SlimeRESCUE — Binary-First Legacy Recovery Family
Bit-exact conversion from load modules to Java/COBOL/Rust, for customers whose COBOL source code has been lost.
Source lost during vendor migration, vendor bankruptcy, M&A asset fragmentation, retiree-dependency — an industry-wide open secret. Gartner and Forrester touch on it: 15-30% of the world's 80 billion lines of COBOL (= 12-24 billion lines) are estimated to be source-lost. Still running, too risky to touch, blocked from migration — a domain with extremely high willingness to pay.
LLMs (GitHub Copilot / Claude / watsonx) cannot perform binary
semantic inference and are therefore physically incapable of
bit-exact conversion. Accenture / Capgemini / Micro Focus / Rocket /
mLogica all require source — this market is unreachable for them.
Javatel has consolidated its prior investment in machine-code → Slot IR
technology (SlimeASM-rev / SlimeELF-rev / SlimePE-rev) into the new
independent SKU family SlimeRESCUE.
SKU Structure (5 SKUs)
Combinations of machine-code ISA × load-module container format form 5 SKUs. Each SKU has its own front-end (disassembler + container parser), while the Slot IR / S2-S5 / S6 emitter (5 languages) are fully shared. Same structural pattern as the SlimeCOBOL-MF / -GnuCOBOL split.
SlimeRESCUE-VOS3
Input: Hitachi VOS3 / Fujitsu MSP / GS21 / IBM z/OS LOADLIB (PDS) or s390x Linux ELF.
Output: Java / COBOL / Rust / C# / Kotlin / Go (bit-exact)
Target ISA: IBM S/370 / 390 / z-Architecture (PCM-compatible = identical processing across Hitachi/Fujitsu/IBM)
2026-05-20 achievements:
- z/Arch ISA 33 format families = 100% coverage (1,778 opcodes ingested from GNU binutils s390-opc.txt, vector and niche included)
- Both s390x ELF and z/OS PDS (LOADLIB) supported (incl. EBCDIC member name recovery)
- Slot IR mapping complete (67 mnemonic correspondence table, dialect_id=200 (Linux) / 201 (LM))
- Cross-validated against Hercules 3.13 official emulator — 6/6 disasm match + GR final state (GR1=350) exact match
- Python interpreter + Hercules-style trace output for behavioural verification
- HTTP service exposed on 127.0.0.1:8770 (4 endpoints) for external invocation
- Linux
file(1)recognises SlimeRESCUE-generated ELF as "IBM S/390" confirmed
Market: Domestic regional banks, municipalities, electric utilities, and large insurance companies retiring Hitachi VOS3 / Fujitsu MSP. Overseas: Amdahl / IBM-compatible PCM customers. 2026-2030 is the golden window (concentration of z/OS, GS21, AP8000 retirement schedules).
SlimeRESCUE-MSP (Fujitsu MSP detailed support)
Fujitsu MSP runs on the IBM-compatible ISA, so SlimeRESCUE-VOS3 is usable as-is. This SKU adds MSP-specific runtime / NetCOBOL integration. Derivative of VOS3, +2-4 weeks effort.
SlimeRESCUE-GCOS
Bull GCOS 7 / 8 (European mainframe), Honeywell GCOS, with NEC ACOS-4 (= GCOS 7 derivative) as a secondary path. Implementation via bitsavers' Honeywell architecture spec + reverse engineering.
SlimeRESCUE-ACU
ACUCOBOL-GT load modules. Targeting manufacturing / distribution AcuCorp customers.
SlimeRESCUE-MCP
Burroughs MCP (Unisys ClearPath base) load module support. For Unisys mainframe retirees.
※ NEC ACOS-4 as a standalone SKU is intentionally excluded — see Why Javatel for the rationale. Strategic partnership with NEC is the preferred path.
Why this Binary-First market is monopolisable (3 structural advantages)
- Maximised willingness-to-pay: With source, "rewrite ourselves" is an option. Without source, Javatel is the only option.
- Physical impossibility of competition: LLM-based tools (Copilot / Claude / watsonx) cannot perform binary semantic inference — a hard physical limit. Accenture / Capgemini decline binary-start engagements as "unestimable". Micro Focus / Rocket require source.
- Temporal window: IBM z/OS, Fujitsu GS21, Hitachi AP8000, and Unisys ClearPath retirement schedules are concentrated in 2026-2030 — a 4-year golden window.
Technical Stack (SlimeRESCUE-VOS3 example)
| Phase A | z/Arch instruction disassembler (Python 757 lines, 33 format = 100%, 1,778 mnemonics ingested from GNU binutils s390-opc.txt) |
|---|---|
| Phase B | s390x ELF64 BE parser (260 lines, Linux file(1) recognises "IBM S/390") |
| Phase C | Slot IR mapping (406 lines, 67 mnemonic table, Core64+Ext32 compatible with existing SlimeNENC backend) |
| Phase D | z/OS LOADLIB / PDS parser (275 lines, EBCDIC member name recovery + byte-exact member extraction) |
| Phase E | Python z/Arch interpreter (342 lines, 25 instructions + packed BCD decimal, Hercules-style trace) |
| Hercules cross-val | 6/6 disasm + GR state exact match against Hercules 3.13 official emulator |
| Phase F | unified CLI + HTTP service (127.0.0.1:8770, 4 endpoints, ELF/PDS → slot/java/trace) |
| Total implementation | 3,588 lines (src 2,719 + samples 869) + reference data, all 8 tests PASS, regression 0 |
| WASI port | Phase F-2 achieved (2026-05-20) — ~580 lines of C ported to wasm32-wasi: slimerescue.wasm = 84 KB (about 1/6 of the <500 KB estimate). Python ↔ native ↔ WASM produce byte-exact slot streams (audit_hash match confirmed) |
Related products / pricing
SlimeRESCUE is positioned as a mainframe binary-origin premium SKU, listed at 1.5x = $14.95 per LOC over source-origin SlimeCOBOL (reflects binary-recovery effort + no competing tooling). PSDP bundling, volume discount, and SIer partner margin: see Partners. Details disclosed under NDA.
Related: SlimeCOBOL (source-first) · SlimeASM-rev (x86_64 binary, current) · PSDP (in-language parallelisation)
