Legacy, ERP & Data-Warehouse Migration
Specialist agents grounded in a knowledge graph of source and target schemas do mapping, CDC pipeline building, and UDF conversion deterministically — COBOL, ASP.NET, Oracle, mainframes, and warehouses migrated with row-level parity proofs.
"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."
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
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
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
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.
Big SI playbook vs. Vouchstone
5+ years for mainframe, 18–36 months for warehouse, $40–80M, partner discovers institutional logic on your dime, no parity guarantee
6 weeks for warehouse migrations, 12–18 months for mainframe/legacy code, 60% of SI cost, context graph + parity proofs at every milestone
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.
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.
Other flagship engagements
Internal Knowledge Copilots
Narrow, team-specific copilots grounded in tribal knowledge — not one generalist bot that knows a little about everything. Built on a living context graph of your docs, code, contracts, and conversations.
RPA Replacement in Finance Ops
AP invoice automation and cost anomaly detection. Every approval checked against exact graph facts — vendor, contract clause, policy — and written as a signed workflow trace, not a brittle screen-scraping bot.
Compliance & Audit Evidence Automation
SOC 2 evidence collection, PII classification scanning. Controls mapped to policies; every audit run is signed and traceable back to source.