controller apps
  • Audio analysis tools
  • Game audio systems
  • Proprietary plugins or extensions for your own applications

What you can’t build

These competitive-use restrictions apply to both license tracks.

  • A competing audio UI component library or framework targeted at developers
  • A repackaging of AudioUI as a development toolkit
  • A fork of AudioUI sold as a premium product

Gray area? If your software is primarily used by developers to build their own audio software, it may compete; if it’s used by end users to make, edit, or consume audio, it’s allowed. Email legal@tylium.io with your use case if you’re unsure.

Why per-revenue, not per-seat

One organisation-wide license per tier. We don’t count developers, designers, or AI agents.

The commercial license is priced against your organisation’s annual revenue. A two-person studio at €200k pays the Indie tier; a 50-person studio at €5M pays the Enterprise tier. Both get the same product.

What this means concretely:

  • Hire ten more developers and your bill doesn’t change. Add fifty contractors: same.
  • Use AI coding assistants across your team without each agent costing you a seat.
  • Per-developer cost goes down as your team grows. At Enterprise tier, a 50-person team works out to roughly €80 per developer per year.
  • The price you pay reflects your business’s stage, not the size of its engineering org.

We chose this model because we want our pricing to follow your success, not punish it. Per-seat pricing rewards small teams, then ramps up exactly when growth or AI adoption should be cheap; we’d rather scale with the revenue your product creates.

What happens when you stop paying

Your license to versions released during your term is perpetual. No vendor lock-in, no rugging.

  • Every AudioUI version released while you were a customer stays licensed to you, forever.
  • You can keep using, modifying, and shipping applications based on those versions without ever renewing.
  • Renewing keeps you on the latest releases, with continued support and SLA coverage.
  • If you stop renewing, you keep what you had. You can transition to the GPL-3.0 track on future versions if you want.

The Evolution Framework

Components can become more permissively licensed over time, never more restrictive.

The license permits AudioUI components to be released under more permissive licenses over time: from GPL-3.0 to MPL-2.0 (file-level copyleft), or directly to MIT and Apache-2.0 (fully permissive).

Each transition is at the Licensor’s discretion, not a fixed schedule. When we exercise that permission for a component, every commercial licensee inherits the new rights automatically. The direction is one-way: components don’t become more restrictive.

The intent is that as AudioUI matures and the commercial track sustains the project, more of the codebase becomes freely available to everyone, without abandoning the customers who paid to make that maturity possible.

Frequently asked questions

Common questions about using and buying AudioUI.

Using AudioUI

Buying & renewing

Compliance & support

Evolution Framework