.tip

Jun 28, 2026 · one of the small things

A cron job that stops running is silent, so give it a heartbeat

A job that fails logs an error. A job that never starts, because the scheduler died or the config changed, logs nothing, and nobody notices for a month.

run-nightly-report && curl -fsS https://heartbeats.example.com/ping/nightly-report

The monitor alerts when the ping hasn't arrived by the expected time, so a missing signal becomes a signal of its own.

observabilityoperations

~/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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