iteration 02 · 2026-07-14

DONE — PR #144 OPEN (stacked on #143) card 107substrate: signsEXACT parity 0.0/0.0

#107 etc_effort_to_compress_logret_sign

Branch feat/odb-ext/etc_effort_to_compress_logret_sign → terrylica/mql5 PR #144 (base = the bootstrap branch; loop never merges). All gates green: parity 5/5 · robustness 5/5 · rust:check · check:all-gates exit 0 · pre-push.

In plain terms

Repeatedly merges the most frequent adjacent pair in the up/down/flat bar-direction string and counts how many merge steps it takes to collapse it to a constant. More effort means more disordered, unpredictable direction flow; less effort means repetitive, potentially exploitable sign patterns. Shipped as ETC/(L−1) ∈ [0,1] on the same gap-aware sign ring as the shipped palindromic-defect feature.

H5 results row (ledger detail)

Substrate	Tier/TOL	Parity batch / stream (max-abs-dev, SPLIT)	non-vacuity	pinned witness	C&H
signs (RG8 gap-nulled, never-reset ring)	EXACT (integer/(L−1))	0.0 / 0.0 (11,200/11,200 bit-identical; None-positions exact)	compared == 11,200 == oracle-finite; 4/4 cells; H3 golden 12,000 lines	EURUSD@5+0 → 0.3248730964467005 (RG8 gap window, bit-exact)	A 8/8 · D 10/10 · 0 conceded

H2 fork teeth replicated cross-language at the bootstrap probe's exact machine numbers: TIE-LATEST 37/60 (max 2.513e-02), SIGNUM 10/65 (max 1.010e-02, REAL 5 dbps zero-sign windows only). H4 pinned range [0.2864321608040201, 0.3434343434343434] bit-exact. H1 recompute bit-identical. Oracle replay byte-identical (sha e9356921…); golden sha b677f286….

Decisions + findings (recorded LOUD)

serde_json float-parse hazard: default parsing is NOT correctly rounded (float_roundtrip off) — produced a 1-ULP FALSE parity breach in the test loader; the EXACT tier caught it (72/198 is bit-identical in Python and Rust). Loader now parses raw tokens via std str::parse::<f64>. Carried to iters 03–06.
Two self-caused drift gates fixed in place: clippy doc_lazy_continuation (a docstring line starting with +); check:feature-catalog-fresh (catalog regenerated, 218 columns).
RG12: crypto odb-py #540 twin neither consulted nor executed; binding source = forex probe REGISTRY (agnostic 540/540 EXACT).
Crash-stress: REAL fixture slices only (first-bar prefix, below-floor prefix, pinned gap-bar slices) → None, never panic.

What landed (lockstep, one feature commit)

kernel etc_effort_to_compress_logret_sign.rs + rolling state + mod.rs
BarOrthogonalExtV1 field · BarBuilder read-before-push wiring · writer.rs BarRow (last field)
schema.sql DDL AFTER palindromic_defect_sign_word · feature_metadata.yaml · regenerated docs/feature-catalog.html
oracle oracle_etc_effort_to_compress_logret_sign.py + oracle/golden jsonl + .sha256 sidecars (dual-dir)
parity suite (5 gates) + robustness suite (5 gates) + C&H record

Next: iter 03 (#108 sequitur_grammar_compression_ratio_logret_sign) stacks on this branch.