welldun is where I build and document practical software + AI infrastructure — multi-tenant platforms, voice agents, email pipelines, and the systems behind them.https://blog.welldun.ai/en-ushttps://blog.welldun.ai/posts/00-series-intro/https://blog.welldun.ai/posts/00-series-intro/Why we're building a 'define-your-own-data' platform — and what this series will cover.Fri, 26 Jun 2026 00:00:00 GMTDrafting Tableintroarchitecturehttps://blog.welldun.ai/posts/01-the-architecture-bet/https://blog.welldun.ai/posts/01-the-architecture-bet/The core bet: a registry as source of truth, JSON for storage, and generated SQL views on top.Fri, 26 Jun 2026 00:00:00 GMTDrafting Tablearchitecturepostgresjsonbhttps://blog.welldun.ai/posts/02-tenant-isolation-rls/https://blog.welldun.ai/posts/02-tenant-isolation-rls/How Postgres makes data isolation a property of the database — and the view gotcha that nearly leaked everything.Fri, 26 Jun 2026 00:00:00 GMTDrafting Tablesecuritypostgresmulti-tenancyhttps://blog.welldun.ai/posts/03-constraints-and-relationships-on-json/https://blog.welldun.ai/posts/03-constraints-and-relationships-on-json/How to enforce real constraints and relationships when the data lives in a JSON blob and the schema was invented by a user.Fri, 26 Jun 2026 00:00:00 GMTDrafting Tablepostgresconstraintsjsonbhttps://blog.welldun.ai/posts/04-what-load-testing-taught-us/https://blog.welldun.ai/posts/04-what-load-testing-taught-us/A bottleneck we couldn't see, a 400ms query that became 0.3ms, and why 'a lot of data' isn't the same as 'slow.'Fri, 26 Jun 2026 00:00:00 GMTDrafting Tableperformancepostgresload-testing