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Feature Roadmap

This page tracks where 3270Web stands today against the s3270 binary's exposed action surface and against competing 3270 emulators (PCOMM, Rumba+, Reflection, BlueZone, HostExplorer, Vista TN3270, Inventu Viewer+, z/Scope, Mocha, Flynet, Virtel, Glink, ZOC, x3270). It is a menu, not a schedule — items in Future candidates are deliberately unprioritized.

Recently shipped

  • Host Compatibility Profiler — POST /profile and POST /api/v1/sessions/:id/profile produce a shared CompatibilityProfile JSON document. Same schema as 3270Connect -profile, so the same JSON drops into either tool's comparison workflow. See Host Compatibility Profiler.
  • Chaos Mind-Map Compare — POST /chaos/mindmap/compare diffs two exported mind maps and surfaces field and transition divergence between hosts. JSON by default, HTML report on Accept: text/html. See Chaos Mind-Map Compare.
  • IBM 3270 terminal fonts — three bundled web fonts (Regular, Semi-Condensed, Condensed) selectable from the Settings modal. See Terminal Fonts.
  • AI Chat model selector — dropdown in the side-panel header to switch between Copilot models (default Claude Opus 4); choice persists across page reloads.
  • Chaos learned-value reuse bias controls — CHAOS_LEARNED_INPUT_REUSE_BIAS, CHAOS_LEARNED_KEY_REUSE_BIAS, and CHAOS_EXPORT_SUCCESS_BALANCE let operators tune how aggressively the engine reuses values, keys, and successful transitions in exports.
  • Accessibility & UX hardening — destructive-action confirmation modal for saved-host deletion, visual destructive tagging on Disconnect, hostname input marked required with AT-announced errors, collapsible toolbar sections, theme-aware toast notifications.

Where 3270Web stands today

Bucket Current state
Core terminal TN3270 with TLS, themed rendering (IBM 3270 fonts, 7 themes), virtual keypad, browser copy/paste, settings modal with diagnostics, sample 3270 servers for testing. New in this release: print screen via s3270 PrintText().
s3270 exposure All AID keys, navigation, Connect, readbuffer ascii, Wait(Unlock,...), movecursor, eraseeof, newline. New in this release: field writes via s3270 String() (was per-character key(0x..)); PrintText() for print screen.
Modernization / web-native Cookie-session web UI, embedded s3270, Windows desktop wrapper, Docker image, MkDocs site. New in this release: public REST/JSON API at /api/v1/*.
Automation / AI Workflow recording/playback (3270Connect-compatible JSON), chaos exploration with hints, GitHub Copilot side panel driving the host via tool calls.

Table-stakes gaps vs. competitors

Items most enterprise emulators ship that 3270Web does not yet have.

  • IND$FILE file transfer (s3270 Transfer()) — text and binary, ASCII/EBCDIC
  • Print screen (s3270 PrintText()) — shipped: toolbar button → opens printable HTML in a new tab
  • Multiple concurrent sessions / tabs in one browser — today, one session per cookie
  • Rectangular block copy/paste — today, browser-native selection only
  • Scrollback / screen history navigation
  • Find/search within current screen
  • Hotspots (clickable PF labels and URLs detected on screen)
  • Auto-reconnect on host drop
  • Named saved sessions / connection profiles
  • Customizable keyboard mapping in the UI (multiple profiles)

s3270 features not yet surfaced

s3270 already supports these — wiring them up is mostly a wrapper job.

  • String() for batched field writes — shipped: replaces per-character key(0x..) loop
  • Transfer() — IND$FILE; see Table-stakes gaps above
  • Snap() — point-in-time screen snapshots; enables diffing and regression tests
  • Query(host|model|cursor|...) — richer status surface for the UI and API
  • PrintText() — shipped
  • Toggle() / Set() — runtime resource changes (e.g. monocase, blink)
  • Source() / Macro() / Script() — native s3270 scripting
  • ScreenTrace — event-driven screen-change capture for observability
  • Explicit Disconnect — today the subprocess is killed; a graceful Disconnect is friendlier to upstream proxies

Modernization / web-native

  • Public REST/JSON screen API — shipped at /api/v1/* (see REST API)
  • OAuth / SAML / OIDC SSO — Inventu Viewer+ ships this; needed for BYOD and Azure AD orgs
  • Audit logging for compliance (who did what, when, against which host)
  • WCAG 2.1 AA + screen-reader support — near-zero in the competition, large untapped differentiator
  • Embed-in-iframe / SPA integration story documented end-to-end
  • Mobile / touch UI — today the UI is desktop-first; touch-friendly keypad and hotspots would unlock tablet use

Automation / AI

Build on the existing Copilot + chaos + workflow plumbing.

  • HLLAPI-shape scripting endpoint for external bots — partially solved by the new REST API; a thinner "HLLAPI compatibility" wrapper could ease migration from PCOMM/Rumba
  • Macro recorder polish — the workflow recorder exists; surface it as "macros" with named, parameterized re-runs
  • Natural-language → keystrokes — extend the Copilot tool surface with a "describe the screen action you want" action
  • One-click "Explain this screen" — Copilot already has get_screen; a button can chain it with a fixed prompt

Differentiator opportunities

If 3270Web wants to lead rather than match, the standouts are:

  1. Accessibility — almost nobody in this category has a documented WCAG/screen-reader story. A modern web emulator with ARIA labels, keyboard-only operation, and high-contrast themes wins regulated-industry RFPs by default.
  2. AI-assisted use — the Copilot side panel is already unusual; doubling down on screen-aware Copilot actions, natural-language transactions, and AI explanations puts daylight between 3270Web and every desktop competitor.
  3. Public REST API + workflow JSON — paired, these make 3270Web the easy choice for RPA and CI integration. Competitors either gate this behind expensive enterprise tiers or don't ship it at all.

In-flight (this release)

Terminal / API

  • E1: s3270 String() for field writes — performance and observability win; replaces the per-character key(0x..) loop noted as a TODO since the Java port.
  • E2: Print screen — table-stakes parity with PCOMM, Rumba+, BlueZone.
  • E3: Public REST API — modernization differentiator; reuses the existing Copilot tool plumbing.

Chaos exploration

  • Bug fix: chaos_save_screen_hint and chaos_start now bind both snake_case (the public MCP form) and camelCase (the legacy UI form). Tool descriptors are unchanged.
  • Saturation detection: a run stops early with terminationReason: "saturated" once saturation_steps consecutive attempts produce no new screen, transition tuple, or value that caused a transition. coverageStats is surfaced in chaos_status.
  • Smarter value generation: built-in corpus expanded with real-looking transaction codes (LOGON, IPL, IKJEFT01, TSO, CICS, ISPF, …) and realistic names; per-field length-probe values (empty / short / half / exact / overflow) cycle through untried length classes.
  • Structural dedup as default: mind-map area keys now derive from the layout signature, so screens that differ only by echoed values (e.g. "first name is 1" vs "first name is 3") collapse into one area. Use dedup_mode: "exact" for the old raw-hash behaviour.
  • Auto-block exit keys: chaos scans the bottom-row PF legend for Exit/Quit/Cancel/Logoff labels and blocks those keys for the rest of the run. Navigation labels (Help/Menu/Next/Prev/Forward/Back) are auto-known.
  • chaos_report tool returns a Markdown report (ASCII screen graph, per-screen field/key stats, suggested next experiments). Backs the existing in-browser report modal.
  • chaos_status now supports ?verbose=true; default response is a slim mind-map summary so polling is cheap.
  • Mind-map carry-across via GET /chaos/mindmap/export and POST /chaos/mindmap/import.
  • Optional JSONL transition log per run via transition_log_path for offline analysis.