Sovereign & Open-Source
Subscription Engine
Subkit is an early open-source foundation for portable subscription infrastructure, designed so teams can inspect, operate, and extend their own deployment.
Why We Are Building Subkit
Mobile subscription infrastructure is commonly delivered as a managed service. That is convenient, but it can make portability, inspection, and independent operation harder for teams that need those properties.
Subscription systems often require teams to trust infrastructure they cannot inspect or operate themselves. We believe critical transaction pipelines should be portable, auditable, and available as open-source building blocks.
Our mission is simple: to democratize in-app monetization by building an open-source standard for mobile subscriptions.
Funding Intent & Public-Interest Direction
Subkit has submitted a European open-source funding application and is awaiting review. An application does not imply selection, funding, endorsement, or support by NGI. Its public-interest goals overlap with themes promoted by European open-internet programmes:
- ✓Human-Centric: Privacy-aware design and meaningful operator control.
- ✓Open-Source Centered: Inspectable code, reusable interfaces, and portable deployment.
- ✓Portable & Resilient: Self-hostable models that can support an operator's residency and continuity strategy.
Our Core Pillars
Designed around trust, agility, and performance.
No Data Vendor Lock-in
The self-hosted direction keeps application data in infrastructure selected by the operator. Portability and migration tooling are goals; they are not yet production guarantees.
Auditability & Transparency
Public source allows developers and reviewers to inspect Subkit's implementation and report security concerns. Formal third-party audits have not yet been completed.
Data-Control by Design
Portable deployment can help organizations choose where data is processed. Self-hosting does not itself guarantee GDPR compliance; operators remain responsible for security, retention, lawful processing, contracts, and data-subject rights.
Green IT & Performance
Planned SDKs will target small, documented dependency surfaces and measurable startup behavior. No performance or environmental-impact claim will be made before implementations are benchmarked.
Open Core & Federation
A future research direction may explore interoperable Subkit installations. Federation is not part of the current product and would require a defined trust, identity, privacy, and threat model.
Planned Public SDKs
Swift, Kotlin, Flutter, and React Native are planned targets. Implementations, package footprints, compatibility, and performance will be published only after they are measured.
Portable, Explicit, and Developer-Centric
The current architecture direction and its pre-alpha boundaries.
Portable Self-Hosted Runtime
Run the Core API directly with Node.js and PostgreSQL or use the OCI-compatible image and Compose reference deployment. The Event Inbox also has libSQL-compatible and PostgreSQL adapters. Production scaling guidance is not yet published.
Planned SDK Clients
Planned iOS, Android, Flutter, and React Native clients built against an explicit public contract.
SUPPORT THE INITIATIVE
Review the current foundation, open an issue, or contribute on GitHub.
Let's Build a More Open Internet
Interested in open-source subscription infrastructure or European digital-commons funding? We welcome technical feedback and collaboration.