SDK Reference

cd sdk
mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
cmake --build . -j$(nproc)

cd sdk/build
ctest --output-on-failure

# All 10 test suites pass:
# test_ring_buffer ......... Passed
# test_feature_extractor ... Passed
# test_isolation_forest .... Passed
# test_mahalanobis ......... Passed
# test_crypto .............. Passed
# test_liveness ............ Passed
# test_engine .............. Passed
# test_federated ........... Passed
# test_c_api ............... Passed
# test_differentiation ..... Passed

cd wasm
chmod +x build.sh
./build.sh
# Produces dist/truestroke.js and dist/truestroke.wasm

npm install @truestroke/core

import { TrueStroke } from '@truestroke/core';

const ts = await TrueStroke.init({ userId: 'user_123' });

// Attach to any input element (auto-captures keystrokes)
ts.attachTo(document.querySelector('#my-input'));

// Or feed events manually
document.addEventListener('keydown', (e) => ts.feedKeyDown(e.code, e.timeStamp));
document.addEventListener('keyup', (e) => ts.feedKeyUp(e.code, e.timeStamp));

// Listen for anomalies
ts.onAnomaly((event) => {
  console.log(`Imposter detected: confidence=${event.confidence}`);
  showReauthPrompt();
});

// Reactive listeners
ts.onConfidenceChange((c) => updateConfidenceUI(c));
ts.onStatusChange((s) => updateStatusBadge(s));

// Liveness detection
const liveness = ts.checkLiveness();
// { isLive, isReplay, entropy, jitterPower, wpm, dwellCV, score }

// Federated learning
const gradients = ts.exportGradients();
await fetch('/api/v1/gradients', { method: 'POST', body: gradients });

// Profile
ts.saveProfile();
ts.wipeProfile();  // GDPR-compliant erasure

ts.destroy();  // Cleanup

#include <truestroke/truestroke.h>

// Create and initialise engine
ts::Engine engine;
ts::Config cfg;
cfg.lockThreshold = 0.35f;
cfg.enrollFullKeystrokes = 200;
engine.init(cfg);

// Begin enrollment
engine.enroll("user_123");

// Feed keystroke events (from platform hooks)
ts::KeyEvent ev;
ev.keyCode = 65;          // 'A'
ev.pressTime = 1709000000;  // microseconds
ev.releaseTime = 1709050000;
ev.pressure = 0.0f;
engine.feed(ev);

// Query state
float confidence = engine.getConfidence();  // 0.0 to 1.0
ts::Status status = engine.getStatus();     // ENROLLING | MONITORING | LOCKED

// Set anomaly callback
engine.onAnomaly([](const ts::AnomalyEvent& ae) {
    std::cerr << "Anomaly: confidence=" << ae.confidence << "\n";
});

// Liveness check
auto lr = engine.checkLiveness();
// lr.isLive, lr.entropy, lr.jitterPower, lr.wpm, lr.isReplay

// Profile management
engine.saveProfile();       // encrypted binary to disk
engine.wipeProfile();       // GDPR-compliant erasure

// Federated learning (optional)
auto gradients = engine.exportGradients();
engine.importGlobalUpdate(serverResponse.data(), serverResponse.size());

#include <truestroke/c_api.h>

ts_engine_t* engine = ts_engine_create();
ts_engine_init(engine);
ts_engine_enroll(engine, "user_123");

ts_key_event_t ev = {
  .key_code = 65,
  .press_time = t0,
  .release_time = t1,
  .pressure = 0.0f
};
ts_engine_feed(engine, &ev);

float confidence = ts_engine_get_confidence(engine);

// Anomaly callback
void on_anomaly(const ts_anomaly_event_t* event, void* userdata) {
  // Handle anomaly
}
ts_engine_on_anomaly(engine, on_anomaly, NULL);

// Cleanup
ts_engine_destroy(engine);

cd server
mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
cmake --build . -j$(nproc)

# Run the server
./federated_server --port 8080 --min-clients 5 --epsilon 8.0

ts::Config cfg;
cfg.windowSize = 30;       // keystrokes per feature window
cfg.windowStride = 15;     // stride (50% overlap)
cfg.eifTrees = 100;        // forest size
cfg.eifSubsampleSize = 256; // sub-sample per tree
cfg.eifMaxDepth = 10;      // max tree depth
cfg.mahShrinkage = -1.0f;  // <0 = auto Ledoit-Wolf
cfg.mahDecay = 0.01f;      // exponential decay for drift
cfg.lockThreshold = 0.35f; // confidence below this = lock
cfg.hysteresisWindows = 3; // consecutive anomalous windows
cfg.enrollMinKeystrokes = 50;  // minimum keystrokes for early scoring
cfg.enrollFullKeystrokes = 200; // keystrokes for full enrollment
cfg.encryptProfiles = true; // XChaCha20-Poly1305 at rest