Signal LynxEd25519-signed proof for when the internet ghosts you — and your users still expect the software to work.
The internet is a liar. It is amazing right up until the moment your customer is on a job site, on a plane, in a lab, in a secure environment, or in a hotel where the WiFi password looks like a missile serial number.
There is also the scenario nobody plans for: your backend goes down. Your VPS is rebooting. A dependency breaks. A cert expires. Some gremlin shows up at 2 a.m. and now you are in incident mode. Your customers do not care. They still want the software to work.
Offline tokens exist because reality exists.
What an offline token is (without the crypto sermon)
An offline token is a small blob of data that says: this license is valid until this time, with these entitlements, under these limits. That token is signed by your server.
- Your server holds a private signing key.
- Your app holds the public verification key.
- Your app verifies the token locally.
- If the token is altered, verification fails. If it is expired, it fails. If it is valid, green light.
No internet required. No constant calls back to base.
Why Ed25519 is the right tool for this job
Ed25519 is fast, compact, and built for real deployments. Verification is quick. Keys are small. Tokens stay lightweight. Licensing should never feel heavy.
How this fits into your product (the honest part)
Key Commander can issue the tokens, but your product still needs to know how to use them. That means wiring in a local verification step, and falling back to that verification when the network or the backend is unavailable.
Real-world wins for builders
- Stops punishing legitimate users for imperfect connectivity.
- Keeps tools running in remote environments and supports air-gapped deployments.
- Reduces licensing-related support tickets.
- Protects renewals by keeping customers productive.
- Helps with practical anti-piracy (tampering fails verification).
Closing thoughts from the night desk
Easy mental model: the server stamps a passport. The app checks the stamp. Fake stamp, denied. No internet, still valid until the stamp expires. Backend down, still valid until the stamp expires. Customer stays productive while you fix your mess.
That is offline licensing done the sane way.