Mainframes run because they are reliable. We put APIs and MCP servers on top so modern applications and AI agents can use them — your core stays untouched, the outside world gets access.
Replacing a mainframe costs years, ties up your best people and at best delivers exactly what already ran before. The value is not in the platform but in forty years of embedded domain logic. You don't rewrite that — you make it reachable.
The same transaction becomes usable twice: as a REST API for applications and as an MCP tool for AI agents. One access path, one permission model, one audit trail.
Existing transactions and data access are published as versioned, documented REST interfaces. Web portals, mobile apps and partner systems consume them without knowing anything about the host.
The same functions are exposed as MCP tools. An AI agent can query a balance or check a posting — with the same rights and limits as any other caller.
Which transactions exist, who calls them, which copybooks and data structures hang off them. Without that map any API strategy is guesswork.
COBOL copybooks and host data formats are mapped to JSON. We translate EBCDIC, packed fields and date formats properly instead of passing them through.
OAuth or mTLS on the outside, RACF identities on the inside. Every call maps to a host identity, is logged and is bounded — no blanket access through a shared account.
APIs can make the host cheap or expensive. Caching, rate limits and batched calls keep MIPS cost where it was planned.
Changes in DB2 or VSAM become events via CDC. Downstream systems stay current without polling the host every minute.
When the colleague with the COBOL knowledge retires, the domain logic remains as a documented API — usable by people who have never seen a host.
lines of COBOL rewritten. The proven domain logic stays as it is.
instead of years until the first host function is usable as an API.
access path for applications and AI agents — one permission model, one audit trail.
big-bang risk. Each interface goes live on its own and can be rolled back on its own.
Chosen vendor-neutrally, to fit the problem.
30-min intro call — free.
No standard pitch. I listen, ask the right questions and give an honest assessment — even if we are not the right partner.
