Build a Simulation Monitor

A 6-chapter project tutorial. You will build a trading simulation that generates events, detect patterns with fabula's incremental engine, react to matches in real time, score them by surprise, and use engine forking for speculative "what-if" analysis.

Total time	~2 hours
Difficulty	Intermediate
Prerequisites	Getting Started, basic Rust

What you'll build

A command-line program that:

1. Runs a simple trading simulation producing timestamped events (trades, price changes, alerts)
2. Detects three patterns: insider trading (sequence + negation), market manipulation (repeat-range), and flash crash (concurrent group)
3. Reacts to SiftEvent::Completed and SiftEvent::Negated as they occur
4. Uses why_not to explain near-misses
5. Scores matches with SurpriseScorer and StuScorer
6. Forks the engine to evaluate hypothetical "what if this trade happened?" scenarios

Chapters

#	Chapter	What you learn
1	Simulation Loop	Build an event-producing simulation with MemGraph
2	Define Patterns	Write 3 patterns using both builder API and DSL
3	Incremental Matching	Wire the engine into the simulation loop
4	React to Events	Handle SiftEvents, drain matches, use deadlines
5	Score and Rank	Add surprise scoring to rank matches
6	Speculate with MCTS	Fork the engine for what-if analysis

Each chapter builds on the previous one. Complete code at the end of each chapter.

Setup

cargo new fabula-monitor
cd fabula-monitor

Add to Cargo.toml:

[dependencies]
fabula = { path = "../fabula/crates/fabula" }
fabula-memory = { path = "../fabula/crates/fabula-memory" }
fabula-dsl = { path = "../fabula/crates/fabula-dsl" }
fabula-narratives = { path = "../fabula/crates/fabula-narratives" }

Or, if using published crates:

[dependencies]
fabula = "0.1"
fabula-memory = "0.1"
fabula-dsl = "0.1"
fabula-narratives = "0.1"

Start Chapter 1 →