Plugs into the gear you already have. No rip-and-replace.
Perslis drives old DOS and Windows software from its own buttons and fields, connects to mainframes through the ways in they already have, and pulls old data out with a receipt for every step. A COBOL answer is proven by a compiler or refused. Nothing gets ripped out, and nothing waits on a new program of record.
Nobody gets to start over. The GAO found a Defense Department system that coordinates the operational functions of the nation's nuclear forces running on an IBM Series/1 — "a 1970s computing system" — with 8-inch floppy disks. About 75 percent of the federal IT budget for fiscal year 2015 went to operating and maintaining existing systems (GAO-16-468, Information Technology: Federal Agencies Need to Address Aging Legacy Systems, May 25, 2016). Anything new in your unit has to work with what is already there.
What it works with, and how
“Runs any old system” would be a blank cheque. Here is the real list, the same as the legacy systems page:
| what | what Perslis does | where you can see it |
|---|---|---|
| Desktop software DOS, Win16, Win32 | Rebuilt and run as it is. The program's own buttons and fields become controls that can be driven. Every session keeps receipts that can be checked. | Software Preservation · white paper |
| Servers and mainframes COBOL, AS/400 | Connected through the ways in they already have — APIs, terminal emulation, data links. Driven, not copied. A COBOL answer is proven by a compiler, or refused. | COBOL preprint |
| Old data DBF, Access, XLS, fixed-width text | Pulled out into SQLite, CSV and JSON, with hash lists and receipts. | Liberate |
| Embedded and firmware | Read and analysed. Running it needs the real hardware or an emulator. | Win95 USB Lab (a driver investigation) |
Why the bridge comes first
A safety floor can only rule on what it can read and what it can do. The bridge gives it both. The old system's state becomes facts, read straight from the program's own controls and data, not guessed. Its operations become a fixed list of actions. Then the floor decides which of those actions may run — the same deal it runs everywhere else (the runtime).
Bridge it, bound it, then let whatever is driving lead. The old system stays. The floor decides what reaches it. Whatever sits on top — a model, a script or a crew — only picks from the moves it is allowed to make right now (any model on top).
What has been shown, and what has not
- Shown: old Windows and DOS desktop software run from its own controls inside isolated guests, with receipts; COBOL code checked by a compiler; old data recovered with hash lists.
- Not shown: military data buses (MIL-STD-1553, ARINC 429, a vehicle's CAN bus), firmware running on target hardware, classified networks, or any fielded system. The bridge has only been used on commercial old software, never on a weapon system.
Where to start
Pick one job on one old workstation. We map it, run it in an isolated copy, and run the floor in shadow mode next to the operator. It writes down what it would have allowed and refused, and why, and touches nothing.