Keylight vs Keyforge — the SDK-first alternative

You need licensing and you’ve found Keyforge and Keylight. Both do the job — license keys, offline checks, no backend to run. The difference is one line. Keyforge is a REST API for every platform, wired by you. Keylight ships finished SDKs — Swift, Rust, JavaScript — with the licensing glue and Stripe already in. Pick on that.

What Keyforge gets right

Keyforge is good. For an indie dev who wants license keys without standing up a backend, it’s a clean choice. The public REST API needs no key, so you call it from any language. Stripe, Polar, and Lemon Squeezy all map payments to keys for you. Offline checks run on signed JWTs. There are real docs for macOS and Tauri.

Need a stack without a Keylight SDK yet — Python, Go, C# — and a plain API you call from any language is the easy fit. Keyforge leans into that.

Where Keylight is different

The split is what happens inside the app.

Keyforge hands you an endpoint. Everything after — storing the lease, checking expiry, the trial countdown, what to show on launch — is yours to write. Fine for a web backend. For a desktop app it means rebuilding the same licensing glue every paid app ends up writing — which is exactly what the Keylight SDKs hand you, done.

Keylight ships that part. The Swift SDK is a state machine. Call checkOnLaunch(), switch on the result:

await licensing.checkOnLaunch()

switch licensing.state {
case .licensed:
    enablePaidFeatures()
case .trial(let daysLeft):
    showTrialBanner(daysLeft: daysLeft)
case .expired:
    showRenewalPrompt()
case .invalid:
    showActivationSheet()
}

That’s the integration. No license state to track yourself.

Offline checks run on Ed25519-signed leases. Your app holds the public key and verifies locally — no network on launch. Keyforge’s JWTs do the same job. The difference that matters: Keylight signs feature flags into the lease, so you gate Pro features offline without another call.

Payments: a Stripe charge mints the license. Keylight catches the webhook, you write nothing. Other providers connect by webhook too — Stripe is just the path that’s already done.

When Keyforge is the better pick

Be honest about it. Keyforge reaches languages Keylight has no SDK for yet — Python, Go, C#, a native Windows or Linux build — and a plain REST API you call in your own language is the easy fit there. Same if Polar or Lemon Squeezy is your main processor — Keyforge integrates them directly; with Keylight that’s a webhook.

Keylight is Swift-first, not Apple-only — Rust and JavaScript ship too. On the stacks it covers, a done-for-you SDK is the point, not a ceiling.

Where Keylight fits

Building a Mac or Swift app and want licensing that drops in? That’s Keylight. The Swift SDK handles activation, offline checks, trials, expiry. Stripe mints the license on payment. Feature flags ride in the lease, readable offline. Multi-product and multi-tenant are built in, not bolted on.

The win isn’t setup time — both set up fast. It’s never writing the licensing state machine every paid Mac app needs.

Plans start at $19/month, with a free tier. Test the whole Stripe-to-app flow before you pay.