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wickra-shazam

v0.2.0

Published

The data-driven history-fingerprint match core: build a Shazam from a spec, index an asset's history, match the current fingerprint against it. Node bindings powered by Rust.

Readme

Built on Wickra Status CI CodeQL codecov GitHub release crates.io PyPI npm NuGet Maven Central Go module R-universe License: MIT OR Apache-2.0 OpenSSF Scorecard OpenSSF Best Practices Build provenance Docs Verified across 10 languages Live demo


Point at live data → "that's the May-2021 crash setup". Match the current microstructure fingerprint of an asset against its entire history.

▶ Live demos: the backtester compiled to WebAssembly, an equity curve building bar by bar — backtest-live.wickra.org; one StrategySpec side by side in Python, Rust, JS and Go — playground.wickra.org; all 514 indicators of the core over a real Binance feed — live.wickra.org. Zero backend, all of them.

Part of the Wickra ecosystem: the same data-driven core and ten-language binding surface also power wickra-exchange, wickra-backtest, wickra-terminal and 20 more — see the full list.

Wickra Shazam turns an asset's whole history into a rolling index of fixed-dimension microstructure fingerprints — a vector built from the full Wickra feature space (indicators, price, and microstructure: order-book imbalance, funding, open interest, liquidations, footprint) — and matches the current fingerprint against that entire index to name the regime. It is pattern/regime recognition over the full feature space, not price alone.

  • The fingerprint is data — a serde FingerprintSpec (an ordered feature list + window + normalize + metric), not Rust closures, so it crosses the C ABI and WASM unchanged. A fixed dimension N is what makes it deterministic.
  • Deterministic core — indexing and matching are byte-identical across all ten languages and between the parallel (rayon) and sequential (WASM) builds.
  • Three operations, one core — index(history, spec) builds the rolling index, match_current(index, current, k) finds the k most similar historical fingerprints, and a label attaches a human name ("may_2021_crash") to a match.

The core is one library (wickra-shazam-core), usable from Rust, Python, Node.js, WASM, C, C++, C#, Go, Java and R over a JSON-over-C-ABI boundary, plus a reference CLI.

# Index a history and match the current state, human-readable table:
cargo run -p wickra-shazam -- --spec golden/specs/crash_setup.json \
  --history golden/data/history/sym-01.csv --current golden/data/current/sym-01.csv

# Raw MatchReport JSON (the same bytes every binding returns), top 5 matches:
cargo run -p wickra-shazam -- --spec golden/specs/price_euclid.json \
  --history golden/data/history/sym-01.csv --k 5 --format json

Status

0.2.0 — the current release. The core, the CLI, all ten language bindings, the byte-exact golden corpus, property + fuzz tests, benchmarks and one runnable example per language are in place and green across the full CI matrix (10 languages × 3 OS); What comes next is in ROADMAP.md.

Documentation

Quickstart

# Index a history and match the current state, human-readable table:
cargo run -p wickra-shazam -- --spec golden/specs/crash_setup.json \
  --history golden/data/history/sym-01.csv --current golden/data/current/sym-01.csv

# Raw MatchReport JSON (the same bytes every binding returns), top 5 matches:
cargo run -p wickra-shazam -- --spec golden/specs/price_euclid.json \
  --history golden/data/history/sym-01.csv --k 5 --format json

--current defaults to the last window bars of --history. Attach a label to a historical bar with --label <ts>=<name> (repeatable) and it comes back on any match at that timestamp.

FingerprintSpec / features

A spec is a JSON (or TOML) document: an ordered features list, a window, a normalize mode and a metric. The feature order is the vector's axis order and never changes within an index, so the dimension N = features.len() * window is fixed and the fingerprint is fully deterministic.

{
  "features": [
    { "kind": "indicator", "name": "Rsi", "params": [14] },
    { "kind": "indicator", "name": "Sma", "params": [20] },
    { "kind": "indicator", "name": "Atr", "params": [14] },
    { "kind": "price", "field": "close" },
    { "kind": "price", "field": "volume" }
  ],
  "window": 1,
  "normalize": "z_score",
  "metric": "cosine"
}
  • indicator — any PascalCase Wickra indicator resolved from the registry by name + params (Rsi, Sma, Atr, Macd, …), with an optional field to pick a sub-output of a multi-output indicator.
  • price — a raw OHLCV field (open/high/low/close/volume).
  • microstructure — an order-book / flow feature (imbalance, funding, open interest, liquidations, footprint), resolved from the same registry.
  • window — how many consecutive bars are stacked into one fingerprint (1 = the current bar only; > 1 = a short shape).

Similarity & metrics

The metric decides how two fingerprints are compared. Similarity is always mapped to [0, 1] (1 = identical) and rounded deterministically:

  • cosine — cosine of the angle between the flat vectors, mapped from [-1, 1] to [0, 1] via (cos + 1) / 2. Scale-insensitive; good with z_score normalization.
  • euclid — 1 / (1 + d) where d is the L2 distance. Scale-sensitive; pair with min_max or z_score to weight features evenly.
  • dtw — dynamic time warping over the per-bar feature vectors of a window > 1 spec, tolerant of small time shifts between two shapes. With window == 1 it is identical to euclid.

normalize (none · z_score · min_max) is fitted once over the whole index and reused for the current fingerprint, so history and query live on the same axes.

Labels

A label attaches a human-readable name to a historical timestamp; when a match lands on that bar the name rides along in the report:

{ "cmd": "label", "ts": 1700216000, "label": "may_2021_crash" }
// → a later match at ts 1700216000 comes back as
//   { "ts": 1700216000, "similarity": 0.98, "label": "may_2021_crash" }

Use in any language

The same Shazam handle — construct from a JSON spec, drive with command(json) -> json, read version — is reachable from every binding. The commands are set_spec, index, match, label, reset and version; index returns {"indexed":N} and match returns a MatchReport that is byte-identical to the CLI's --format json.

from wickra_shazam import Shazam
s = Shazam('{"features":[{"kind":"price","field":"close"}],'
           '"window":1,"metric":"euclid"}')
s.command('{"cmd":"index","history":[/* candles */]}')
report = s.command('{"cmd":"match","current":[/* candles */],"k":5}')  # JSON MatchReport

The C ABI hub (bindings/c) backs C, C++, C#, Go, Java and R; Rust, Python, Node.js and WASM are native. See each bindings/<lang>/README.md and the runnable examples/.

Project layout

crates/shazam-core     the deterministic core (FingerprintSpec, index, match_current, labels)
crates/shazam-cli      the CLI (bin: wickra-shazam)
crates/shazam-bench    criterion benchmarks
bindings/{python,node,wasm,c,go,csharp,java,r}   the ten-language surface
golden/                CSV histories, current windows, specs, and byte-exact expected reports
fuzz/                  cargo-fuzz targets (spec_parse, build_index, match_index, normalize_metric)
examples/              one runnable "index a history and match the current state" example per language

Building everything from source

cargo build --workspace
cargo test  --workspace --all-features
cargo test  --workspace --no-default-features   # sequential (WASM) index/match path
cargo clippy --workspace --all-targets --all-features -- -D warnings
cargo run -p wickra-shazam -- --spec golden/specs/crash_setup.json \
  --history golden/data/history/sym-01.csv

Each binding builds from its own directory — see the per-binding READMEs under bindings/.

Testing

Run the suites with the commands in Building everything from source.

  • wickra-shazam-core — unit tests per feature axis, normalisation and metric, the index and search path, the parallel-versus-sequential parity, property tests over histories and the command envelope, and the operating-mode check (a label sent before index and one sent after yield the same match report; re-indexing keeps it). The golden fixtures in golden/ are the anchor: the same (spec, history, current) triple must match to the same report bytes here as in every binding.
  • Every binding asserts the same golden bytes and the same operating-mode equivalence. That is the whole cross-language claim, so it is checked the same way in each one rather than approximated per language: Python with pytest (and a plain runner on 3.9), Node with node --test, WASM through the nodejs build, C and C++ through ctest, C# with dotnet test, Go with go test, Java with JUnit, and R with the shipped tests/smoke.R plus the repository's run_tests.R.
  • Examples — every example under examples/ runs in CI and is held to the version and the matches it prints.
  • Fuzz — fuzz/ holds libFuzzer targets over spec parsing, metric normalisation, the index build and the match; CI runs each for a short smoke.

Requirements

  • Rust 1.86+ — the workspace MSRV; the Node binding needs Rust 1.88.
  • Python 3.9+ — the Python binding.
  • Node 22+ — the Node binding.
  • Go 1.23+ — the Go binding.
  • Java 22+ — the Java binding.
  • R 4.1+ — the R package.
  • .NET 8+ — the C# binding.
  • A C11 / C++17 compiler with CMake 3.15+ for the C and C++ examples.

See each bindings/<lang>/README.md for the per-language build and install.

Benchmarks

crates/shazam-bench measures build_index scaling by history length and feature count, and match_index by index size and metric (cosine / euclid / dtw), parallel vs sequential. See BENCHMARKS.md.

Ecosystem

Part of the Wickra family — each one a data-driven core with a CLI and the same ten-language binding surface:

  • wickra — main library (Rust core + Python / Node.js / WASM bindings + a C ABI for C / C++ / C# / Go / Java / R)
  • wickra-playground — a polyglot strategy playground: one StrategySpec live side by side in Python, Rust, JS and Go, entirely in the browser
  • wickra-exchange — unified market-data + execution across ten crypto exchanges
  • wickra-backtest — event-driven backtester over the Wickra core
  • wickra-terminal — the trading terminal: a TUI and a browser renderer over the stack
  • wickra-screener — parallel multi-symbol screening over 514 streaming indicators
  • wickra-xray — market-microstructure explorer: footprint, order-book heatmap, liquidation map, funding/OI divergence
  • wickra-radar — perp-universe alert radar: OI delta, funding flip, book imbalance, liquidation clusters, OI/price divergence
  • wickra-copilot — local market copilot grounded in real order-book, liquidation and funding microstructure
  • wickra-benchmark — reproducible, golden-verified benchmark suite — recompute any (strategy, dataset, report) in ten languages and confirm it byte-for-byte
  • wickra-strategy-ci — Jest for trading strategies: golden-pin the report, catch regressions in CI, property-test against fuzzed data
  • wickra-verify — confirm or refute a claimed backtest report against its strategy and data, in ten languages
  • wickra-proof — Proof-of-Backtest: deterministic (spec, data) → report + blake3 hash, recomputable byte-for-byte in ten languages
  • wickra-zk — prove a backtest zero-knowledge — on-chain-verifiable performance without revealing the data or the strategy
  • wickra-impact — the backtester that knows you would have moved the market: agent-based fills on the real historical L2 order book
  • wickra-darwin — evolutionary strategy search at millions of backtests per second, mutating and crossing JSON specs across the 514-indicator space
  • wickra-gym — a Gymnasium-compatible, microstructure-aware backtest environment with O(1) steps for deterministic RL rollouts
  • wickra-feature-store — OHLCV and microstructure streams into ML-ready feature matrices over 514 O(1) streaming indicators
  • wickra-genome — a vector database of the whole market: every asset a 514-dim live vector, for similarity search, clustering and anomaly detection
  • wickra-timemachine — scrub the whole market like a video — every symbol, full order book, rewound to any moment via deterministic re-fold
  • wickra-synth — deterministic synthetic market microstructure: OHLCV, order book, trades and funding from a single seed
  • wickra-compile — compile a strategy spec into a standalone deployable: a WASM module, a self-contained binary, or a no_std artifact
  • wickra-embed — allocation-free, no_std streaming indicators for bare-metal and HFT, byte-for-byte identical to the core
  • wickra-pico — the O(1) indicator core running bare-metal on a $5 Raspberry Pi Pico — the LED blinks on the EMA cross

Docs at docs.wickra.org; the marketing site and in-browser demo at wickra.org.

Contributing

See CONTRIBUTING.md and CODE_OF_CONDUCT.md. Commits are signed and in English; open a PR against main.

Security

See SECURITY.md and THREAT_MODEL.md. Report vulnerabilities privately — never in a public issue.

License

Licensed under either of

at your option. Use it, fork it, modify it, redistribute it — commercially or not — file issues, send pull requests; all welcome.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Disclaimer

Wickra Shazam is analysis software: it computes similarity between market states. A historical match is a statistical resemblance, not a prediction and not financial advice — the past setup did not have to repeat, and neither does this one. It places no orders. Trading carries risk of loss; review the code and use at your own discretion.