Wickra Backtest

June 28, 2026 · View on GitHub

Wickra — streaming-first technical indicators

Built on Wickra CI codecov License: MIT OR Apache-2.0

Wickra Backtest — Java

Java binding for the wickra-backtest engine. It calls the stable C ABI through the Java Foreign Function and Memory API (FFM, stable since Java 22 — no preview flags), so the results are byte-identical to the Rust, Python, Node.js, WASM and C# bindings: one engine kernel behind every language.

Requirements

  • Java 22+ (tested on 25)
  • The native library wickra_backtest (built from the C-ABI crate)

Build the native library

cargo build -p wickra-backtest-c          # debug   -> target/debug
cargo build -p wickra-backtest-c --release # release -> target/release

This produces wickra_backtest.dll (Windows), libwickra_backtest.so (Linux) or libwickra_backtest.dylib (macOS).

Run the tests

mvn test passes the target directory on java.library.path (see pom.xml):

cd bindings/java
mvn test

Usage

Put the native library on java.library.path (-Djava.library.path=/path/to/target/debug) and call:

import org.wickra.backtest.Backtester;

double[] open  = { 100.0, 102.0, 104.0, 98.0 };
double[] high  = { 101.0, 103.0, 104.0, 98.0 };
double[] low   = { 100.0, 102.0,  99.0, 97.0 };
double[] close = { 101.0, 103.0,  99.0, 97.0 };

String spec =
    "{\"symbol\":\"x\",\"timeframe\":\"1h\",\"indicators\":{},"
  + "\"entry\":{\"gt\":[{\"price\":\"close\"},100]},"
  + "\"exit\":{\"lt\":[{\"price\":\"close\"},100]},"
  + "\"sizing\":{\"type\":\"fixed_qty\",\"qty\":1}}";

String reportJson = Backtester.run(open, high, low, close, spec); // capital defaults to 10,000
System.out.println(reportJson);

run overloads:

  • run(open, high, low, close, spec) — zero volume, 0..n timestamps, capital 10,000
  • run(open, high, low, close, spec, capital)
  • run(open, high, low, close, volume, time, spec, capital) — full control

The returned JSON is the same BacktestReport as every other binding (metrics, trades, equity, fees_paid, initial_capital). An invalid spec or mismatched inputs throw IllegalStateException / IllegalArgumentException; no panic ever crosses the FFI boundary.

Documentation

The same StrategySpec runs identically across Rust, Python, Node.js, WASM, C, C++, C#, Go, Java and R — one engine kernel, byte-identical reports.

Security

Found a security issue? Please don't open a public issue. Report it privately via the repository's Security tab ("Report a vulnerability") or email support@wickra.org. Full policy: https://github.com/wickra-lib/wickra-backtest/blob/main/SECURITY.md.

Disclaimer

Not a trading system. Backtest results are deterministic transforms of the input data — they are not financial advice and are not indicative of future performance. Any use in a live trading context is at your own risk. Provided as is, without warranty of any kind.

License

Licensed under either of MIT or Apache-2.0 at your option.