# Cookbook
Short, focused recipes for the patterns that come up in practice.
Each recipe is self-contained and small enough to copy into your own
project.
## Recipes
- [Parallelize evaluation with rayon](./cookbook/parallel.md) — when
your `evaluate` is non-trivial, the `parallel` feature pays for
itself almost immediately.
- [Tune a model with expensive evaluations](./cookbook/expensive-evaluations.md)
— `BayesianOpt`, `Tpe`, and `Hyperband` for the 50–500-eval
regime.
- [Compare two algorithms on your problem](./cookbook/compare.md) —
multi-seed harness pattern straight from `examples/compare.rs`.
- [Optimize a permutation (TSP-style)](./cookbook/permutation.md) —
`AntColonyTsp` with a distance matrix.
- [Constrain your search with `Repair`](./cookbook/constraints.md) —
bounds, simplex projection, custom repair.
- [Pick one answer off a Pareto front](./cookbook/pick-one.md) — the
a-posteriori weighted-decision pattern from the `jiggly_tuning`
example.
- [Write your own algorithm](./cookbook/custom-optimizer.md) —
implement `Optimizer<P>` from scratch, à la the
`examples/custom_optimizer.rs` walkthrough.