Rust Task App

GEPA prompt optimization with a Rust task app

Quick Start

cd cookbooks/code/polyglot/rust

# Build release binary
cargo build --release

# Start task app on localhost:8001
ENVIRONMENT_API_KEY=secret ./target/release/synth-task-app

Expose it via Cloudflare:

cloudflared tunnel --url http://localhost:8001

Run GEPA optimization (Banking77):

synth train gepa_config.toml --poll

Source

• main.rs
• gepa_config.toml
• walkthrough.md

Sample Result

Job pl_4f69a1b099a14e4b — 100% accuracy on Banking77.

{
  "job_id": "pl_4f69a1b099a14e4b",
  "language": "rust",
  "algorithm": "gepa",
  "best_score": 1.0,
  "total_time_seconds": 42.1
}