Founder Built Custom Licensing SDK After Paddle, Gumroad Failed Offline Desktop Apps

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A developer building a paid desktop app found that Stripe handles payments but provides no licensing features, prompting a search for third-party solutions. Platforms like Paddle, Gumroad, and Lemon Squeezy were evaluated but rejected due to higher fees, reliance on online-only license validation, and vendor lock-in risks. The core technical concern was that server-dependent license checks fail paying customers who are offline and can be bypassed by blocking network access, whereas cryptographic local verification was needed. The developer's caution proved warranted when Paddle announced it was winding down Paddle Classic — the version that included built-in license keys and a Mac SDK — leaving developers on that platform forced to migrate. This led the founder to build Keylight, an in-house licensing SDK designed for offline-capable, cryptographically verifiable license keys that remain independent of any third-party platform.

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