Closes the ADR-185 §13.a follow-up (the tractable, data-independent one of
the three §6.7 gaps): the bound EmbeddingExtractor was random-Xavier-init
only, with NO way to load real weights — so it was structurally untrained.
This adds the *capability* to load weights whenever a trained checkpoint
exists. It does NOT itself produce trained/SOTA embeddings and does NOT
close §6.7 (still no trained checkpoint, no labeled data, no eval harness).
Serialization: not greenfield — EmbeddingExtractor already had
flatten_weights()/unflatten_weights() (flat Vec<f32>). wifi-densepose-aether
is a deliberately dependency-free std-only leaf crate (ADR-185 §13), so
rather than add safetensors/serde/bincode (which would undo the zero-dep
property), the on-disk format is raw little-endian f32 with a 12-byte header
(magic "AETHERW1" + u32 param count) — zero new deps.
Native (v2/crates/wifi-densepose-aether/src/embedding.rs):
- EmbeddingExtractor::save_weights(path) / load_weights(path). load_weights
never panics: errors on unreadable file, short/oversized payload, bad
magic, or a param-count mismatch (delegated to unflatten_weights).
- Default (no weights) construction is UNCHANGED — still random init,
clearly labeled untrained. Purely additive.
Python binding (python/src/bindings/aether.rs, .pyi):
- EmbeddingExtractor.load_weights(path) / save_weights(path) / param_count,
GIL-released, ValueError on bad input.
Tests (both Rust and Python, per the task):
- Rust unit (embedding.rs): load_weights_actually_replaces_weights_and_
round_trips proves the loaded weights MOVE the embedding away from the
random-init baseline (not a silent no-op), match the source extractor
(round-trip), and are bit-identical after the file round-trip; plus a
bad-magic/wrong-count rejection test.
- Cross-language golden (aether_weights_parity.rs + test_aether.py): a
shared deterministic weight formula (w[i]=k/65536-0.5, exact in f32+f64)
written to the AETHER format; both native Rust and the Python binding load
it and must produce the byte-identical embedding SHA-256
(tests/golden/aether_loaded_embedding.sha256) — proving the binding's
load path is bit-identical to native, and (vs the random baseline) that
the loaded weights are actually used.
Verified:
cargo test -p wifi-densepose-aether 98 passed, 0 failed
cargo test --features aether --test aether_parity
--test aether_weights_parity 3 passed, 0 failed
maturin develop --features aether + pytest test_aether.py 13/13 pass
default cargo build (no aether feature) clean
Bind the ADR-024 contrastive CSI embedding surface into the wheel behind
a gated [aether] extra / Cargo `aether` feature, per ADR-185 section 3.2.
Surface (bound against the REAL code at HEAD, not the ADR wishlist):
- AetherConfig -> EmbeddingConfig {d_model,d_proj,temperature,normalize}
- CsiAugmenter -> augment_pair(window, seed)
- EmbeddingExtractor -> embed(csi): 128-dim L2-normed, GIL-released
- info_nce_loss, cosine_similarity (module fns)
ADR-185 section 3.2 also names aether_loss/VICReg components,
alignment_metric, uniformity_metric, forward_dual, and vicreg_* config
fields. None exist in embedding.rs at HEAD, so they are intentionally NOT
bound (a Rust-side gap, not a binding gap) rather than fabricated.
Parity (section 4.1, release-blocking): committed fixture
aether_input.json -> native Rust reference (tests/aether_parity.rs, calls
sensing-server EmbeddingExtractor directly) locks
tests/golden/aether_embedding.sha256; pytest (tests/test_aether.py) runs
the same fixture through the binding and asserts the identical SHA-256 of
the LE f32 bytes. Both pass.
Verified: cargo test --features aether --test aether_parity -> 2/2 pass;
maturin develop --features aether + pytest tests/test_aether.py -> 9/9
pass; default cargo build clean with 0 sensing-server refs in the dep
graph (gate keeps the base wheel lean).
HONEST WHEEL-SIZE FINDING (ADR-185 section 9 / Open Q 11.1, unresolved):
wifi-densepose-sensing-server is an Axum/tokio crate whose tokio/axum/
worldgraph/ruvector deps are NON-optional (only mqtt/matter are
features), so default-features=false does NOT drop them. An [aether]
wheel therefore links the full server tree and BREAKS the ADR-117 section
5.4 <=5 MB budget. The fix is the ADR-sanctioned hoist of embedding.rs
(+ its graph_transformer/sona siblings) into a leaf crate so the wheel
links pure compute only -- a change INSIDE wifi-densepose-sensing-server,
owned by another agent this session, so deferred as a required
pre-release follow-up. P1 binds real code and proves parity today; the
hoist is a wheel-size optimization, not a functional blocker.
Note: building required initializing the worldgraph/rufield/ruvector
submodules (absent in the fresh worktree).
ruv