Node-locked licenses, explained

Node-locked is the default model for software sold to people, not server farms. A license works on the device it’s activated on, up to a limit you set. It’s how most desktop apps stop one purchase from running on a hundred machines. Here’s how it works.

What is a node-locked license

A node-locked license is bound to a specific device — the “node.” When a customer activates, the app registers that device, usually via a fingerprint, and the license becomes valid there. Activate on a second machine and it counts against the license’s allowance — say three devices. Past the limit, activation is refused until a seat is freed.

It’s the natural fit when you sell to individuals: a license is a license for their machines, not a key that floats anywhere.

How node-locking works

Three pieces:

• A device fingerprint identifies the machine stably across launches and updates.
• An activation limit sets how many devices a license allows.
• Enforcement registers each device server-side and refuses activations past the limit.

Done well, this is invisible to honest customers and a real wall against casual sharing. Done badly — fingerprints that change on every OS update, limits that lock people out after a reinstall — it generates support tickets. The craft is a stable fingerprint plus an easy way to free a seat when someone gets a new machine.

Node-locked vs floating

Node-locked binds licenses to devices. Floating shares a pool of seats used concurrently, with no fixed device. Node-locked suits apps sold to individuals and small teams; floating suits shared environments — a lab, a classroom, a large org where the same seats rotate across many people. Most indie and pro desktop apps want node-locked.

Node-locked licensing in Keylight

Keylight is node-locked by design. Each license has a device allowance; each activation registers a device server-side and is enforced against that count. The customer’s app carries an Ed25519-signed lease it verifies locally, so it runs offline — while the live device count stays server-side, the one place a limit can actually be enforced.

That binding is also the simplest defense against key sharing: a key pasted onto more machines than it allows simply stops activating. And freeing a seat when a customer switches Macs is one action, so the limit protects revenue without punishing the people who paid.

Plans start at $19/month, with a free tier. Set a device limit, drop in the SDK, ship.