SlimeGENBA-LUI — Legacy UI (LUI) for mainframe terminals
The problem competitors keep failing to solve. Operator floors run on 30-year-old 3270 / Hitachi F-series / Fujitsu MSP / NEC ACOS terminals. Veteran operators do blind-type at ~1,500 transactions per day using only TAB / ENTER / PF keys. Forced web migration (Micro Focus / Blu Age / AWS MMA) drops productivity to ~400-600 / day and triggers operator rejection — modernization projects stall or fail outright.
SlimeGENBA-LUI's answer. A 2-layer architecture that preserves the Legacy UI (LUI) instead of forcing replacement:
- Layer 1 · LUI (Legacy UI / 現場 Mode) — terminal-authentic look + keyboard semantics. All four vendors (IBM 3270 · Hitachi F-series · Fujitsu MSP · NEC ACOS-4) supported. Operator skill 100 % preserved.
- Layer 2 · MUI (Modern UI) — optional modern overlay sharing the exact same keyboard semantics. Useful for newer staff and progressive modernization, never forced.
▶ Touch the 2-layer UI directly
14 hands-on evaluation demos: 11 real CICS BMS maps auto-emitted, 3 Japanese-vendor scaffolds (Hitachi / Fujitsu / NEC), plus a React-modern proof rendering the same map with React 18 + Tailwind. Keyboard-only, no mouse required, runs offline.
Open the demo subsite → (early-stage evaluation, IBM BMS production-ready; 3 vendor parsers are scaffolds pending NDA samples)
Keyboard map
| F12 | Toggle Layer 1 (LUI) ↔ Layer 2 (MUI) |
| F11 | Cycle vendor: IBM 3270 → Hitachi F-series → Fujitsu MSP → NEC ACOS-4 (Layer 1 colour tint changes) |
| F10 | Cycle map (for multi-map mapsets) |
| F1 | Help overlay |
| F2 – F12 | PF2 – PF12 (DFHAID equivalents) |
| Esc | PF3 = Exit (mainframe convention) |
| TAB / Shift+TAB | Next / Prev unprotected field |
| Enter | Submit (EXEC CICS RECEIVE MAP equivalent) |
| Ctrl+R | Reset / clear all unprotected fields |
| Home / End | First / last field |
| Mouse | Not required (intentional — preserves operator skill) |
What SlimeGENBA-LUI delivers
- 11 / 11 real-corpus BMS maps emit successfully on the internal test corpus (IBM CICS Banking Sample · cics-genapp · CLBS adversarial bench)
- 624 fields · 102 UNPROT inputs · 6 colours · OCCURS expansion · PICIN/PICOUT editing all rendered
- Layer 1 ↔ Layer 2 toggle preserves keyboard semantics — same keystroke sequence works in both
- Layer 2 wraps all four vendors agnostically (IBM ships now; Hitachi XMAP / Fujitsu MELT / NEC OLF parsers land as sibling crates as NDA samples arrive)
- Single self-contained
.htmlper map — no build, no framework, no npm. Runs on any browser, no server required.
Technical details
- Emitter: Rust crate
bms_to_ui(~660 lines, no-external-lib, std-only) - Output: HTML + vanilla JS, ~14-37 KB per emitted page
- Picture-clause coverage:
9/Z/./,/B///$static & floating /+/-static & floating /X(N)/A(N)/OCCURS=N - Validation: 19 / 19 Rust unit tests verifying picture editing semantics (covers static & floating
$, comma suppression, zero-suppress, sign editing, OCCURS stacking)
Test corpus sources. IBM CICS Banking Sample Application (CBSA) and cics-genapp are Apache 2.0 licensed. CLBS is MIT-style licensed. All BMS files are referenced for technical analysis only.