#infrastructure
A collection of 5 technical articles about #infrastructure.
100% coverage, and it still did not run
A feature was completely dead in production while 178 tests were green and coverage held at 100%. Tests measure lines that ran, not the path that ships.
Cut the context, keep the audit trail
Compaction deletes nothing. It only shadows a range on the surface sent to the model, records exactly which range, and leaves the original in the log for later.
The log is the source, not a copy
Everything the model sees must be in the log first. Context is never stored beside it — it is derived, and that is the difference between a source and a copy.
The same loop, different seams
Every harness has a log, a tool registry, a context budget and a permission layer. They differ in which of those you may replace — I read four to answer.
Where a harness begins
The loop is only a coordinator. Four parts turn it into a harness: a durable log, a tool registry, a context budget, and a permission layer, all four pluggable.