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Migration & Modernization

Complex Data & Legacy Migrations

COBOL, ASP.NET, Oracle, mainframes, warehouses — migrated to modern cloud platforms with row-level parity proofs and zero-downtime cutover.

Start this engagement Read the Reverse SLA

"Whether it's 3M lines of COBOL on the mainframe, a PeopleSoft GL with 20 years of customizations, or a Postgres warehouse moving to Snowflake — the problem is the same: institutional logic nobody fully documented, a hard deadline, and a vendor quoting 3x your budget."

The reality

What you are actually dealing with

  • Legacy talent retiring — COBOL, RPG, ASP.NET, PL/SQL developers are gone or priced at $400/hr
  • 20 years of undocumented customizations, batch dependencies, and tribal knowledge at risk
  • Big SIs quote 5+ years for mainframe modernization and 18 months for warehouse migrations
  • PII columns need classification + transformation under audit before any data moves
  • Cutover risk: production systems used by hundreds of analysts and downstream processes every day
  • Previous migration attempts created partially-migrated systems — worse than the original
Vouchstone countermove

How we ship it

  • Context graph maps the entire legacy landscape first: programs, batch jobs, data flows, business rules, downstream consumers
  • AI agents read COBOL/RPG/ASP.NET/PL-SQL and produce behavioral specs in plain English — your retiring SME validates before they leave
  • Row-level parity proofs at every milestone — not just final cutover
  • Zero-downtime cutover: legacy stays read-only as backup for 30 days post-migration
  • PII discovery + classification + transformation in one pass (Presidio + behavioral)
  • Dashboards and downstream consumers re-pointed automatically with query equivalence proofs
  • Patent-backed Excel reconciliations auditors accept on sight
Reverse SLA

What we owe you when we miss

Most SI contracts only penalise you for falling behind on payment. Our Reverse SLA flips that - when we miss a named milestone, parity threshold, or budget band, we owe you in credits or refund.

Parity

100% row-level / output-byte-equivalence on signed-off scope; discrepancies refund 1:1

Timeline

Named cutover date — slips refund 10% per week past 7-day grace

Budget

Fixed-band pricing — Vouchstone eats overruns inside the band

Downtime

Zero downtime — legacy stays read-only 30 days post-cutover

What you walk away with

Migration Parity Pack + Behavioral Specs

Context graph of legacy landscape, per-program behavioral specs (for legacy code migrations), row-level parity reconciliation workbook, PII classification report, dashboard equivalence proofs, and a signed audit evidence chain.

Side-by-side

Big SI playbook vs. Vouchstone

Big SI

5+ years for mainframe, 18–36 months for warehouse, $40–80M, partner discovers institutional logic on your dime, no parity guarantee

Vouchstone

6 weeks for warehouse migrations, 12–18 months for mainframe/legacy code, 60% of SI cost, context graph + parity proofs at every milestone

Compliance evidence auto-generated

Domains your audit + compliance teams care about

Every action signed to the ledger; every signed action chained into a regulator-ready evidence pack matched to the framework controls below. One-click export, OCSF-formatted for your SIEM.

SOX 404SOC 2 Type 2GDPRHIPAA (if PHI)PCI-DSS (if card data)FedRAMP (gov)

Ready to start?

Five-minute intake. Sixty-second response with a named lead, a draft scope, and a price band. No sales call needed before you see what we propose.