
Your tests are green. Your invoices are wrong. An upstream team changes a contract. A status value that used to be PENDING becomes AWAITING_PAYMENT. Nothing crashes. No alert fires. Existing tests still pass. But downstream, the billing service only knows about PENDING, so unpaid orders quietly bypass validation and get invoiced anyway. This is contract drift. It is one of the most expensive failures in distributed systems because the system keeps running while producing the wrong result. SyncSnitch is a human gated IBM Bob 2.0 agent that catches contract drift before rollout. When an upstream pull request changes a REST API, a gRPC contract, or a database migration, SyncSnitch launches a nine step investigation. First, it detects drift across all three contract surfaces. It then traces the change to every downstream file, endpoint, and database query that actually depends on it. Next, it identifies whether the impact is loud, such as a validation error or service failure, or silent, where business logic continues running incorrectly. IBM Bob 2.0 subagents then investigate the affected code, generate a backward compatible tolerant reader adapter, and prepare a fix. The fix is verified against both the old and new contract versions using deterministic checks, test fixtures, and Docker based validation. Most importantly, the AI never decides whether its own work is correct. Six verification stages determine pass or fail. The AI investigates and writes the fix. Deterministic checks validate the result. A human always reviews and approves before any pull request is created. Current tools stop at detection. They can tell you that a contract changed, but engineers still have to manually find every consumer, trace the impact across repositories, write compatibility code, and prove the fix works. SyncSnitch automates that entire workflow while keeping humans in control. In our live case, a single upstream pull request introduces breaking changes across REST, gRPC, and database contracts. SyncSnitch identifies every real downstream impact, correctly ignores a harmless change, generates the required adapters, and produces a compatibility matrix built from real HTTP calls. The system goes from broken to compatible before the upstream change ever reaches production. Built with IBM Bob 2.0, SyncSnitch is designed for backend and platform teams managing multiple services where contract changes happen constantly and manual tracing no longer scales. Every breaking change leaves fingerprints. Catch it. Prove it. Sign it.
27 Sep 2026