Adds `BinanceRest::fetch_klines` to `wickra-data`: a blocking historical kline downloader (`GET /api/v3/klines`) and the historical counterpart to the F4 live `BinanceFeed`. It is the last native data-layer primitive needed to drop third-party HTTP/JSON download helpers (`jackson`, `jsonlite`, `urllib`, …) from the examples. ## What - **Core** (`wickra-data`): `fetch_klines(symbol, interval, limit, start?, end?)` built on `ureq` with native-tls — sharing the exact same TLS backend (native-tls 0.2 / SChannel) as the existing tokio-tungstenite live feed, so the two pull one TLS stack, not two. Parses Binance's 12-element array rows via the existing serde infrastructure into validated `Candle`s. Blocking by design (a one-shot request needs no async runtime; the FFI boundary is synchronous anyway). Nine mock-HTTP-server tests cover parse / empty / limit / transport / JSON / invariant-violation paths. - **C ABI**: `wickra_binance_fetch_klines(...)` (blocking drain into a caller buffer, `-1` on error) + regenerated cbindgen header and its vendored Go copy. - **Bindings**: native Node `fetchBinanceKlines` / Python `fetch_binance_klines`; generated Go `FetchBinanceKlines` / C# `BinanceFeed.FetchKlines` / Java `BinanceFeed.fetchKlines` / R `fetch_binance_klines`. C / C++ call the C ABI directly. **WASM is excluded** (browsers use the host `fetch`). The four C-ABI bindings are regenerated from the ScriptHelpers generators (not hand-edited); the regen diff is exactly the new wrapper in each. ## Verification All ten toolchains green locally: Rust (`cargo test`/`clippy`/`fmt`), Node, Python, Go, C#, Java, R (`R CMD INSTALL` + smoke), WASM (`cargo check`, confirmed `ureq` is not pulled). Each binding has an error-path smoke test; the parse/HTTP success path is covered by the Rust mock-server tests. No release in this PR — ships with the data-layer + numpy bundle later.
Wickra — C / C++
Streaming-first technical indicators for C and C++. A prebuilt shared/static
library plus a generated wickra.h — no system dependencies.
Wickra is a multi-language technical-analysis library with a Rust core and bindings for Python, Node.js and WASM, plus a C ABI for C, C++, C#, Go, Java, R and any other C-capable language. Every indicator is an O(1) streaming state machine, so live trading bots and historical backtests share the exact same implementation. This package is the C ABI hub: it compiles the core to a C-compatible shared/static library plus a generated header, so any C-capable language (C, C++, C#, Go, Java, R) links against one artifact instead of re-wrapping every indicator natively.
Install
Grab the prebuilt header + library for your platform from the
GitHub releases — each archive
has wickra.h, the optional wickra.hpp C++ wrapper, and the shared/static
library — or build from source:
cargo build -p wickra-c --release
# -> target/release/libwickra.{so,dylib} or wickra.dll (+ import lib) + a staticlib
Then compile against the header and link the library
(cc app.c -I include -L lib -lwickra -lm -o app).
Quick start
#include "wickra.h"
struct Rsi *rsi = wickra_rsi_new(14); /* NULL on invalid params */
for (size_t i = 0; i < n; ++i) {
double v = wickra_rsi_update(rsi, prices[i]); /* NaN during warmup */
if (v == v && v > 70.0) /* v == v is the NaN check */
printf("overbought\n");
}
wickra_rsi_free(rsi); /* exactly once per _new */
Every indicator is an opaque handle with the same five functions —
_new / _update / _batch / _reset / _free. update is O(1); there is no
RAII across the C boundary, so each _new needs exactly one _free, and every
function is NULL-safe (a NULL handle yields NaN or a no-op, never a crash).
Multi-output indicators (MACD, Bollinger, ADX, …) take a pointer to a #[repr(C)]
struct and return a bool. The optional wickra.hpp wraps any handle in a
move-only wickra::Handle for exception-safe C++ lifetimes.
Benchmark
benchmarks/throughput.c reports streaming and batch updates-per-second for
SMA, ATR and MACD. As the thinnest binding it is the floor of the
per-binding FFI overhead — not a cross-library ratio (the same Rust core runs
under every binding); see the repository
BENCHMARKS.md §3.
cargo build -p wickra-c --release
cmake -S benchmarks -B build && cmake --build build
./build/throughput
Documentation
The full indicator catalogue, guides, quickstarts, and API reference live in the main repository and documentation site:
- Repository & full indicator list: https://github.com/wickra-lib/wickra
- Docs (C quickstart, cookbook, TA-Lib migration): https://docs.wickra.org/Quickstart-C
- Runnable examples:
examples/c/
Wickra ships native bindings for Python, Node.js, WASM and Rust, plus this C ABI hub that any C-capable language (C, C++, C#, Go, Java, R) links against — all exposing the same indicators from the shared Rust core.
Security
Found a security issue? Please don't open a public issue. Report it privately
via the affected repository's Security tab ("Report a vulnerability") or email
support@wickra.org with a subject line starting [wickra security]. Full
policy: https://github.com/wickra-lib/wickra/blob/main/SECURITY.md.
Disclaimer
Wickra is an indicator toolkit, not a trading system. The values it computes are deterministic transforms of the input data — they are not financial advice and do not predict the market. Any use in a live trading context is at your own risk. The library is provided as is, without warranty of any kind.
License
Licensed under either of Apache-2.0 or MIT at your option.