License Key System Launch Checklist
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A pre-launch checklist covering key generation, validation, activation limits, lifecycle events, protection, and support tooling for a digital product's licensing system.

[ ] The licensing model (perpetual, subscription, trial, seat-based, device-based, or a hybrid) is written down along with why it matches how the product is sold.
[ ] Each license record carries its type, expiry or renewal date, activation allowance, and feature entitlements as data fields, not as logic compiled into the application.
[ ] Keys are generated from a cryptographically secure random source, never from timestamps, sequential counters, or anything derived from customer data.
[ ] The key format uses grouped alphanumeric characters, drops ambiguous characters such as the letter O and the digit zero, carries a product prefix, and includes a checksum that catches typos before any network request.
[ ] A server-side record exists for every issued key and is treated as the single source of truth about which keys are valid.
[ ] If any customers need offline or air-gapped use, a signed license file path is planned and the reissue process for changes is documented.
[ ] The validation endpoint checks that the key exists, is not revoked, has not expired, and has an activation slot available before returning a yes.
[ ] Validation responses are signed so a modified client cannot simply pretend the server approved the license.
[ ] The app caches the entitlement and rechecks quietly in the background instead of making a blocking request on every launch.
[ ] An offline grace period measured in days is defined, and the behavior after it ends is a reminder or read-only state, not a silent lockout.
[ ] The activation limit for a single-user license tolerates normal life, such as a laptop plus a desktop, and old activations can be released.
[ ] Customers can deactivate a device themselves from inside the app or a customer portal without emailing support.
[ ] Lifecycle statuses are defined (for example active, expired, suspended, revoked) and every business event is mapped to a transition between them.
[ ] A refund in the payment system automatically revokes the license through a webhook or a scheduled reconciliation, with no manual step.
[ ] A successful renewal payment automatically moves an expired license back to active and pushes the date forward.
[ ] Upgrades change the entitlements on the existing key rather than issuing a second key the customer has to juggle.
[ ] Every validation failure message explains what happened and what to do next in plain language, with a link to renew, deactivate, or find the key.
[ ] Rate limiting is enabled on the validation endpoint to stop brute-force key guessing.
[ ] The support team can look up a license by key or email and see its status, activations, and history in one place.
[ ] Key delivery is tested end to end: purchase, key arrival by email, paste into the app, first activation, second device.
[ ] Expected validation call volume has been estimated for the installed base, and the plan tier or server is sized for the peak hour rather than the daily average.
[ ] Every license record can be exported if the product ever moves to a different provider or an in-house system.
[ ] Signing key rotation and public key distribution are documented, including what happens to keys signed before a rotation.
[ ] The build-versus-buy decision has been made deliberately, with first-year and three-year costs of both paths put side by side.