When COBOL changes,
something can go wrong.
The compiler stays silent. Refinery reads the change the way a senior engineer would, and produces the evidence for it.
COBOL is changed
An AI tool, a vendor PTF, or a developer commit modifies a section of code. The compiler accepts it.
Refinery checks the meaning
We compare the original and the new version by examining what the code actually does at runtime.
You get a clear verdict
PASS means the change is safe. FLAGGED means something changed that should not have, with a full report.
Choose an industry
Banking
Banks run settlement, interest, and payment processing on COBOL that has been stable for decades. When AI tools modernise this code, even a tiny change to a calculation can produce wrong numbers, and the compiler will not notice.
What gets missed without Refinery
- A rounding step is removed from an interest calculation. The result is off by a fraction of a penny, invisible in testing, but wrong across millions of transactions.
- An error handler is silently deleted. Under normal conditions nothing breaks. Under edge conditions, the program crashes with no recovery.
- A field type is changed to save memory. Downstream programs that read the same field now get garbled data.
What Refinery catches
- ✓Any change to how a calculation is done, including rounding, precision, and order of operations.
- ✓Removed or bypassed error handling in critical payment paths.
- ✓Field type changes that would break any other program reading the same data.
- ✓A map of every batch job and program that would be affected if the change ships.
A real example
An AI tool rewrites an interest calculation and removes the ROUNDED keyword. The compiler produces clean output. The result is now truncated instead of rounded, a difference that accumulates to millions in incorrect charges over a year.
✓ Refinery flags this before it ships.