.tip

Jul 28, 2026 · one of the small things

A builder per entity, with sensible defaults

Test setup that builds a full Order with twelve fields every time is noise, and the one field the test cares about gets lost in it.

const order = buildOrder({ status: "shipped" }); // everything else valid and boring

The builder owns the defaults. When the entity gets a new required field, you change one builder instead of two hundred tests.

testing

~/tips/today — 2026-10-19

~cat tips/today

Never build an index on a live table without CONCURRENTLY

postgresqlmigrations

A plain CREATE INDEX takes a lock that blocks every write to the table for the whole build. On a big table that means minutes of outage that look like a hung app.

CREATE INDEX CONCURRENTLY orders_customer_idx ON orders (customer_id);

It's slower and can't run inside a transaction, so you'll have to tell your migration tool. If it fails halfway, it leaves an invalid index behind, so check pg_index.indisvalid and drop it before you retry.

↵ open y yesterday l ls /tips

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