* [Lago v1.47.0](https://github.com/getlago/lago) – Programmable API for usage-based billing designed for product-led SaaS.

* [Flexprice 2.1.12](https://github.com/flexprice/flexprice) – Usage metering and billing infrastructure designed for AI companies to streamline pricing models and track usage.

* [Velobase Harness v0.1.0](https://github.com/velobase/velobase-harness) – AI SaaS framework providing monetization, usage-based billing, affiliate engine, ad attribution, and anti-abuse guardrails.

* [LedgerSMB 1.13.6](https://github.com/ledgersmb/LedgerSMB) – Web-based double-entry accounting and ERP system for small and medium businesses.

* [PayKit v0.0.6](https://github.com/getpaykit/paykit) – Embedded TypeScript billing framework that defines code-first plans, syncs with Stripe, gates features, and tracks usage.

* [YETI 1.15.11](https://github.com/yeti-switch/yeti-web) – Admin interface for managing SIP SBC with billing and multiple database support.