Chebyshev scalarization + evolution-as-inference explorable (0.3.1) (#21)

Chebyshev (inference/pareto.rs): ChebyshevScalarization - weighted-max norm
over an ideal point, latent or fixed weight. Reaches non-convex Pareto front
interiors where weighted-sum optima provably collapse to endpoints; pinned
at the theorem level on the concave front f1=x, f2=1-x^2 (fixed-w contrast
+ weight sweep + latent-w conditional tracking). Docs now state the
latent-w marginal tilt exp(-s*m(w)) honestly for both scalarizations.

Explorable (crates/fugue-evo-wasm + docs): ExploreSmcInference steps the
real inference layer one tempering rung per call (GaussianPrior program,
twin-peaks factor likelihood, fugue smc_prior_particles/normalize/resample/
rejuvenate_particles/CrossoverKernel), streaming particles, ESS, resampling
events, crossover swaps, and the running log-evidence; density_grid returns
the exact tempered target for the heat overlay. Engine tests: determinism,
ladder shape, analytic posterior mean + evidence vs grid quadrature,
annealing concentration (distance-to-nearest-mode). Widget (viz/inference.js)
follows the site conventions (wasm gate + notice, lazy init, seeded scrub,
controls/canvas/instruction/readouts, reduced-motion batch); mounted on the
"Evolution as Inference" architecture page; wasm crate gains ppl feature +
direct fugue-ppl dep. Verified live in a browser against the built pkg
(autoplay ladder, Replay, Reset, Step, readouts).


Claude-Session: https://claude.ai/code/session_01HmWLBR9Zq6hPG5o7URDuNJ

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

Author: alexnodeland

CHANGELOG.md

@@ -7,6 +7,39 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.3.1] - 2026-07-28
+
+### Added
+
+- **Chebyshev scalarization for non-convex Pareto fronts**
+  (`inference::pareto::ChebyshevScalarization`): the weighted-max norm
+  `max_i w_i·(f_i − z_i)` over an ideal point `z`, reaching every weakly
+  Pareto-optimal point — including the non-convex front regions where every
+  weighted-sum optimum provably collapses onto the endpoints. Supports a
+  latent weight (like `ParetoScalarization`) or a **fixed** weight
+  (`with_weight`) for uniform front sweeps. Pinned at the theorem level on
+  the concave front `f1 = x, f2 = 1 − x²`: fixed-w weighted-sum mass avoids
+  the interior (< 0.1) while fixed-w Chebyshev concentrates on the interior
+  front point `x* = (√5−1)/2`, and a weight sweep traces the whole front.
+- **Honest marginal-tilt documentation** for the latent-weight Pareto models:
+  the `w`-marginal is tilted by `exp(−s·m(w))` (the scalarized optimum's
+  value), so the *conditional* `x | w` is what tracks the front; uniform
+  coverage comes from fixed-weight sweeps. New regression
+  `test_chebyshev_latent_weight_conditional_tracks_front` pins the
+  conditional property.
+- **"Evolution as inference" explorable** (evo.fugue.run, Architecture →
+  Evolution as Inference): `ExploreSmcInference` in `fugue-evo-wasm` steps
+  the crate's real inference layer one tempering rung at a time — Gaussian
+  prior program, twin-peaks Boltzmann target, fugue's SMC primitives
+  (reweight / ESS-triggered systematic resampling / typed-MH rejuvenation /
+  crossover kernel), exact tempered-density heat recomputed each rung,
+  β-ladder up to annealed-optimizer territory, and live ESS / log-evidence /
+  swap readouts. The wasm crate now enables the `ppl` feature and depends on
+  `fugue-ppl` directly. Engine pinned by determinism, ladder-shape,
+  analytic-posterior-mean, analytic-evidence, and annealing-concentration
+  tests; the page verified live in a browser against the built wasm.
+
+
 ## [0.3.0] - 2026-07-28
 
 **Inference-first.** fugue-evo's identity is now "an implementation of fugue

Cargo.lock

@@ -12,7 +12,7 @@ lto = true
 
 [package]
 name = "fugue-evo"
-version = "0.3.0"
+version = "0.3.1"
 edition = "2021"
 authors = ["Alex Nodeland"]
 description = "An implementation of fugue for running evolutionary algorithms as Bayesian inference: priors and likelihoods as probabilistic programs, tempered SMC in trace space, annealed optimization, Pareto posteriors - plus a standalone classical EC toolkit"

Cargo.toml

@@ -18,7 +18,8 @@ crate-type = ["cdylib", "rlib"]
 
 [dependencies]
 # Classic EC layer without parallel/checkpoint/ppl features
-fugue-evo = { path = "../..", default-features = false, features = ["std", "classic"] }
+fugue-evo = { path = "../..", default-features = false, features = ["std", "classic", "ppl"] }
+fugue-ppl = { path = "../../../fugue", version = "0.2.1" }
 
 # WASM bindings
 wasm-bindgen = "0.2"