v2: add embedding tests, multilingual embedding support

Scripts/com.markbase.12b.plist

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>Label</key>
+    <string>com.markbase.12b</string>
+    <key>ProgramArguments</key>
+    <array>
+        <string>/Users/accusys/MarkBaseEngine/.build/arm64-apple-macosx/release/MarkBaseServer</string>
+        <string>gemma-4-12b-it-4bit</string>
+        <string>8081</string>
+    </array>
+    <key>RunAtLoad</key>
+    <true/>
+    <key>KeepAlive</key>
+    <true/>
+    <key>StandardOutPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/12b.log</string>
+    <key>StandardErrorPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/12b.log</string>
+    <key>WorkingDirectory</key>
+    <string>/Users/accusys/MarkBaseEngine</string>
+</dict>
+</plist>

Scripts/com.markbase.26b.plist

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>Label</key>
+    <string>com.markbase.26b</string>
+    <key>ProgramArguments</key>
+    <array>
+        <string>/Users/accusys/MarkBaseEngine/.build/arm64-apple-macosx/release/MarkBaseServer</string>
+        <string>gemma-4-26b-standard</string>
+        <string>8082</string>
+    </array>
+    <key>RunAtLoad</key>
+    <true/>
+    <key>KeepAlive</key>
+    <true/>
+    <key>StandardOutPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/26b.log</string>
+    <key>StandardErrorPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/26b.log</string>
+    <key>WorkingDirectory</key>
+    <string>/Users/accusys/MarkBaseEngine</string>
+</dict>
+</plist>

Scripts/com.markbase.31b.plist

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>Label</key>
+    <string>com.markbase.31b</string>
+    <key>ProgramArguments</key>
+    <array>
+        <string>/Users/accusys/MarkBaseEngine/.build/arm64-apple-macosx/release/MarkBaseServer</string>
+        <string>gemma-4-31b-it-4bit</string>
+        <string>8083</string>
+    </array>
+    <key>RunAtLoad</key>
+    <true/>
+    <key>KeepAlive</key>
+    <true/>
+    <key>StandardOutPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/31b.log</string>
+    <key>StandardErrorPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/31b.log</string>
+    <key>WorkingDirectory</key>
+    <string>/Users/accusys/MarkBaseEngine</string>
+</dict>
+</plist>

Scripts/com.markbase.e4b.plist

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>Label</key>
+    <string>com.markbase.e4b</string>
+    <key>ProgramArguments</key>
+    <array>
+        <string>/Users/accusys/MarkBaseEngine/.build/arm64-apple-macosx/release/MarkBaseServer</string>
+        <string>E4B-MarkBase</string>
+        <string>8080</string>
+    </array>
+    <key>RunAtLoad</key>
+    <true/>
+    <key>KeepAlive</key>
+    <true/>
+    <key>StandardOutPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/e4b.log</string>
+    <key>StandardErrorPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/e4b.log</string>
+    <key>WorkingDirectory</key>
+    <string>/Users/accusys/MarkBaseEngine</string>
+</dict>
+</plist>

Scripts/com.markbase.embedding.plist

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>Label</key>
+    <string>com.markbase.embedding</string>
+    <key>ProgramArguments</key>
+    <array>
+        <string>/Users/accusys/MarkBaseEngine/.build/arm64-apple-macosx/release/MarkBaseServer</string>
+        <string>E4B-MarkBase</string>
+        <string>8084</string>
+    </array>
+    <key>RunAtLoad</key>
+    <true/>
+    <key>KeepAlive</key>
+    <true/>
+    <key>StandardOutPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/embedding.log</string>
+    <key>StandardErrorPath</key>
+    <string>/Users/accusys/MarkBaseEngine/logs/embedding.log</string>
+    <key>WorkingDirectory</key>
+    <string>/Users/accusys/MarkBaseEngine</string>
+</dict>
+</plist>

Scripts/setup-servers.sh

@@ -0,0 +1,53 @@
+#!/bin/bash
+# Setup MarkBase model servers as launchd services
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+LAUNCH_AGENTS="$HOME/Library/LaunchAgents"
+LOG_DIR="/Users/accusys/MarkBaseEngine/logs"
+
+echo "Setting up MarkBase model servers..."
+
+# Create logs directory
+mkdir -p "$LOG_DIR"
+
+# List of services to install
+SERVICES=(
+    "com.markbase.e4b.plist"
+    "com.markbase.12b.plist"
+    "com.markbase.26b.plist"
+    "com.markbase.31b.plist"
+    "com.markbase.embedding.plist"
+)
+
+for plist in "${SERVICES[@]}"; do
+    src="$SCRIPT_DIR/$plist"
+    dst="$LAUNCH_AGENTS/$plist"
+    
+    if [ ! -f "$src" ]; then
+        echo "  SKIP: $plist not found"
+        continue
+    fi
+    
+    # Copy to LaunchAgents
+    cp "$src" "$dst"
+    echo "  Installed: $plist"
+    
+    # Load the service (skip if already loaded)
+    label="${plist%.plist}"
+    if launchctl list | grep -q "$label"; then
+        echo "  Reloading: $label"
+        launchctl unload "$dst" 2>/dev/null || true
+    fi
+    launchctl load "$dst"
+    echo "  Loaded: $label"
+done
+
+echo ""
+echo "Done! Services:"
+echo "  E4B-MarkBase       → http://localhost:8080"
+echo "  gemma-4-12b-it-4bit → http://localhost:8081"
+echo "  gemma-4-26b        → http://localhost:8082"
+echo "  gemma-4-31b        → http://localhost:8083"
+echo "  Embedding (E4B)    → http://localhost:8084"

Sources/MarkBase/Embedding/EmbeddingGemmaConfig.swift

@@ -0,0 +1,34 @@
+import Foundation
+
+/// EmbeddingGemma model configuration
+public struct EmbeddingGemmaConfig: Codable {
+    public let hiddenSize: Int
+    public let numHiddenLayers: Int
+    public let vocabSize: Int
+    public let numAttentionHeads: Int
+    public let numKeyValueHeads: Int
+    public let headDim: Int
+    public let intermediateSize: Int
+    public let maxPositionEmbeddings: Int
+    public let slidingWindow: Int
+    public let rmsNormEps: Float
+    public let ropeTheta: Float
+    public let useBidirectionalAttention: Bool
+    public let layerTypes: [String]
+
+    enum CodingKeys: String, CodingKey {
+        case hiddenSize = "hidden_size"
+        case numHiddenLayers = "num_hidden_layers"
+        case vocabSize = "vocab_size"
+        case numAttentionHeads = "num_attention_heads"
+        case numKeyValueHeads = "num_key_value_heads"
+        case headDim = "head_dim"
+        case intermediateSize = "intermediate_size"
+        case maxPositionEmbeddings = "max_position_embeddings"
+        case slidingWindow = "sliding_window"
+        case rmsNormEps = "rms_norm_eps"
+        case ropeTheta = "rope_theta"
+        case useBidirectionalAttention = "use_bidirectional_attention"
+        case layerTypes = "layer_types"
+    }
+}

Sources/MarkBase/Layers/Layer.swift

@@ -976,10 +976,8 @@ func quantizedMatmulExpert(engine: MarkBaseEngine, cmdBuf: MTLCommandBuffer,
                         gate: MoEExpertGroup, up: MoEExpertGroup, down: MoEExpertGroup,
                         accum: MTLBuffer) throws -> Bool {
         guard let pso = try? engine.pipeline(named: "moe_mega_kernel") else { return false }
-        // Mega kernel supports only 4-bit router with groupSize=64 experts
         guard router.bits == 4 else { return false }
         let expertGroupSize = gate.expertInDim / gate.numGroups
-        guard expertGroupSize == 64 else { return false }
         let enc = cmdBuf.makeComputeCommandEncoder()!
         enc.setComputePipelineState(pso)
         enc.setBuffer(input, offset: 0, index: 0)
@@ -1011,6 +1009,8 @@ func quantizedMatmulExpert(engine: MarkBaseEngine, cmdBuf: MTLCommandBuffer,
         enc.setBytes(&rScale, length: MemoryLayout<Float>.size, index: 17)
         var topK = UInt32(topK)
         enc.setBytes(&topK, length: MemoryLayout<UInt32>.size, index: 18)
+        var groupSize = UInt32(expertGroupSize)
+        enc.setBytes(&groupSize, length: MemoryLayout<UInt32>.size, index: 19)
 
         let count = Int(max(hiddenSize, moeIntermediate))
         let logitStorage = Int(numExperts) + Int(topK) + Int(topK)

Sources/MarkBase/Metal/OptimizedKernels.metal

@@ -815,13 +815,14 @@ kernel void moe_mega_kernel(
     constant uint &numExperts       [[buffer(16)]],
     constant float &routerScale     [[buffer(17)]],
     constant uint &topK             [[buffer(18)]],
+    constant uint &groupSize        [[buffer(19)]],
     threadgroup float *shared_space [[threadgroup(0)]],
     uint gid [[thread_position_in_grid]],
     uint tid [[thread_position_in_threadgroup]],
     uint tgSize [[threads_per_threadgroup]]
 ) {
-    uint numGroupsIn = hiddenSize / 64;
+    uint numGroupsIn = hiddenSize / groupSize;
-    uint numGroupsOut = moeIntermediate / 64;
+    uint numGroupsOut = moeIntermediate / groupSize;
     uint packedPerIn = hiddenSize / 8;
     uint packedPerOut = moeIntermediate / 8;
 
@@ -841,10 +842,10 @@ kernel void moe_mega_kernel(
         for (uint g = 0; g < numGroupsIn; g++) {
             float scale = s_router[tid * numGroupsIn + g];
             float bias = b_router[tid * numGroupsIn + g];
-            uint wBase = tid * packedPerIn + g * 8;
+            uint wBase = tid * packedPerIn + g * (groupSize / 8);
-            uint xBase = g * 64;
+            uint xBase = g * groupSize;
 
-            for (uint p = 0; p < 8; p += 4) {
+            for (uint p = 0; p < groupSize / 8; p += 4) {
                 device uint4 *rPtr = (device uint4*)(&w_router[wBase + p]);
                 uint4 packed = *rPtr;
 
@@ -971,10 +972,10 @@ kernel void moe_mega_kernel(
                 float uScale = s_up[sUpBase + gid * numGroupsIn + g];
                 float uBias = b_up[sUpBase + gid * numGroupsIn + g];
 
-                uint wb = gid * packedPerIn + g * 8;
+                uint wb = gid * packedPerIn + g * (groupSize / 8);
-                uint xBase = g * 64;
+                uint xBase = g * groupSize;
 
-                for (uint p = 0; p < 8; p += 4) {
+                for (uint p = 0; p < groupSize / 8; p += 4) {
                     device uint4 *gPtr = (device uint4*)(&w_gate[wGateBase + wb + p]);
                     device uint4 *uPtr = (device uint4*)(&w_up[wUpBase + wb + p]);
                     uint4 gP = *gPtr;
@@ -1047,10 +1048,10 @@ kernel void moe_mega_kernel(
                 float scale = s_down[wDownBase + gid * numGroupsOut + g];
                 float bias = b_down[wDownBase + gid * numGroupsOut + g];
 
-                uint wb = gid * packedPerOut + g * 8;
+                uint wb = gid * packedPerOut + g * (groupSize / 8);
-                uint iBase = g * 64;
+                uint iBase = g * groupSize;
 
-                for (uint p = 0; p < 8; p += 4) {
+                for (uint p = 0; p < groupSize / 8; p += 4) {
                     device uint4 *wPtr = (device uint4*)(&w_down[wDownBase + wb + p]);
                     uint4 packed = *wPtr;
 

Sources/MarkBaseServer/SimpleServerApp.swift

@@ -23,6 +23,7 @@ struct SimpleServerApp {
         let model = try E4BModel(modelDir: modelPath, engine: engine, maxContextLength: 512)
         let tokenizer = try TokenizerFactory.load(modelDir: modelPath)
         let generator = StreamingGenerator(model: model, tokenizer: tokenizer, engine: engine)
+        let embeddingModel = try TextEmbeddingModel(modelDir: modelPath, engine: engine, config: TextEmbeddingConfig())
 
         print("✓ E4B loaded (\(model.numHiddenLayers) layers)")
 
@@ -175,7 +176,8 @@ struct SimpleServerApp {
                 "For multimodal (vision/audio) support, use the MarkBase Swift library directly",
                 "Streaming support is planned but not yet implemented",
                 "Function calling uses native Gemma 4 special tokens",
-                "Messages can include tool_calls (assistant) and tool responses (tool role) for multi-turn function calling"
+                "Messages can include tool_calls (assistant) and tool responses (tool role) for multi-turn function calling",
+                "Text embeddings available via /v1/embeddings endpoint (OpenAI-compatible)"
               ]
             }
             """
@@ -287,6 +289,73 @@ struct SimpleServerApp {
             }
         }
 
+        router.post("/v1/embeddings") { request, _ in
+            let buffer = try await request.body.collect(upTo: .max)
+            let data = Data(buffer: buffer)
+
+            guard let json = try JSONSerialization.jsonObject(with: data) as? [String: Any],
+                  let input = json["input"] else {
+                return "{\"error\":\"invalid request\",\"type\":\"invalid_request_error\",\"code\":400,\"message\":\"missing 'input' field\"}"
+            }
+
+            let modelId = (json["model"] as? String) ?? "e4b"
+            let encodingFormat = (json["encoding_format"] as? String) ?? "float"
+
+            let inputs: [String]
+            if let str = input as? String {
+                inputs = [str]
+            } else if let arr = input as? [String] {
+                inputs = arr
+            } else {
+                return "{\"error\":\"invalid request\",\"type\":\"invalid_request_error\",\"code\":400,\"message\":\"'input' must be string or array of strings\"}"
+            }
+
+            var embeddings: [[String: Any]] = []
+            for (i, text) in inputs.enumerated() {
+                let t0 = Date()
+                let embedding = try embeddingModel.embed(text: text)
+                let duration = Date().timeIntervalSince(t0)
+
+                let embeddingData: [String: Any]
+                if encodingFormat == "base64" {
+                    let base64 = embedding.withUnsafeBytes { Data($0).base64EncodedString() }
+                    embeddingData = [
+                        "object": "embedding",
+                        "index": i,
+                        "embedding": base64,
+                        "usage_ms": Int(duration * 1000)
+                    ]
+                } else {
+                    embeddingData = [
+                        "object": "embedding",
+                        "index": i,
+                        "embedding": embedding,
+                        "usage_ms": Int(duration * 1000)
+                    ]
+                }
+                embeddings.append(embeddingData)
+            }
+
+            let id = UUID().uuidString
+            let ts = Int(Date().timeIntervalSince1970)
+            let totalTokens = inputs.reduce(0) { $0 + tokenizer.encode(text: $1).count }
+
+            let response: [String: Any] = [
+                "id": id,
+                "object": "list",
+                "created": ts,
+                "model": modelId,
+                "data": embeddings,
+                "usage": [
+                    "prompt_tokens": totalTokens,
+                    "total_tokens": totalTokens
+                ]
+            ]
+
+            let jsonData = try JSONSerialization.data(withJSONObject: response)
+            return String(data: jsonData, encoding: .utf8) ?? "{}"
+        }
+
         let app = Application(
             router: router,
             configuration: .init(address: .hostname("0.0.0.0", port: port))
@@ -299,6 +368,7 @@ struct SimpleServerApp {
         print("  GET  /health   - Health check")
         print("  GET  /v1/models - Model list")
         print("  POST /v1/chat/completions - Chat completion")
+        print("  POST /v1/embeddings - Text embeddings")
         print("")
         print("Model: \(modelName)")
         if modelName.contains("E4B") {

Tests/01_Model/EmbeddingTest.swift

@@ -0,0 +1,80 @@
+import XCTest
+@testable import MarkBase
+
+final class EmbeddingTest: XCTestCase {
+    var engine: MarkBaseEngine!
+    var model: E4BModel!
+    var embeddingModel: TextEmbeddingModel!
+    let modelDir = "/Users/accusys/MarkBaseEngine/models/E4B-MarkBase"
+
+    override func setUp() {
+        super.setUp()
+        guard FileManager.default.fileExists(atPath: modelDir + "/model.safetensors") else {
+            return
+        }
+        engine = try? MarkBaseEngine(autoCompile: true)
+        model = try? E4BModel(modelDir: modelDir, engine: engine, maxContextLength: 512)
+        embeddingModel = try? TextEmbeddingModel(modelDir: modelDir, engine: engine, config: TextEmbeddingConfig())
+    }
+
+    func testEmbeddingDimension() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+        let embedding = try embeddingModel.embed(text: "Hello world")
+        XCTAssertEqual(embedding.count, 2560, "Embedding dimension should be 2560")
+    }
+
+    func testEmbeddingNormalized() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+        let embedding = try embeddingModel.embed(text: "Test text")
+        let norm = sqrt(embedding.reduce(0) { $0 + $1 * $1 })
+        XCTAssertEqual(norm, 1.0, accuracy: 0.001, "Embedding should be L2 normalized")
+    }
+
+    func testSimilarSentences() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+        let e1 = try embeddingModel.embed(text: "The cat is sitting on the mat")
+        let e2 = try embeddingModel.embed(text: "A cat rests on a rug")
+        let e3 = try embeddingModel.embed(text: "The stock market crashed today")
+
+        let sim12 = cosineSimilarity(e1, e2)
+        let sim13 = cosineSimilarity(e1, e3)
+        print("Similar(cat, cat): \(sim12)")
+        print("Similar(cat, stock): \(sim13)")
+        XCTAssertGreaterThan(sim12, sim13, "Similar sentences should have higher cosine similarity")
+    }
+
+    func testDifferentLengths() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+        let e1 = try embeddingModel.embed(text: "Hi")
+        let e2 = try embeddingModel.embed(text: "This is a much longer sentence with many words")
+        XCTAssertEqual(e1.count, e2.count, "Embeddings should have same dimension regardless of input length")
+        XCTAssertEqual(e1.count, 2560)
+    }
+
+    func testEmptyInput() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+        let embedding = try embeddingModel.embed(text: "")
+        XCTAssertEqual(embedding.count, 0, "Empty input should return empty embedding")
+    }
+
+    func testBatchEmbedding() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+        let texts = ["Hello", "World", "Test"]
+        let embeddings = try embeddingModel.embedBatch(texts: texts)
+        XCTAssertEqual(embeddings.count, 3)
+        for embedding in embeddings {
+            XCTAssertEqual(embedding.count, 2560)
+        }
+    }
+
+    private func cosineSimilarity(_ a: [Float], _ b: [Float]) -> Float {
+        guard a.count == b.count, !a.isEmpty else { return 0 }
+        var dot: Float = 0, normA: Float = 0, normB: Float = 0
+        for i in 0..<a.count {
+            dot += a[i] * b[i]
+            normA += a[i] * a[i]
+            normB += b[i] * b[i]
+        }
+        return dot / (sqrt(normA) * sqrt(normB))
+    }
+}

Tests/01_Model/MultilangEmbeddingTest.swift

@@ -0,0 +1,78 @@
+import XCTest
+@testable import MarkBase
+
+final class MultilangEmbeddingTest: XCTestCase {
+    var engine: MarkBaseEngine!
+    var embeddingModel: TextEmbeddingModel!
+    let modelDir = "/Users/accusys/MarkBaseEngine/models/E4B-MarkBase"
+
+    override func setUp() {
+        super.setUp()
+        guard FileManager.default.fileExists(atPath: modelDir + "/model.safetensors") else { return }
+        engine = try? MarkBaseEngine(autoCompile: true)
+        embeddingModel = try? TextEmbeddingModel(modelDir: modelDir, engine: engine, config: TextEmbeddingConfig())
+    }
+
+    func testMultilangEmbeddings() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+
+        let texts: [String: String] = [
+            "en": "The weather is beautiful today",
+            "zh": "今天天氣很好",
+            "ja": "今日は天気がいいです",
+            "ko": "오늘 날씨가 좋습니다",
+            "es": "El clima está hermoso hoy",
+            "fr": "Il fait beau aujourd'hui",
+            "de": "Das Wetter ist heute schön",
+            "ru": "Сегодня прекрасная погода",
+            "ar": "الطقس جميل اليوم",
+            "hi": "आज मौसम बहुत सुंदर है"
+        ]
+
+        var embeddings: [String: [Float]] = [:]
+        for (lang, text) in texts {
+            let emb = try embeddingModel.embed(text: text)
+            XCTAssertEqual(emb.count, 2560, "\(lang) embedding dimension")
+            let norm = sqrt(emb.reduce(0) { $0 + $1 * $1 })
+            XCTAssertEqual(norm, 1.0, accuracy: 0.001, "\(lang) embedding normalized")
+            embeddings[lang] = emb
+            print("\(lang): OK (norm=\(String(format: "%.4f", norm)))")
+        }
+
+        // Cross-language similarity (en-zh should be higher than en-ru for weather context)
+        let enEmb = embeddings["en"]!
+        let zhEmb = embeddings["zh"]!
+        let jaEmb = embeddings["ja"]!
+
+        let simEnZh = cosineSimilarity(enEmb, zhEmb)
+        let simEnJa = cosineSimilarity(enEmb, jaEmb)
+        print("EN-ZH similarity: \(String(format: "%.4f", simEnZh))")
+        print("EN-JA similarity: \(String(format: "%.4f", simEnJa))")
+    }
+
+    func testCrossLingualSemanticSimilarity() throws {
+        try XCTSkipIf(embeddingModel == nil, "Model not found")
+
+        // Same meaning, different languages
+        let enCat = try embeddingModel.embed(text: "The cat is sleeping")
+        let zhCat = try embeddingModel.embed(text: "貓在睡覺")
+        let enDog = try embeddingModel.embed(text: "The dog is running")
+
+        let simSame = cosineSimilarity(enCat, zhCat)
+        let simDiff = cosineSimilarity(enCat, enDog)
+        print("EN(cat) - ZH(cat): \(String(format: "%.4f", simSame))")
+        print("EN(cat) - EN(dog): \(String(format: "%.4f", simDiff))")
+        print("Cross-lingual > Same-lingual different topic: \(simSame > simDiff)")
+    }
+
+    private func cosineSimilarity(_ a: [Float], _ b: [Float]) -> Float {
+        guard a.count == b.count, !a.isEmpty else { return 0 }
+        var dot: Float = 0, normA: Float = 0, normB: Float = 0
+        for i in 0..<a.count {
+            dot += a[i] * b[i]
+            normA += a[i] * a[i]
+            normB += b[i] * b[i]
+        }
+        return dot / (sqrt(normA) * sqrt(normB))
+    }
+}

Tests/01_Model/Timing26BTest.swift

@@ -0,0 +1,33 @@
+import Foundation
+import XCTest
+
+@testable import MarkBase
+
+final class Timing26BTest: XCTestCase {
+    let modelDir = "/Users/accusys/MarkBaseEngine/models/gemma-4-26b-standard"
+    var engine: MarkBaseEngine!
+    var model: E4BModel!
+    let maxCtx = 128
+
+    override func setUp() {
+        super.setUp()
+        guard FileManager.default.fileExists(atPath: modelDir + "/model.safetensors") else {
+            return
+        }
+        let t0 = Date()
+        engine = try? MarkBaseEngine(autoCompile: true)
+        model = try? E4BModel(modelDir: modelDir, engine: engine, maxContextLength: maxCtx)
+        let loadTime = Date().timeIntervalSince(t0)
+        print("Total init: \(String(format: "%.1f", loadTime))s")
+    }
+
+    func testForwardTiming() throws {
+        try XCTSkipIf(model == nil, "26B model not found")
+        for i in 0..<5 {
+            let t = Date()
+            _ = try model.forward(tokenId: 100 + i, position: i)
+            let ft = Date().timeIntervalSince(t)
+            print("Forward \(i+1): \(String(format: "%.3f", ft))s")
+        }
+    }
+}