Open Source Feature Flags

If you are looking for open source feature flags, the core requirement is usually not just “can this toggle a boolean?” It is more often:

• can we run it ourselves?
• can we avoid SaaS lock-in?
• can we keep frontend and backend flag reads under control?
• can we add kill switches without adding another hosted dependency?
• can we use a standard interface like OpenFeature?

Nona is built for that class of problem.

Why teams look for open source feature flags

Common reasons are self-hosting, control over infrastructure and data, a simpler deployment model, keeping feature flags and remote config in one system, and avoiding tight coupling to a hosted platform.

What Nona provides

Nona supports feature flags through its core config-entry model.

A typical flag is:

• key: Features:Checkout
• value: true or false
• content type: boolean
• scope: client, server, or all

That means you can use Nona for:

• frontend feature flags
• mobile feature flags
• backend feature flags
• kill switches
• environment-specific enablement

How to try it quickly

In admin:

1. open Projects
2. create or open the project
3. create staging and production
4. add a boolean parameter such as Features:Checkout
5. create an API key

With the CLI:

nona entries set \
  --project storefront \
  --environment production \
  --key Features:Checkout \
  --value true \
  --scope client \
  --content-type boolean

Why this model works

Nona keeps feature flags inside the same system as runtime configuration.

That gives you:

• one project and environment model
• one API key model
• one audit path
• one rollback path
• one deployment surface

For many teams, that is more valuable than a bigger but more complex flag platform.

Open source and self-hosted

Nona is open source, self-hosted, Docker-first, accessible through plain HTTP, usable with official JavaScript and .NET clients, and integrated with OpenFeature. That makes it a strong fit for teams that want self-hosted feature flags without committing to a large proprietary control plane.

Where Nona fits best

Nona is strongest when your team wants reliable boolean flags, kill switches, simple release gates, backend and frontend separation through scope, OpenFeature compatibility, and feature flags with remote config in the same product.

What Nona is not trying to be

Nona should not be described as a giant experimentation suite.

The current repo points to a simpler and more focused model:

• feature flags
• runtime config
• scopes
• history and rollback
• migration tooling

It should also be described plainly:

• no built-in per-user targeting
• no runtime segmentation or cohort evaluation
• no percentage rollout engine

That is often exactly what teams want when they search for open source feature flags. They want control and simplicity, not more platform sprawl.

Next practical step

If this is the page that matches your search intent, continue with:

1. Get started
2. Kill switches
3. OpenFeature

FAQ

Is Nona really open source?

Yes.

Nona is open source and self-hosted, which is part of why it fits teams looking for infrastructure control instead of a hosted flag platform.

Can I use Nona just for feature flags?

Yes.

Many teams start with boolean flags and kill switches first, then expand into broader runtime configuration later.

Does Nona support backend and frontend flags?

Yes.

The scope model lets you separate client, server, and shared reads so the same system can support frontend, mobile, and backend use cases.

Does Nona support targeting or percentage rollout?

No.

Nona is not trying to be a LaunchDarkly-style targeting engine. Flag reads are not evaluated against user context, segments, or percentage rules.

When is Nona a better fit than a larger flag platform?

Nona is usually the better fit when you want self-hosting, simpler operations, and one product for feature flags and remote config without committing to a larger hosted control plane.

Related docs

• Feature flags
• What are feature flags?
• Kill switches
• OpenFeature
• Client vs server scope