Running a periodic eligibility check across thousands of members involves some interesting tradeoffs: batching API calls, building O(n) lookup maps, and handling failures without crashing the whole task.

A contract state decision that started as nested conditionals turned into something that looks a lot like Redux. Here's why that pattern works well beyond the frontend.

Building a Ruby client for the Mindbody API involves more quirks than their documentation suggests. Duplicate clients, phantom contract records, CamelCase everywhere, and a fake credit card to complete a $0 purchase.

A pattern for making background jobs observable: track each attempt as a DB record with status, payload, and email alerts — no external monitoring service required.

A gym's membership migration kept failing intermittently. Here's the three-layer approach that made the integration actually reliable.