Lisp Machine knowledge base

Collections

• Guided tour - Linear beginner stories for learning the UI language while moving through CADR and Genera applications, with reviewed runtime views, many short interaction animations, and separate exhaustive atlases.
• Symbolics Genera and Open Genera - The later Symbolics system, its Virtual Lisp Machine, and preserved Open Genera artifacts.
• MIT CADR and LM-3 - The earlier public MIT Lisp Machine lineage represented by CADR-compatible software and emulation.

Start here

• CADR and Genera interface style guide turns source, preserved-font, and reviewed runtime evidence into separate, release-profiled visual, typographic, layout, and interaction guidance for recreating either system without importing a generic retro aesthetic.
• Publishing the museum documentation site records the Genera-profile static build, interaction model, public font boundary, visual validation, and GitHub Pages deployment contract.
• Software areas and programs of the MIT CADR and Symbolics Genera maps the listeners, editors, mail and communication tools, development environments, services, language products, system facilities, and demonstrations, with links to release-bounded exhaustive catalogs for each preserved system.
• Application dossier coverage defines the finite 60-topic documentation boundary, the editor-depth evidence standard, and the exact completed, grouped, and runtime-blocked status for every catalog entry.
• Reimplementation specification coverage tracks the D01-D60 reconstruction contracts, their release profiles, visual evidence obligations, and completion gates.
• What executes on CADR and Genera Lisp machines follows Lisp source through compiled functions to CADR macroinstructions and microinstructions or Ivory instructions and VLM interpretation, and distinguishes executable code from loader commands and saved-world state.
• CADR System 303 macroinstruction and microarchitecture specification defines the 16-bit compiler-visible ISA, 48-bit control-store engine, release deltas, restart rules, and objective conformance tests.
• Ivory I-machine and Open Genera VLM specification defines the 40-bit tagged object model, complete instruction families, calls, traps, memory translation, VLM execution, and Life Support boundary.
• CADR browser and WebAssembly implementation roadmap gives the complete usim-centered path from deterministic headless execution through display, input, crash-consistent private disks, offline museum release, and optional networking or translation.
• CADR-WEB reproducible museum release evidence scaffolding records M14's deterministic static inventory, direct-input provenance, rights, empty-production receipt-admission boundary, and conformance-report nonclaim of runtime-offline behavior or CW4.
• CADR-WEB-303 ABI1.1 deterministic tracing and snapshot specification defines the new portable-core CDRGTRC1/CDRSNAP1 trace and continuation boundary.
• CADR-WEB-303 ABI1.2 headless WebAssembly core specification specifies the bare Wasm module, dedicated worker, streamed immutable-artifact verifier, bounded memory, and native/Wasm conformance boundary.
• CADR-WEB-303 ABI1.3 boot-media controller specification specifies the selected disk path, volatile boot-scratch overlay, canonical controller/media witnesses, and native/Wasm M4 gate.
• CADR-WEB-303 ABI1.4 deterministic machine scheduler specification specifies guest-slot event ordering, the selected I/O-board subset, worker lifecycle controls, CDRSTATE5, and the native/Wasm M5 gate.
• CADR-WEB-303 ABI1.4 headless System 303 Listener boot oracle specification specifies immutable artifact preflight, exact raw Cadet boot input, the source-defined Listener A/B/C oracle, post-observer quiescence, READY3, and three-run native/Wasm M6 conformance.
• CADR-WEB-303 M6-DEVID1 disk-evidence continuation policy records the separately compiled retained-prefix/SHA-256-tail continuation witness and its explicit, still-unmet READY4 runtime gate.
• CADR-WEB-303 ABI1.5 monochrome display and browser renderer specification specifies raw framebuffer and dirty-transfer semantics, integral rendering, the synthetic native/Wasm pixel gate, and the remaining real-System-303 checkpoint obligation.
• CADR-WEB-303 keyboard input reimplementation specification specifies complete CADR key normalization and scan transitions, deterministic chord ordering, lost-keyup recovery, and accessible browser alternatives.
• CADR-WEB-303 pointer and interactive lifecycle reimplementation specification specifies tablet calibration, ordered button transitions, reset, pause and resume, focus-loss recovery, and generation-scoped worker protocol records.
• CADR-WEB-303 private disk-overlay reimplementation specification specifies immutable bases, crash-consistent private overlay commits, atomic import/export, quota behavior, and reload recovery.
• CADR-WEB-303 audio and Votrax reimplementation specification specifies the selected beeper and speech profiles, deterministic samples and events, worklet behavior, and their remaining runtime evidence gates.
• CADR-WEB-303 debugger reimplementation specification specifies exact-boundary stops, breakpoints, paused inspection, provenance, portable bug records, resume, and stale-owner safety.
• CADR-WEB-303 browser hardening and accessibility reimplementation specification specifies the M13 hostile-input, resource, no-network, worker-loss, persistence, audio, and external accessible-control contract without claiming runtime closure.
• CADR-WEB-303 M13 conformance campaign checklist records case-by-case F01--F15b evidence, source identities, and the remaining runtime obligations before C-M13 can close.
• CADR-WEB portable core and host ABI records the portable machine boundary and the deterministic pull-style contract between the CADR core and native or browser hosts.
• Native CADR instruction-boundary oracle describes the frozen pre-refactor witness used to prove exact clock-slot, canonical-state, and ordered-mutation parity during core extraction.
• Genera browser and WebAssembly investigation roadmap gates a local licensed-world implementation through Ivory engine validation, communication and coprocessor closure, paging, Cold Load, a bounded X11 server, persistence, and explicit useful partial releases.
• Lisp Listeners and editable input reimplementation specification defines the System 46, System 303, and Genera 8.5 Listener state, histories, input editing, ZDT/ZTOP embodiments, command dispatch, recovery, visible regions, and conformance tests.
• Program selection, activities, and window management reimplementation specification defines the release-specific registries, reuse/create selection order, System and Select keys, System Menu transactions, Select Key Selector, Split Screen, live layouts, failure behavior, visual references, and conformance tests.
• Screen Editor and Frame-Up layout design reimplementation specification defines four release-selectable live-window and program-layout profiles, complete staged pointer and command binding trees, geometry and pane algorithms, Undo and partial effects, code generation, Zmacs integration, screenshots, and conformance tests.
• How CLIM was used across the software catalogs audits all sixty dossiers, separating true CLIM applications, ports, consumers, and compatibility hooks from Dynamic Windows and the earlier TV/EINE/ZWEI stack.
• MIT CADR/LM-3 TV window-system reimplementation specification defines release-selectable raster, sheet, exposure, stream, input, selection, menu, frame, constraint, typeout, and environment behavior with implementation, compiled-artifact, runtime, and manual evidence plus conformance tests.
• Symbolics Genera Dynamic Windows reimplementation specification specifies typed presentations, input contexts and handlers, commands, output histories, formatted layout, redisplay, frameworks, panes, and reusable clients against the preserved source tree, world, runtime, manuals, and 1989 paper.
• Ragged window borders in Symbolics Genera identifies the zig-zag edges as four-way viewport-continuation indicators, including the less commonly seen left and right forms, their exact selected-source contract, application inventory, and reviewed runtime evidence.
• RPC, embedding, UX, and Macintosh integration traces the public CADR UNIX-interface boundary through Genera's typed RPC/XDR layers, host embedding, UX services, MacIvory and Macintosh integrations, and Keyboard Control, with complete command and API inventories.
• CL-HTTP and the contributed Web systems reconstructs the server, clients, proxy, W3P, W4, Lambda IR, Showable Procedures/Btree substrate, direct controls, bundled examples, security findings, and verified unloaded-world boundary.
• The Genera HACKS demonstration suite gives all 18 registered demonstrations separate implementation and control studies, with lineage, provenance, source-only findings, and an exact runtime blocker instead of inferred screenshots.
• CADR HACKS, display, sound, and novelty programs gives every active HACKS component, omitted canonical demo, and compiled support object a separate source-grounded treatment, with complete controls and a reviewed live QIX capture.
• DOCTOR, the ELIZA-style conversational program documents the engine, executable rule corpus, complete controls, Multics-to-CADR lineage, source defects, and a reviewed synthetic System 303 conversation.
• Spacewar on the MIT Lisp Machine reconstructs the complete game from the public System 46 and maintained System 303 implementations and verifies its live playfield through the isolated CADR harness.
• Directory, difference, and buffer editors compares Dired, BDired, Edit Buffers, List Buffers, Kill Or Save Buffers, and Compare Directories across the preserved systems, including complete command inventories and implementation/runtime discrepancies.
• Directory, difference, and buffer editors reimplementation specification defines System 46, System 303, and Genera 8.5 view models, complete effective input and presentation trees, deferred-operation ordering, partial failures, reviewed Edit Buffers visuals, protocol surfaces, and conformance tests.
• Help, self-documentation, and Document Examiner connects editor and system Help to Genera's documentation browser, with complete controls, search behavior, source-only findings, and a reviewed live frame.
• Help, self-documentation, and Document Examiner reimplementation specification defines the release-selectable state, exhaustive effective input/gesture trees, failures, private-document bytes, visual requirements, and conformance suite.
• Presentation Inspector in Symbolics Genera explains how Genera diagnoses presentation hierarchies, input contexts, handlers, gestures, menus, priorities, and translator failures.
• Zmail on the MIT CADR/LM-3 and Zmail and mail composition in Genera document the two mail environments, complete release-bounded controls, composition modes, transport boundaries, source findings, and safe runtime observations. The Genera declared-build source manifest gives the rights-safe 47-member version/size/hash oracle. Exact companions close the named-command effects, mail-file grammars and failures, and the System 303 and Genera filter, universe, Profile, and option semantics.
• ZMail and mail composition reimplementation specification defines five separately selectable System 46, System 303, and Genera 8.5 reader and composition targets, their complete effective input trees, persistence and partial-failure order, reviewed visible states, and conformance tests.
• Converse, direct messages, and notifications compares QSend, Converse, SHOUT, network notices, central notification delivery, and the Notifications viewer, including complete controls and reviewed live states.
• Converse, direct messages, and Notifications reimplementation specification defines separate System 46 and maintained System 303 public-source profiles, a System 452.1/Zmail 442.0 licensed-source profile, and a bounded Genera 8.5 System 452.22 runtime witness, with complete effective input trees through its normative CADR and Genera companions.
• Screen Editor and Frame-Up distinguishes live window-hierarchy editing from Genera program-frame design, traces the Screen Editor lineage, inventories every control, and includes fresh runtime evidence.
• Emergency Break and the cold-load stream explains the degraded recovery console in System 46, LM-3 System 303, and Genera, including verified System 303 and Genera evaluations and reviewed runtime captures.
• Emergency Break and degraded interaction paths reimplementation specification gives release-selectable cold-console, complete D04-owned input-tree, exact debugger-transition, ownership, recursive-degradation, failure, visual, and conformance contracts.
• Flavors, classes, CLOS, and the Flavor Examiner separates the CADR object facilities from Genera New Flavors and CLOS, inventories their inspection commands, and records implementation findings and live behavior.
• Trace, Stepper, breakpoints, and call analysis compares execution-analysis models and complete control surfaces from System 46 through Genera, including controlled cross-system runtime evidence.
• Metering and performance analysis compares counter snapshots, page tracing, event metering, sampling, reports, and the Genera Metering Interface without conflating their different implementations.
• File systems and file service follows the pathname, access-path, protocol, store, and user-interface layers from System 46 QFILE through LM-3 Local-File/LMFILE and Genera QFILE, NFILE, NFS, and LMFS.
• MIT disk labels, packs, checkout, and file-system repair and Genera FSEdit and File System Maintenance document storage repair from physical labels through file-system salvage, with complete controls and conservative destructive-operation boundaries.
• Tape systems and the Tape Utility Frame distinguishes the absent System 46 subsystem, the later LMI Tape/TFrame stack in maintained System 303, and Genera's separate tape streams, formats, transports, distribution paths, FEP activity, and complete administration command surface.
• CADR site data, login, and Site Editor and Genera Namespace administration and editor document identity, site/host tables, namespace objects, complete editor controls, persistence boundaries, and the verified empty Genera frame.
• Background services and operations dashboards compares CADR process/operator surfaces with the Genera Mailer, Printer Spooler, Domain Server, and File Server programs and their shared logging substrate.
• Lisp runtime, compiler, and development environment compares the reader/evaluator, language context, storage, scheduler, garbage collector, compiler pipelines, development release, and live machine-code output.
• Ivory, FEP, and Open Genera VLM implementation layers separates the Ivory execution architecture, physical and virtual front ends, Life Support, host controls, debuggers, platform systems, and CADR comparison.
• Compiler Tools, grammars, lexers, and the Syntax Editor reconstructs Genera's shared foreign-language compiler IR, parser generators, incremental lexer/parser, syntax-aware Zmacs commands, templates, and exact unloaded-world boundary.
• Conversion Tools and source migration on Symbolics Genera reconstructs the structured source-to-source engine, all 14 Zmacs commands and query controls, built-in conversion sets, mappings, extension API, and exact unloaded-world boundary.
• The NS electronic-design family reconstructs Basic-NS, Schematic-NS, Gate-Array-NS, PCB-NS, and VLSI-NS; inventories every compiled command, menu action, and gesture; and documents the schematic, simulation, board, IC-layout, interchange, and preservation boundaries.
• CLOE development and runtime environment reconstructs CLOE Developer's Genera-to-Intel migration and delivery pipeline, DOS/Windows CLIM port, Listener/debugger, files, all documented bindings, and exact evidence that the product is absent from the preserved media and base world.
• Symbolics C, FORTRAN, and Pascal environments compares the three integrated Genera language products, their compiler/runtime, editor, listener, debugger, build, library, Lisp-interoperation, and complete recovered language-specific command surfaces.
• System construction, patches, worlds, bands, and distribution follows both systems from declarations and builds through patches, CADR load bands, Genera worlds, delivery worlds, distributions, and restoration.
• Source comparison, Compare/Merge, and version control documents SRCCOM on both systems and preserves the exact disabled-system boundary around Genera's media-present Compare/Merge and Version Control facilities.
• Formatting, spelling, and text production utilities follows FORMAT, FQUERY, grinders, dribbling, spelling, Bolio, Sage, fonts, and editor-side document production across System 46, System 303, and Genera 8.5.
• Concordia, structured documentation, and book design documents the NSage record model, structural Zmacs authoring, Page Previewer, book-design inheritance and Browser, all application commands, serialized formats, CADR/LM-3 boundary, and exact runtime load state.
• Mathematical and numeric facilities on CADR and Genera inventories the complete MATH matrix API, rational/complex layers, numeric families, infix grammars, implementation changes, and a preserved runtime anomaly.
• Macsyma 421 on Lisp machines reconstructs the symbolic-mathematics product, all menu panels and expression gestures, plotting, Help, MEDIT, Display Editor, Zmacs integration, MIT/LM-3 lineage, and exact unloaded-world boundary.
• Joshua rule and inference environment reconstructs the optional expert-system product, predicate protocol, unification, RETE rules, truth maintenance, objects, tracing, metering, commands, presentations, Zmacs support, Jericho examples, and public AMORD lineage evidence.
• Statice persistent object and database environment reconstructs the development, run-time, server, Browser, DBFS/B*-tree storage, transactions, recovery, backup, maintenance, and preservation surfaces.
• Dynamic Windows and presentation-based interaction explains Genera's typed object-to-output links, input contexts, translators, command tables, redisplay, program frameworks, generic programs, and CADR antecedents, with reviewed runtime examples.
• CLIM 2 on Symbolics Genera documents the optional portable UI system, Silica, native/CLX/PostScript ports, complete facility map and default Genera gestures, compiled-only source boundary, and exact unloaded-world result.
• CLIM 2 demonstrations and tutorial programs documents every chooser registration, tutorial stage, test family, command, presentation gesture, dependency, format, implementation finding, and exact screenshot blocker in the inspected optional CLIM media.
• Product and programming examples in Genera audits every bounded Core, Joshua/Jericho, Statice, Color, and CL-HTTP example, with complete direct controls for all fourteen example frames, source-only findings, side-effect boundaries, and exact runtime blockers.
• CLX, remote X screens, and X server facilities on Genera separates guest X clients, the historical hardware-only X server, CLX-CLIM, VLM display transport, and the museum's host-side Xvfb harness.
• FED and the Font Editor generations compares the System 46 old-window, XFED, and new-window branches, maintained System 303 FED, and Genera's separate Bitmap Editor-based Font Editor.
• Bitmap, stipple, and raster paint editors documents CADR PAINT/NPAINT and Genera's Bitmap/Stipple Editor family with complete controls, raster/register semantics, file/object workflows, and source-only defects.
• Genera Graphic Editor and structured drawing inventories the object-based drawing model, all active commands and transforms, gestures, formats, presentation semantics, source-only findings, and exact optional-system runtime boundary.
• Color systems, the Genera Color Editor, and CADR color experiments distinguishes indexed and direct color, inventories the complete Color Editor and Palette interactions, and analyzes the CADR color substrate plus COLORHACK, COLXOR, and CAFE without inventing lineage.
• Inks, faces, and character styles in Symbolics Genera explains semantic family/face/size styles, per-device raster-font mapping, Zmacs and hardcopy customization, native colors and stipples, and the distinct CLIM ink model with source and runtime evidence.
• Gray patterns, textures, and stipples in Symbolics Genera renders all twelve TV gray masks, twenty-five active textures, and six inactive candidates as exact #/. periods; it also documents all nine dynamic pattern roles, density, storage, device selection, customization, application use, runtime reachability, and preservation boundaries.
• Images, drawing primitives, and visual-asset substrates maps Genera's BITBLT, Dynamic Windows drawing, image objects and formats, compression, FrameThrower hardware, and complete installed asset census while linking the distinct public CADR recovery boundary.
• Hardcopy, Press, printing, and plot output follows CADR Press, XGP, DPLT, and Versatec output into Genera's format/device registry, Function-Q capture, printer queues, spooler, and PostScript paths, with two reviewed live option-form crops.
• SUPDUP, Telnet, and the Genera Terminal program traces the network-terminal architecture from CADR NVT windows to Genera's protocol/filter/simulator stack and inventories every local command and option.
• Network terminal applications reimplementation specification defines separately selectable System 46, maintained System 303, Genera selected- source/manual, and Genera 8.5 runtime profiles, with complete effective input trees through its normative CADR and Genera companions, exact connection/protocol/failure contracts, and reviewed disconnected visuals.
• Network services and site utilities compares the CADR Chaos service sets and MIT-local utilities with Genera's generic server framework, complete FTP/TFTP/DNS/Finger/TCP surfaces, security defaults, and fresh read-only registry observations.
• Network transports and protocol architecture compares Chaosnet, Ethernet/ARP, EFTP/QFILE transport, Genera's generic service-path graph, IP/TCP, RPC/NFS, routing, and operator diagnostics across System 46, maintained System 303, and Genera 8.5.
• CADR microcode, microassembler, and console debugger documents the UCODE build and artifact pipeline, incremental microassembly, remote hardware/Lisp inspection, and the complete release-bounded CC command interface.
• CADR diagnostics, checkout, and hardware tools covers the machine-test hierarchy, memory and disk checkout, PROM and controller assemblers, continuity/probe automation, and raw Chaos interface diagnostics.
• Publishing runtime screenshots for museum documentation records the capture-specific U.S. fair-use review, publication limits, license boundary, and reassessment process for curated CADR and Genera runtime images.
• From EINE to ZWEI and Zmacs explains the editor lineage, separates reusable ZWEI machinery from the Zmacs application, and links the code- and runtime-grounded feature and keybinding references for both preserved systems.
• Super modifier uses on CADR/LM-3 and Hyper modifier uses on CADR/LM-3 aggregate public-source roles, ignored/normalized paths, and application-local conventions across the selected System 46 and System 303 profiles.
• Super modifier uses in Genera and Hyper modifier uses in Genera provide the corresponding Genera 8.5 application-by-application catalogs, including inherited Dynamic Windows behavior and optional, compiled, and inactive evidence boundaries.
• EINE, ZWEI, and Zmacs editor-family reimplementation specification defines release-selectable semantic models, command loops, complete source-profile input trees and prefixes, files, modes, lifecycle, failure behavior, reviewed visuals, and conformance tests.
• Directory, difference, and buffer editors reimplementation specification defines the Dired, BDired, Edit Buffers, List Buffers, Kill Or Save Buffers, and Compare Directories reconstruction contracts without conflating their releases or UI substrates.
• Operating Genera through the Xvfb computer-use harness explains authenticated, network-isolated operation of a licensed world, exact-window evidence capture, and why an accepted shutdown confirmation currently ends in bounded forced cleanup without saving guest state.
• Operating CADR through the Xvfb computer-use harness explains how isolated private sessions, current-versus-copy-time fingerprints, and execution-time verification turn computer-use observations into museum evidence.
• MIT CADR on-line help and documentation recovery explains the source-integrated ZWEI, Lisp, flavor, keyboard, and application Help mechanisms and links the tracked public System 46 source corpus.
• Visual assets in the MIT CADR and LM-3 software maps native raster pictures, graphical font atlases, paint patterns, technical drawings, and procedural imagery, with explicit preservation and rights boundaries.
• Color inks and raster patterns in the MIT CADR software explains how sixteen indexed solid fills acquire mutable RGB values and how they differ from the monochrome window system's named stipples.
• MUNCH and Munching Squares on the MIT CADR explains how a classic PDP-1 display idea became an interactive Lisp Machine XOR graphics demo.
• LEXIPHAGE, the Lisp Machine word eater explains how its animated jaws erase large raster-font text and distinguishes three preserved implementations.
• Open Genera world loads and the VLOD format explains what a .vlod contains, why it is closer to a cold heap snapshot than an archive, and what can currently be recovered from one.
• Recovering code and assets from a Genera world explains what “decompiled Lisp” can honestly mean and how resident fonts differ from their original source files.
• Extracting resident fonts from a Genera world provides the reproducible local-only VLOD workflow and links the evidence-graded catalog of all 89 fonts in the inspected world.
• Genera on-line help and documentation recovery explains the Document Examiner's 801-file Sage Binary corpus, three reviewed standalone help files, the additional runtime help layers, and the non-redistributing local extraction workflow.
• MIT CADR font sources and recovery explains the public source-first pipeline and catalogs the trackable BDF and PNG derivatives.
• MIT CADR compiled QFASL font recovery documents the separate non-evaluating extraction of 19 public runtime font objects and the evidence distinguishing them from authoring source.
• Compiled objects, QFASL, relocation, and UNFASL inventories the CADR and Genera loader languages, explains what their inspection tools can recover, and separates compiled files from archives and world snapshots.
• MIT CADR font usage audit identifies source-backed roles where the pinned source supports them and leaves evidence-bounded TODOs for every unresolved name.

Editorial principles

The museum favors primary sources and reproducible artifact inspection. Pages should separate verified facts from local observations, interpretation, and unanswered questions. Licensed historical software is described but not redistributed.

See the writing and research guide for the OKF profile, page conventions, and evidence rules.