python mudlib using telnetlib3
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Jared Miller c52e59c5d4
Process V3 save branch on restore to advance PC past branch data
The Quetzal spec stores the PC pointing at the save instruction's
branch data. On restore, this branch must be processed as "save
succeeded" to advance the PC to the actual next instruction. Without
this, the branch bytes were decoded as an opcode, corrupting execution.

Detect the save opcode (0xB5) immediately before the restored PC to
distinguish in-game saves from out-of-band saves (which don't need
branch processing). Also improve error diagnostics: pop_stack now
raises ZStackPopError with frame context, and the instruction trace
dumps on all exceptions.
2026-02-10 13:15:16 -05:00
.claude Re-copy fixed repos/zvm source into src/mudlib/zmachine 2026-02-09 20:44:21 -05:00
content Add mob templates, registry, and spawn/despawn/query 2026-02-09 11:54:29 -05:00
docs Update if-journey docs with Level 2 integration milestone 2026-02-10 11:18:22 -05:00
scripts Add z-machine save file inspection script 2026-02-10 11:51:55 -05:00
src/mudlib Process V3 save branch on restore to advance PC past branch data 2026-02-10 13:15:16 -05:00
tests Fix Quetzal Stks field mapping: return_pc to caller, varnum to frame 2026-02-10 12:39:40 -05:00
worlds/earth Add seed-based terrain world with movement and viewport 2026-02-07 13:27:44 -05:00
.dockerignore Add a docker container solution 2026-02-09 12:34:56 -05:00
.gitignore Re-copy fixed repos/zvm source into src/mudlib/zmachine 2026-02-09 20:44:21 -05:00
compose.yml Add a docker container solution 2026-02-09 12:34:56 -05:00
demo_terrain.py Add seed-based terrain world with movement and viewport 2026-02-07 13:27:44 -05:00
Dockerfile Add a docker container solution 2026-02-09 12:34:56 -05:00
DREAMBOOK.md Add a dreambook 2026-02-07 12:19:49 -05:00
justfile Strip dfrotz prompt even without preceding newline 2026-02-09 17:55:14 -05:00
mud.tin Add reconnect tintin command 2026-02-10 11:26:41 -05:00
pyproject.toml Wire client capabilities into Player & terrain 2026-02-07 22:44:45 -05:00
README.md Add a simple README 2026-02-07 15:42:07 -05:00
uv.lock Wire client capabilities into Player & terrain 2026-02-07 22:44:45 -05:00

mudlib

A telnet MUD engine. No client needed — just telnet and you're in.

Built on telnetlib3, Python 3.12+, managed with uv.

Quickstart

uv sync
just run

Then connect: telnet localhost 6789

Commands

just check   # lint + typecheck + test
just run     # start the server
just debug   # start with debug logging
just render  # generate world map HTML

What's in here

  • src/mudlib/ — the engine (commands, world, combat, rendering, storage)
  • tests/ — pytest tests
  • worlds/ — world definitions (yaml/toml)
  • docs/ — internal knowledge base
  • DREAMBOOK.md — vision and wild ideas

How it works

The world is a toroidal 2D grid of terrain tiles, not discrete rooms. Players see a viewport centered on their position. Terrain types have mechanics — shallow water slows you, mountains block you, forests hide you.

Combat is timing-based with telegraphed moves and cooldown management, not turn-based.

The server runs a tick-based async game loop alongside the telnet server. SQLite handles persistence. Session mode stacks filter what reaches the player depending on context (exploring, fighting, composing, solving puzzles).