Parallel Verification · adamtylerlynch bundle Build a Parallel Verification (PV) harness — an out-of-band, last-mile integration check that proves a system actually does what it claims by driving its real public interface and then confirming the effects against the real backend through an INDEPENDENT path the code author cannot fake. Use this whenever you are building or reviewing something whose correctness ultimately lands in an external system of record: a REST API that writes to a database, a Terraform provider, a Vault secrets engine, an Okta integration, an IBM z/OS RACF resource, a message queue, an object store, an IAM policy, etc. Trigger on phrases like "verify this end-to-end", "prove it really works", "last-mile verification", "out-of-band check", "did it actually write to the database / state / backend", "black-box integration test", "build a verification harness", or any time unit tests and acceptance tests pass but you still don't trust that the real-world effect happened. Reach for PV precisely when you want a check that does not trust th
