Amble

Data‑first interactive fiction engine and authoring DSL in Rust.

How It Started

I wanted to learn Rust and thought an 80s‑style parser adventure (think Zork) would be the perfect project to dig in to many different aspects of the language. A small game prototype quickly snowballed into a data‑driven engine, a friendly DSL, and tooling to build real adventures -- along with a fairly extensive demo game that utilizes each of the available engine features in some way.

What It Is Now

Amble is a data‑centric engine that loads worlds from compiled WorldDef data (world.ron or worlds/*.ron), plus a DSL and compiler that make worldbuilding fast and readable. The repo includes developer tools and a fully playable demo you can run immediately.

The WorldDef *.ron file is not edited directly to create the game. That's what the Amble DSL is for...

DSL Spotlight

The Amble DSL is designed to read like plain English while staying precise and composable.

• Start with amble_script/docs/dsl_creator_handbook.md for the language tour.
• For rich editing, see the Zed Amble extension - powered by tree-sitter-amble.

In Play

The compiled data runs as a classic parser adventure in the terminal, with theming, status UI, and a REPL for command-driven play.

Quickstart

Play Now (prebuilt ZIP)

• Download the appropriate ZIP from Releases.
• Extract and run amble_engine (use amble_engine.exe on Windows).
• Type help in the game REPL for commands. Saves go to saved_games/<world>/.

Build & Tinker (Rust toolchain)

1. Install the latest stable Rust toolchain.
2. Clone this repository and cd into it.
3. Run the engine with the bundled content: cargo run -p amble_engine
4. Use help in the REPL; saves land in saved_games/<world>/.

Author New Content

1. Explore the DSL guides in amble_script/docs/—start with dsl_creator_handbook.md.
2. Compile the sample DSL to world.ron: cargo run -p amble_script -- compile-dir amble_script/data/Amble --out-dir amble_engine/data (Use --out-world amble_engine/data/worlds/<slug>.ron to add multiple worlds.)
3. Launch the engine to test your changes: cargo run -p amble_engine
4. Iterate with amble_script lint … to catch missing references early.

Crates in this Repository

• amble_engine - loads compiled world data from world.ron or worlds/*.ron, plus static support files such as themes/help, or a saved state, then runs the game
• amble_script - an intuitive, English-like language (DSL) for defining the game world, which compiles into WorldDef (RON) used by amble_engine
• amble_data - world data model, shared between amble_engine and amble_script.
• xtask - automation helpers for builds, packaging, and the content pipeline

Optional (but nice!) External Repositories for Developers

• tree-sitter-amble - a tree-sitter parser / syntax highlighter for the amble_script DSL
• zed-amble-ext - a full-featured extension for the Zed editor with syntax highlighting and a language server (supports outlining, references / go-to-definition, symbol renaming, formatting, diagnostics, autocomplete -- development still ongoing.)

Engine Features

• Data-first design so stories and puzzles live entirely in .amble -> world.ron (or worlds/*.ron) data, not code
• Game Chooser (added v0.66.0) - if multiple valid AmbleWorld (*.ron) files are present, the engine starts with a chooser to pick a new or saved game from the available options.
• Rooms with conditional description overlays that can adapt to world state and connections (exits) that can be conditional, hidden, locked, or remapped entirely during play
• Items support a variety of capabilities (like "ignite" or "smash" or "turn on") and interactions, and can be consumable; items can also be containers and nested to an arbitrary depth.
• NPCs supported with dialogue, trade options (via triggers), moods/states, and movement on either predetermined routes or randomly through a defined area
• Goals / Achievement system to help guide players to important objectives and mark progress
• Configurable point scoring system / report card.
• Customizable status effects
• In-game help system for players (built-in help for commands with customizable general help text.)
• WorldDef validation plus a placement pass that seeds initial room/NPC/item locations
• Thorough logging of game and engine events enabled throughout
• REPL-style parser with natural language verbs, synonyms, and tab-to-complete.
• Powerful trigger/scheduler system for conditional, delayed, cascading or repeating events
• Flexible flag model: either simple boolean flags or "sequence" flags that can track progression through multiple steps or severity
• Themeable terminal UI with multiple palettes and optional styling
• Simple terminal markup allows additional styling for emphasis on top of the active theme (but also theme-aware)
• Save system (RON full game state snapshots) for restoring worlds mid-adventure
• Comprehensive test suite and CLI for fast iteration

Engine Development / Contributions

• Any ideas / comments or contributions welcome!
• I check the repo Issues and Discussions regularly.