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Subscription Lifecycle Engine

The complete system record. Choose the proof lens that fits your role.

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Choose The Proof Lens

One system record, three reader paths.

Feature-frozen3-act recordGitHub available
Business proofFounder / operator

Turning Stripe Payment Failures Into Recovered Revenue

Five percent of subscription charges fail and most become involuntary churn. A Stripe-backed state machine recovers €7,200 a year on 500 subscribers.

System FlowData ModelArchitecture LayersDecision Log
Open business proof8 min read
Architecture proofCTO / architect

Architectural Brief: Subscription Lifecycle Engine

Eight subscription states with 15 valid transitions enforced in Elixir. OTP supervisors restart crashed processors; Oban handles retries on Postgres.

System TopologyInfrastructure DecisionsConstraintsDecision Log
Open architecture proof6 min read
Technical proofSenior engineer

Stripe Said Past Due. The State Machine Said No. Both Were Right.

Stripe sent past_due on a paused subscription. The local state machine rejected the whole payload and lost everything downstream of the status field.

Code SampleFailureConstraint
Open technical proof8 min read

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