diff --git a/cmd/mavwaked/wakefeatures.go b/cmd/mavwaked/wakefeatures.go
new file mode 100644
index 0000000..1ba69ae
--- /dev/null
+++ b/cmd/mavwaked/wakefeatures.go
@@ -0,0 +1,187 @@
+package main
+
+// The three models behind the wake word (V-487 stage two).
+//
+// openWakeWord's pipeline, run in a row:
+//
+//	audio      -> melspectrogram.onnx -> 32-bin mel frames, one per 10ms
+//	76 frames  -> embedding_model.onnx -> one 96-dim embedding per 80ms
+//	16 embeds  -> maven_wakeword.onnx  -> one score
+//
+// The first two are frozen and pretrained. Only the last was trained here,
+// which is why it is 100KB and the other two are megabytes. The shapes are
+// not guesses: 2.0s of 16kHz audio measures 197 mel frames, and 76-frame
+// windows at stride 8 give exactly the 16 embeddings the head was fitted on.
+//
+// This file knows ONNX and nothing about the 80ms cadence. wakeword.go knows
+// the cadence and nothing about tensors.
+
+import (
+	"fmt"
+
+	ort "github.com/yalue/onnxruntime_go"
+)
+
+const (
+	// melHop — samples per mel frame. 10ms at 16kHz.
+	melHop = 160
+	// melBins — mel bins per frame, fixed by melspectrogram.onnx.
+	melBins = 32
+	// embedFrames — mel frames one embedding is computed over, 760ms.
+	embedFrames = 76
+	// embedStride — mel frames between embeddings, 80ms.
+	embedStride = 8
+	// embedDim — the embedding width.
+	embedDim = 96
+	// headWindow — embeddings the head scores at once, 1.28s of audio.
+	headWindow = 16
+
+	// melContext — samples of history prepended to each incremental mel
+	// call, chosen so the eight frames this call yields continue exactly
+	// where the previous call's eight stopped.
+	//
+	// melspectrogram.onnx returns N/160-3 frames for N samples, and frame i
+	// covers [i*160, i*160+400). With 480 samples of history the buffer is
+	// 1760 samples, which is 8 frames, and the oldest of them starts one hop
+	// after the newest of the previous call. Less history leaves a gap: the
+	// first frames of a bare chunk would be computed against silence.
+	melContext = 480
+
+	// chunkSamples — audio per embedding step, 80ms.
+	chunkSamples = embedStride * melHop
+)
+
+// wakeModels holds the three ONNX sessions. It runs on CPU threads beside
+// silero and never touches the GPU. That is a rule, not a result: a wake word
+// that waits on card admission is not a wake word.
+type wakeModels struct {
+	mel  *ort.DynamicAdvancedSession
+	emb  *ort.DynamicAdvancedSession
+	head *ort.DynamicAdvancedSession
+}
+
+// newWakeModels loads all three. melPath and embedPath are openWakeWord's
+// frozen feature models; headPath is the keyword head trained for "Мэйвен".
+func newWakeModels(melPath, embedPath, headPath, libPath string) (*wakeModels, error) {
+	if !ort.IsInitialized() {
+		if libPath != "" {
+			ort.SetSharedLibraryPath(libPath)
+		}
+		if err := ort.InitializeEnvironment(); err != nil {
+			return nil, fmt.Errorf("wake word: onnx runtime: %w", err)
+		}
+	}
+	open := func(p string, in, out []string) (*ort.DynamicAdvancedSession, error) {
+		s, err := ort.NewDynamicAdvancedSession(p, in, out, nil)
+		if err != nil {
+			return nil, fmt.Errorf("wake word: load %s: %w", p, err)
+		}
+		return s, nil
+	}
+	m := &wakeModels{}
+	var err error
+	if m.mel, err = open(melPath, []string{"input"}, []string{"output"}); err != nil {
+		return nil, err
+	}
+	if m.emb, err = open(embedPath, []string{"input_1"}, []string{"conv2d_19"}); err != nil {
+		m.Close()
+		return nil, err
+	}
+	if m.head, err = open(headPath, []string{"embeddings"}, []string{"score"}); err != nil {
+		m.Close()
+		return nil, err
+	}
+	return m, nil
+}
+
+// Close releases the three sessions.
+func (m *wakeModels) Close() {
+	if m == nil {
+		return
+	}
+	for _, s := range []*ort.DynamicAdvancedSession{m.mel, m.emb, m.head} {
+		if s != nil {
+			s.Destroy()
+		}
+	}
+	m.mel, m.emb, m.head = nil, nil, nil
+}
+
+// melFrames runs one buffer of samples and returns the mel frames it yielded.
+func (m *wakeModels) melFrames(buf []float32) ([][melBins]float32, error) {
+	in, err := ort.NewTensor(ort.NewShape(1, int64(len(buf))), buf)
+	if err != nil {
+		return nil, err
+	}
+	defer in.Destroy()
+
+	n := int64(len(buf)/melHop - 3)
+	if n < 1 {
+		return nil, fmt.Errorf("wake word: %d samples yield no mel frames", len(buf))
+	}
+	out, err := ort.NewEmptyTensor[float32](ort.NewShape(1, 1, n, melBins))
+	if err != nil {
+		return nil, err
+	}
+	defer out.Destroy()
+
+	if err := m.mel.Run([]ort.Value{in}, []ort.Value{out}); err != nil {
+		return nil, err
+	}
+	data := out.GetData()
+	frames := make([][melBins]float32, n)
+	for i := range frames {
+		for j := 0; j < melBins; j++ {
+			// The scaling openWakeWord applies between the two feature
+			// models, and the head was fitted on its output.
+			frames[i][j] = data[i*melBins+j]/10.0 + 2.0
+		}
+	}
+	return frames, nil
+}
+
+// embedding runs embedFrames mel frames through the frozen embedder.
+func (m *wakeModels) embedding(mels [][melBins]float32) ([embedDim]float32, error) {
+	var e [embedDim]float32
+	flat := make([]float32, 0, embedFrames*melBins)
+	for _, f := range mels {
+		flat = append(flat, f[:]...)
+	}
+	in, err := ort.NewTensor(ort.NewShape(1, embedFrames, melBins, 1), flat)
+	if err != nil {
+		return e, err
+	}
+	defer in.Destroy()
+	out, err := ort.NewEmptyTensor[float32](ort.NewShape(1, 1, 1, embedDim))
+	if err != nil {
+		return e, err
+	}
+	defer out.Destroy()
+	if err := m.emb.Run([]ort.Value{in}, []ort.Value{out}); err != nil {
+		return e, err
+	}
+	copy(e[:], out.GetData())
+	return e, nil
+}
+
+// score runs the trained head over headWindow embeddings.
+func (m *wakeModels) score(embeds [][embedDim]float32) (float64, error) {
+	flat := make([]float32, 0, headWindow*embedDim)
+	for _, e := range embeds {
+		flat = append(flat, e[:]...)
+	}
+	in, err := ort.NewTensor(ort.NewShape(1, headWindow, embedDim), flat)
+	if err != nil {
+		return 0, err
+	}
+	defer in.Destroy()
+	out, err := ort.NewEmptyTensor[float32](ort.NewShape(1, 1))
+	if err != nil {
+		return 0, err
+	}
+	defer out.Destroy()
+	if err := m.head.Run([]ort.Value{in}, []ort.Value{out}); err != nil {
+		return 0, err
+	}
+	return float64(out.GetData()[0]), nil
+}