Backed bybased.
collective

Verification infrastructure
for consequential software.

Proving mission-critical code still behaves correctly after an AI tool rewrites it, with evidence a regulator can inspect.

Product preview: Refinery flags an AI change to INTEREST-CALC that moved the overdraft threshold from 5,000 to 9,000, and asks a person to accept it or return it to the developer.

Product preview. Example change, not real customer data.

AI changes are outrunning review.

An AI tool can rewrite a COBOL program in minutes, and checking what it actually changed is still one person reading it line by line.

Unverified change
  • nowAI rewrote INTCALC.cbl
  • PR #482"Looks fine to me"
  • Line 213Threshold moved, unnoticed
  • CHG0041233"Who approved this?"
How it works

Follow one change
across your whole estate.

Product preview, in eight steps: an AI tool edits INTEREST-CALC; Refinery maps the programs, copybooks, datasets and batch jobs linked to it; it maps everything the change reaches, four programs and two batch jobs, and checks the changed program; it finds that line 213 moved the overdraft threshold from 5,000 to 9,000, so a balance of 5,001 is charged 25.00 before and 0.00 after; Explain answers in plain words; the change manager accepts it as intended and signs; the certificate lands on the pull request and the change ticket; the next change to INTEREST-CALC arrives with that decision, who made it and why.

01 · The change

Your AI tool changes the code.

Any tool, or any person, edits one program. It compiles, but other programs and nightly jobs depend on it, and nobody has checked what it now does.

02 · The estate

Refinery already knows your estate.

It reads the programs, copybooks and batch jobs in your source, and how they connect, so it sees a change in context, the way your most experienced engineer would.

03 · The reach

It shows everything the change reaches.

Not just the edited line: the programs that call it, the copybooks and data it shares, and the jobs downstream, so you know what to retest before it ships.

04 · The finding

It finds the one line that matters.

Line 213 moved a threshold from 5,000 to 9,000. Run both versions on a balance of 5,001 and the charge drops from 25.00 to nothing.

05 · The answer

And explains it to whoever decides.

Ask in plain words and get a plain answer, so the person deciding does not need an engineer beside them.

06 · The decision

A named person signs.

They accept the change as intended or send it back. Either way the decision is recorded under their name, and an accepted change gets a signed certificate.

07 · The record

The evidence files itself.

The certificate and the evidence pack land on the pull request and the change ticket, ready for the change board and for audit.

08 · The memory

And it gets better with every change.

Every accepted change is remembered, with who accepted it and why. The next change to that program arrives with what was decided before.

Product preview. Example change, not real customer data.

Product preview. Example change, not real customer data.

What you get

One framework for AI changes
to legacy systems.

Engineering, risk, compliance and the business work from the same evidence, on the same change.

One change
PAYROLL.cblPassed
PR #479CHG0041219
Changed by
GitHub Copilot
Checked by
Refinery
Signed by
Jordan Lee
Developer

A verdict in minutes, in the pipeline.

Runs next to your build and tests, on every change the AI makes.

Buildpassed
Unit testspassed
Refinery verdictCheckingPassed
Change board

Evidence on the change ticket. A clean pass goes through as a standard change.

The certificate and evidence pack sit on the ticket, so the board decides on facts.

CHG0041219Standard change
Certificate attached
Evidence pack attached
Risk team

One signed report over every AI change.

Every change, every check and every sign-off in one place, ready for audit.

ChangePR #479
Signed byJordan Lee
Signature verified
Head of mainframe

AI changes shipped safely, and measured.

See how much AI work reaches production safely, and where people still step in.

AI changes shipped safely
Versus today

Manual review, against Refinery.

The same release decision, without the wait or the guesswork.

Manual review compared with Refinery
AspectManual review todayWith Refinery
TimeDays to weeks of specialist reviewMinutes
CoverageA sample gets a close lookEvery change checked
RecordA tick in a ticketA signed certificate anyone can verify
AssuranceTrust the reviewerProof and evidence a regulator can inspect
Your codeSent out to review toolsNothing leaves the bank
Why Refinery

Everyone checks their own homework.
Now someone else can.

The platforms rewriting your COBOL also supply the evidence that the rewrite was safe. They test well, and they test themselves.

  1. 01 / 04

    Independent of the tool that made the change

    It checks code written by any AI tool or person, and has no stake in the answer.

    Product names and logos are trademarks of their owners. Refinery is not affiliated with them.
  2. 02 / 04

    Context across the estate

    It maps the programs and jobs a change reaches, so you retest what actually changed.

  3. 03 / 04

    Proof, not sampling

    It proves the calculations match for every value the fields can hold, or hands you an input that breaks them.

  4. 04 / 04

    Better with every change

    Every accepted change is remembered with its reason, so the next change to that program arrives with what was decided before, and why.

See how that compares to AI migrations, code gates and manual review →

Governance portal

One place to see
every change.

Every change, every check, and every sign-off in a single view your risk team can read without an engineer sitting next to them.

Portfolio

Every change, in one view.

Verdicts and sign-offs, together with the code they cover.

5 example changes
ProgramChanged byVerdictSigned byDate
INTCALC.cblwatsonx Code Assistant for ZAccepted as intendedMaya Chen
PAYROLL.cblGitHub CopilotPassedJordan Lee
LOAN-RATE.cblPriya ShahFlaggedNot signed
STATEMENT.cblCursorPassedEva Brooks
BATCH-POST.cblSamir AliPassedOlivia Price

Product preview. Example changes, not real customer data.

The journey so far

Backed by the ecosystems
shaping what comes next.

Refinery has grown through programmes and communities spanning mainframe technology, cyber resilience and ambitious company-building.

Built with ecosystem support01

DiSH Accelerator

Selected for the Manchester programme helping security-focused startups build stronger, more resilient companies.

BARCLAYS EAGLE LABSPLEXALTHE UNIVERSITY OF MANCHESTERLANCASTER UNIVERSITY
Deep mainframe expertise02

IBM Z ScaleUp

Accepted into the cohort for startups building on IBM Z and enterprise-grade infrastructure.

IBM Z
Founder community03

Based Collective

Backed by the European founder collective and selected for the first OpenAI Hacker House in London.

BASEDOPENAI HACKER HOUSE

See Refinery run
on your code.

Book a call →