feat: GPU detection transparency and artifact scanner improvements

- Surface GPUDetectionInfo from parseGPUCountFromConfig for detection metadata
- Document FETCH_ML_TOTAL_CPU and FETCH_ML_GPU_SLOTS_PER_GPU env vars
- Add debug logging for all env var overrides to stderr
- Track config-layer auto-detection in GPUDetectionInfo.ConfigLayerAutoDetected
- Add --include-all flag to artifact scanner (includeAll parameter)
- Add AMD production mode enforcement (error in non-local mode)
- Add GPU detector unit tests for env overrides and AMD aliasing

.forgejo/workflows/ci.yml

@@ -334,6 +334,62 @@ jobs:
           echo "=== Native Implementation ==="
           CGO_ENABLED=1 go test -tags native_libs -bench=. ./tests/benchmarks/ -benchmem || true
 
+  test-gpu-matrix:
+    name: GPU Golden Test Matrix
+    runs-on: self-hosted
+    needs: test-native
+    timeout-minutes: 15
+    strategy:
+      matrix:
+        build_config: [cgo-native, cgo-only, nocgo]
+      fail-fast: false
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+
+      - name: Setup Go
+        run: |
+          REQUIRED_GO="1.25.0"
+          if command -v go &> /dev/null && go version | grep -q "go${REQUIRED_GO}"; then
+            echo "Go ${REQUIRED_GO} already installed"
+          else
+            echo "Installing Go ${REQUIRED_GO}..."
+            curl -sL "https://go.dev/dl/go${REQUIRED_GO}.linux-amd64.tar.gz" | sudo tar -C /usr/local -xzf -
+            export PATH="/usr/local/go/bin:$PATH"
+            echo "/usr/local/go/bin" >> $GITHUB_PATH
+          fi
+          go version
+
+      - name: Build Native Libraries (for cgo-native config)
+        if: matrix.build_config == 'cgo-native'
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y cmake zlib1g-dev build-essential
+          make native-build || echo "Native build skipped (may fail without proper deps)"
+
+      - name: Run GPU Tests - cgo+native_libs
+        if: matrix.build_config == 'cgo-native'
+        run: |
+          echo "=== Testing cgo + native_libs build ==="
+          CGO_ENABLED=1 go test -tags native_libs -v ./tests/unit/gpu/ -run TestGoldenGPUStatus
+          CGO_ENABLED=1 go test -tags native_libs -v ./tests/unit/gpu/ -run TestBuildTagMatrix
+
+      - name: Run GPU Tests - cgo only (no native_libs)
+        if: matrix.build_config == 'cgo-only'
+        run: |
+          echo "=== Testing cgo without native_libs build ==="
+          CGO_ENABLED=1 go test -v ./tests/unit/gpu/ -run TestGoldenGPUStatus
+          CGO_ENABLED=1 go test -v ./tests/unit/gpu/ -run TestBuildTagMatrix
+
+      - name: Run GPU Tests - nocgo
+        if: matrix.build_config == 'nocgo'
+        run: |
+          echo "=== Testing !cgo build ==="
+          CGO_ENABLED=0 go test -v ./tests/unit/gpu/ -run TestGoldenGPUStatus
+          CGO_ENABLED=0 go test -v ./tests/unit/gpu/ -run TestBuildTagMatrix
+
   docker-build:
     name: Docker Build
     runs-on: self-hosted

cli/src/utils/parallel_walk.zig

@@ -13,7 +13,7 @@ const WorkQueue = struct {
         depth: usize,
     };
 
-    fn init(allocator: std.mem.Allocator) WorkQueue {
+    fn init() WorkQueue {
         return .{
             .items = .empty,
             .mutex = .{},

docs/src/configuration-reference.md

@@ -321,6 +321,14 @@ api_key = "<analyst-api-key>"
 | `FETCHML_CONFIG` | - | Path to config file |
 | `FETCHML_LOG_LEVEL` | "info" | Override log level |
 | `CLI_CONFIG` | - | Path to CLI config file |
+| `FETCH_ML_GPU_TYPE` | - | Override GPU vendor detection (nvidia, amd, apple, none). Takes precedence over config file. |
+| `FETCH_ML_GPU_COUNT` | - | Override GPU count detection. Used with auto-detected or configured vendor. |
+| `FETCH_ML_TOTAL_CPU` | - | Override total CPU count detection. Sets the number of CPU cores available. |
+| `FETCH_ML_GPU_SLOTS_PER_GPU` | 1 | Override GPU slots per GPU. Controls how many concurrent tasks can share a single GPU. |
+
+When environment variable overrides are active, they are logged to stderr at worker startup for debugging.
+
+Note: When `gpu_vendor: amd` is configured, the system uses the NVIDIA detector implementation (aliased) due to similar device exposure patterns. The `configured_vendor` field will show "amd" while the actual detection uses NVIDIA-compatible methods.
 
 ## Troubleshooting
 

internal/worker/artifacts.go

@@ -11,7 +11,7 @@ import (
 	"github.com/jfraeys/fetch_ml/internal/manifest"
 )
 
-func scanArtifacts(runDir string) (*manifest.Artifacts, error) {
+func scanArtifacts(runDir string, includeAll bool) (*manifest.Artifacts, error) {
 	runDir = strings.TrimSpace(runDir)
 	if runDir == "" {
 		return nil, fmt.Errorf("run dir is empty")
@@ -37,19 +37,7 @@ func scanArtifacts(runDir string) (*manifest.Artifacts, error) {
 		}
 		rel = filepath.ToSlash(rel)
 
-		if rel == "code" || strings.HasPrefix(rel, "code/") {
-			if d.IsDir() {
-				return fs.SkipDir
-			}
-			return nil
-		}
-		if rel == "snapshot" || strings.HasPrefix(rel, "snapshot/") {
-			if d.IsDir() {
-				return fs.SkipDir
-			}
-			return nil
-		}
-
+		// Standard exclusions (always apply)
 		if rel == manifestFilename {
 			return nil
 		}
@@ -57,12 +45,26 @@ func scanArtifacts(runDir string) (*manifest.Artifacts, error) {
 			return nil
 		}
 
-		if strings.HasSuffix(rel, ".log") {
-			return nil
-		}
-
-		if d.Type()&fs.ModeSymlink != 0 {
-			return nil
+		// Optional exclusions (skipped when includeAll is true)
+		if !includeAll {
+			if rel == "code" || strings.HasPrefix(rel, "code/") {
+				if d.IsDir() {
+					return fs.SkipDir
+				}
+				return nil
+			}
+			if rel == "snapshot" || strings.HasPrefix(rel, "snapshot/") {
+				if d.IsDir() {
+					return fs.SkipDir
+				}
+				return nil
+			}
+			if strings.HasSuffix(rel, ".log") {
+				return nil
+			}
+			if d.Type()&fs.ModeSymlink != 0 {
+				return nil
+			}
 		}
 
 		if d.IsDir() {
@@ -100,6 +102,7 @@ func scanArtifacts(runDir string) (*manifest.Artifacts, error) {
 const manifestFilename = "run_manifest.json"
 
 // ScanArtifacts is an exported wrapper for testing/benchmarking.
-func ScanArtifacts(runDir string) (*manifest.Artifacts, error) {
-	return scanArtifacts(runDir)
+// When includeAll is false, excludes code/, snapshot/, *.log files, and symlinks.
+func ScanArtifacts(runDir string, includeAll bool) (*manifest.Artifacts, error) {
+	return scanArtifacts(runDir, includeAll)
 }

internal/worker/config.go

@@ -77,13 +77,14 @@ type Config struct {
 	PrewarmEnabled bool `yaml:"prewarm_enabled"`
 
 	// Podman execution
-	PodmanImage         string   `yaml:"podman_image"`
-	ContainerWorkspace  string   `yaml:"container_workspace"`
-	ContainerResults    string   `yaml:"container_results"`
-	GPUDevices          []string `yaml:"gpu_devices"`
-	GPUVendor           string   `yaml:"gpu_vendor"`
-	GPUVisibleDevices   []int    `yaml:"gpu_visible_devices"`
-	GPUVisibleDeviceIDs []string `yaml:"gpu_visible_device_ids"`
+	PodmanImage           string   `yaml:"podman_image"`
+	ContainerWorkspace    string   `yaml:"container_workspace"`
+	ContainerResults      string   `yaml:"container_results"`
+	GPUDevices            []string `yaml:"gpu_devices"`
+	GPUVendor             string   `yaml:"gpu_vendor"`
+	GPUVendorAutoDetected bool     `yaml:"-"` // Set by LoadConfig when GPUVendor is auto-detected
+	GPUVisibleDevices     []int    `yaml:"gpu_visible_devices"`
+	GPUVisibleDeviceIDs   []string `yaml:"gpu_visible_device_ids"`
 
 	// Apple M-series GPU configuration
 	AppleGPU AppleGPUConfig `yaml:"apple_gpu"`
@@ -264,6 +265,7 @@ func LoadConfig(path string) (*Config, error) {
 	}
 
 	if strings.TrimSpace(cfg.GPUVendor) == "" {
+		cfg.GPUVendorAutoDetected = true
 		if cfg.AppleGPU.Enabled {
 			cfg.GPUVendor = string(GPUTypeApple)
 		} else if len(cfg.GPUDevices) > 0 ||
@@ -453,9 +455,15 @@ func envInt(name string) (int, bool) {
 	return n, true
 }
 
+// logEnvOverride logs environment variable overrides to stderr for debugging
+func logEnvOverride(name string, value interface{}) {
+	fmt.Fprintf(os.Stderr, "[env] %s=%v (override active)\n", name, value)
+}
+
 // parseCPUFromConfig determines total CPU from environment or config
 func parseCPUFromConfig(cfg *Config) int {
 	if n, ok := envInt("FETCH_ML_TOTAL_CPU"); ok && n >= 0 {
+		logEnvOverride("FETCH_ML_TOTAL_CPU", n)
 		return n
 	}
 	if cfg != nil {
@@ -471,11 +479,11 @@ func parseCPUFromConfig(cfg *Config) int {
 	return runtime.NumCPU()
 }
 
-// parseGPUCountFromConfig detects GPU count from config
-func parseGPUCountFromConfig(cfg *Config) int {
+// parseGPUCountFromConfig detects GPU count from config and returns detection metadata
+func parseGPUCountFromConfig(cfg *Config) (int, GPUDetectionInfo) {
 	factory := &GPUDetectorFactory{}
-	detector := factory.CreateDetector(cfg)
-	return detector.DetectGPUCount()
+	result := factory.CreateDetectorWithInfo(cfg)
+	return result.Detector.DetectGPUCount(), result.Info
 }
 
 // parseGPUSlotsPerGPUFromConfig reads GPU slots per GPU from environment

internal/worker/factory.go

@@ -147,9 +147,10 @@ func NewWorker(cfg *Config, _ string) (*Worker, error) {
 	)
 
 	// Create resource manager
+	gpuCount, gpuDetectionInfo := parseGPUCountFromConfig(cfg)
 	rm, err := resources.NewManager(resources.Options{
 		TotalCPU:    parseCPUFromConfig(cfg),
-		GPUCount:    parseGPUCountFromConfig(cfg),
+		GPUCount:    gpuCount,
 		SlotsPerGPU: parseGPUSlotsPerGPUFromConfig(),
 	})
 	if err != nil {
@@ -158,28 +159,32 @@ func NewWorker(cfg *Config, _ string) (*Worker, error) {
 	}
 
 	worker := &Worker{
-		id:        cfg.WorkerID,
-		config:    cfg,
-		logger:    logger,
-		runLoop:   runLoop,
-		runner:    jobRunner,
-		metrics:   metricsObj,
-		health:    lifecycle.NewHealthMonitor(),
-		resources: rm,
-		jupyter:   jupyterMgr,
+		id:               cfg.WorkerID,
+		config:           cfg,
+		logger:           logger,
+		runLoop:          runLoop,
+		runner:           jobRunner,
+		metrics:          metricsObj,
+		health:           lifecycle.NewHealthMonitor(),
+		resources:        rm,
+		jupyter:          jupyterMgr,
+		gpuDetectionInfo: gpuDetectionInfo,
 	}
 
 	// Log GPU configuration
 	if !cfg.LocalMode {
 		gpuType := strings.ToLower(strings.TrimSpace(os.Getenv("FETCH_ML_GPU_TYPE")))
-		if cfg.AppleGPU.Enabled {
-			logger.Warn("apple MPS GPU mode is intended for development; do not use in production",
-				"gpu_type", "apple",
-			)
-		}
 		if gpuType == "amd" {
-			logger.Warn("amd GPU mode is intended for development; do not use in production",
-				"gpu_type", "amd",
+			cancel()
+			return nil, fmt.Errorf(
+				"AMD GPU mode is not supported in production (FETCH_ML_GPU_TYPE=amd). " +
+					"Use 'nvidia', 'apple', 'none', or GPUDevices config. " +
+					"AMD support is available in local mode for experimental development",
+			)
+		} else if cfg.AppleGPU.Enabled {
+			logger.Warn(
+				"apple MPS GPU mode is intended for development; do not use in production",
+				"gpu_type", "apple",
 			)
 		}
 	}

internal/worker/gpu_detector.go

@@ -11,10 +11,33 @@ type GPUType string
 
 const (
 	GPUTypeNVIDIA GPUType = "nvidia"
+	GPUTypeAMD    GPUType = "amd"
 	GPUTypeApple  GPUType = "apple"
 	GPUTypeNone   GPUType = "none"
 )
 
+// DetectionSource indicates how the GPU detector was selected
+type DetectionSource string
+
+const (
+	DetectionSourceEnvType  DetectionSource = "env_override_type"
+	DetectionSourceEnvCount DetectionSource = "env_override_count"
+	DetectionSourceEnvBoth  DetectionSource = "env_override_both"
+	DetectionSourceConfig   DetectionSource = "config"
+	DetectionSourceAuto     DetectionSource = "auto"
+	DetectionSourceNone     DetectionSource = "none"
+)
+
+// GPUDetectionInfo provides metadata about how GPU detection was determined
+type GPUDetectionInfo struct {
+	GPUType                 GPUType         `json:"gpu_type"`
+	ConfiguredVendor        string          `json:"configured_vendor"`
+	DetectionMethod         DetectionSource `json:"detection_method"`
+	EnvOverrideType         string          `json:"env_override_type,omitempty"`
+	EnvOverrideCount        int             `json:"env_override_count,omitempty"`
+	ConfigLayerAutoDetected bool            `json:"config_layer_auto_detected,omitempty"`
+}
+
 // GPUDetector interface for detecting GPU availability
 type GPUDetector interface {
 	DetectGPUCount() int
@@ -138,47 +161,240 @@ func (d *NoneDetector) GetDevicePaths() []string {
 	return nil
 }
 
-// GPUDetectorFactory creates appropriate GPU detector based on config
+// GPUDetectorFactory creates appropriate GPU detector based config
 type GPUDetectorFactory struct{}
 
+// DetectionResult contains both the detector and metadata about how it was selected
+type DetectionResult struct {
+	Detector GPUDetector
+	Info     GPUDetectionInfo
+}
+
 func (f *GPUDetectorFactory) CreateDetector(cfg *Config) GPUDetector {
-	// Check for explicit environment override
-	if gpuType := os.Getenv("FETCH_ML_GPU_TYPE"); gpuType != "" {
-		switch gpuType {
+	result := f.CreateDetectorWithInfo(cfg)
+	return result.Detector
+}
+
+func (f *GPUDetectorFactory) CreateDetectorWithInfo(cfg *Config) DetectionResult {
+	// Check for explicit environment overrides
+	envType := os.Getenv("FETCH_ML_GPU_TYPE")
+	envCount, hasEnvCount := envInt("FETCH_ML_GPU_COUNT")
+
+	if envType != "" && hasEnvCount {
+		// Both env vars set
+		logEnvOverride("FETCH_ML_GPU_TYPE", envType)
+		logEnvOverride("FETCH_ML_GPU_COUNT", envCount)
+		switch envType {
 		case string(GPUTypeNVIDIA):
-			return &NVIDIADetector{}
+			return DetectionResult{
+				Detector: &NVIDIADetector{},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeNVIDIA,
+					ConfiguredVendor: "nvidia",
+					DetectionMethod:  DetectionSourceEnvBoth,
+					EnvOverrideType:  envType,
+					EnvOverrideCount: envCount,
+				},
+			}
 		case string(GPUTypeApple):
-			return &AppleDetector{enabled: true}
+			return DetectionResult{
+				Detector: &AppleDetector{enabled: true},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeApple,
+					ConfiguredVendor: "apple",
+					DetectionMethod:  DetectionSourceEnvBoth,
+					EnvOverrideType:  envType,
+					EnvOverrideCount: envCount,
+				},
+			}
 		case string(GPUTypeNone):
-			return &NoneDetector{}
-		}
-	}
-
-	// Respect configured vendor when explicitly set.
-	if cfg != nil {
-		switch GPUType(cfg.GPUVendor) {
-		case GPUTypeApple:
-			return &AppleDetector{enabled: cfg.AppleGPU.Enabled}
-		case GPUTypeNone:
-			return &NoneDetector{}
-		case GPUTypeNVIDIA:
-			return &NVIDIADetector{}
+			return DetectionResult{
+				Detector: &NoneDetector{},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeNone,
+					ConfiguredVendor: "none",
+					DetectionMethod:  DetectionSourceEnvBoth,
+					EnvOverrideType:  envType,
+					EnvOverrideCount: envCount,
+				},
+			}
 		case "amd":
-			// AMD uses similar device exposure patterns in this codebase.
-			return &NVIDIADetector{}
+			// AMD env override uses NVIDIA detector (aliased)
+			return DetectionResult{
+				Detector: &NVIDIADetector{},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeAMD,
+					ConfiguredVendor: "amd",
+					DetectionMethod:  DetectionSourceEnvBoth,
+					EnvOverrideType:  envType,
+					EnvOverrideCount: envCount,
+				},
+			}
 		}
 	}
 
-	// Auto-detect based on config
-	if cfg != nil {
-		if cfg.AppleGPU.Enabled {
-			return &AppleDetector{enabled: true}
+	if envType != "" {
+		// Only FETCH_ML_GPU_TYPE set
+		logEnvOverride("FETCH_ML_GPU_TYPE", envType)
+		switch envType {
+		case string(GPUTypeNVIDIA):
+			return DetectionResult{
+				Detector: &NVIDIADetector{},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeNVIDIA,
+					ConfiguredVendor: "nvidia",
+					DetectionMethod:  DetectionSourceEnvType,
+					EnvOverrideType:  envType,
+				},
+			}
+		case string(GPUTypeApple):
+			return DetectionResult{
+				Detector: &AppleDetector{enabled: true},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeApple,
+					ConfiguredVendor: "apple",
+					DetectionMethod:  DetectionSourceEnvType,
+					EnvOverrideType:  envType,
+				},
+			}
+		case string(GPUTypeNone):
+			return DetectionResult{
+				Detector: &NoneDetector{},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeNone,
+					ConfiguredVendor: "none",
+					DetectionMethod:  DetectionSourceEnvType,
+					EnvOverrideType:  envType,
+				},
+			}
+		case "amd":
+			// AMD env override uses NVIDIA detector (aliased)
+			return DetectionResult{
+				Detector: &NVIDIADetector{},
+				Info: GPUDetectionInfo{
+					GPUType:          GPUTypeAMD,
+					ConfiguredVendor: "amd",
+					DetectionMethod:  DetectionSourceEnvType,
+					EnvOverrideType:  envType,
+				},
+			}
 		}
-		if len(cfg.GPUDevices) > 0 {
-			return &NVIDIADetector{}
+	}
+
+	if hasEnvCount {
+		// Only FETCH_ML_GPU_COUNT set - need to detect vendor from config or auto
+		logEnvOverride("FETCH_ML_GPU_COUNT", envCount)
+		return f.detectFromConfigWithSource(cfg, DetectionSourceEnvCount, "", envCount)
+	}
+
+	// No env overrides - detect from config
+	return f.detectFromConfigWithSource(cfg, DetectionSourceConfig, "", -1)
+}
+
+func (f *GPUDetectorFactory) detectFromConfigWithSource(cfg *Config, source DetectionSource, envType string, envCount int) DetectionResult {
+	if cfg == nil {
+		return DetectionResult{
+			Detector: &NoneDetector{},
+			Info: GPUDetectionInfo{
+				GPUType:          GPUTypeNone,
+				ConfiguredVendor: "none",
+				DetectionMethod:  source,
+			},
+		}
+	}
+
+	switch GPUType(cfg.GPUVendor) {
+	case GPUTypeApple:
+		return DetectionResult{
+			Detector: &AppleDetector{enabled: cfg.AppleGPU.Enabled},
+			Info: GPUDetectionInfo{
+				GPUType:                 GPUTypeApple,
+				ConfiguredVendor:        "apple",
+				DetectionMethod:         source,
+				EnvOverrideType:         envType,
+				EnvOverrideCount:        envCount,
+				ConfigLayerAutoDetected: cfg.GPUVendorAutoDetected,
+			},
+		}
+	case GPUTypeNone:
+		return DetectionResult{
+			Detector: &NoneDetector{},
+			Info: GPUDetectionInfo{
+				GPUType:                 GPUTypeNone,
+				ConfiguredVendor:        "none",
+				DetectionMethod:         source,
+				EnvOverrideType:         envType,
+				EnvOverrideCount:        envCount,
+				ConfigLayerAutoDetected: cfg.GPUVendorAutoDetected,
+			},
+		}
+	case GPUTypeNVIDIA:
+		return DetectionResult{
+			Detector: &NVIDIADetector{},
+			Info: GPUDetectionInfo{
+				GPUType:                 GPUTypeNVIDIA,
+				ConfiguredVendor:        "nvidia",
+				DetectionMethod:         source,
+				EnvOverrideType:         envType,
+				EnvOverrideCount:        envCount,
+				ConfigLayerAutoDetected: cfg.GPUVendorAutoDetected,
+			},
+		}
+	case "amd":
+		// AMD uses similar device exposure patterns in this codebase.
+		// This is the key aliasing point - we report AMD as configured vendor
+		// but use NVIDIADetector for implementation.
+		return DetectionResult{
+			Detector: &NVIDIADetector{},
+			Info: GPUDetectionInfo{
+				GPUType:                 GPUTypeNVIDIA,
+				ConfiguredVendor:        "amd", // User configured "amd"
+				DetectionMethod:         source,
+				EnvOverrideType:         envType,
+				EnvOverrideCount:        envCount,
+				ConfigLayerAutoDetected: cfg.GPUVendorAutoDetected,
+			},
+		}
+	}
+
+	// Auto-detect based on config settings
+	if cfg.AppleGPU.Enabled {
+		return DetectionResult{
+			Detector: &AppleDetector{enabled: true},
+			Info: GPUDetectionInfo{
+				GPUType:                 GPUTypeApple,
+				ConfiguredVendor:        "apple",
+				DetectionMethod:         DetectionSourceAuto,
+				EnvOverrideType:         envType,
+				EnvOverrideCount:        envCount,
+				ConfigLayerAutoDetected: cfg.GPUVendorAutoDetected,
+			},
+		}
+	}
+	if len(cfg.GPUDevices) > 0 {
+		return DetectionResult{
+			Detector: &NVIDIADetector{},
+			Info: GPUDetectionInfo{
+				GPUType:                 GPUTypeNVIDIA,
+				ConfiguredVendor:        "nvidia",
+				DetectionMethod:         DetectionSourceAuto,
+				EnvOverrideType:         envType,
+				EnvOverrideCount:        envCount,
+				ConfigLayerAutoDetected: cfg.GPUVendorAutoDetected,
+			},
 		}
 	}
 
 	// Default to no GPU
-	return &NoneDetector{}
+	return DetectionResult{
+		Detector: &NoneDetector{},
+		Info: GPUDetectionInfo{
+			GPUType:                 GPUTypeNone,
+			ConfiguredVendor:        "none",
+			DetectionMethod:         source,
+			EnvOverrideType:         envType,
+			EnvOverrideCount:        envCount,
+			ConfigLayerAutoDetected: cfg.GPUVendorAutoDetected,
+		},
+	}
 }

internal/worker/gpu_macos.go

@@ -8,6 +8,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"os"
 	"os/exec"
 	"regexp"
 	"runtime"
@@ -176,6 +177,9 @@ func GetPowermetricsData() (*PowermetricsData, error) {
 	out, err := cmd.Output()
 	if err != nil {
 		// powermetrics not available or no permission
+		if ctx.Err() != context.DeadlineExceeded {
+			fmt.Fprintln(os.Stderr, "Warning: powermetrics requires sudo for GPU metrics")
+		}
 		return &PowermetricsData{HasData: false}, nil
 	}
 

internal/worker/native_bridge_libs.go

@@ -26,6 +26,8 @@ var (
 	ctxInitTime time.Time
 )
 
+// getHashContext returns the native hash context, initializing it on first call.
+// First call initializes C++ context (5-20ms) - subsequent calls reuse context.
 func getHashContext() *C.fh_context_t {
 	hashCtxOnce.Do(func() {
 		start := time.Now()
@@ -65,7 +67,7 @@ func HasSIMDSHA256() bool {
 }
 
 func ScanArtifactsNative(runDir string) (*manifest.Artifacts, error) {
-	return ScanArtifacts(runDir)
+	return ScanArtifacts(runDir, false)
 }
 
 func ExtractTarGzNative(archivePath, dstDir string) error {

internal/worker/worker.go

@@ -55,6 +55,9 @@ type Worker struct {
 	health     *lifecycle.HealthMonitor
 	resources  *resources.Manager
 
+	// GPU detection metadata for status output
+	gpuDetectionInfo GPUDetectionInfo
+
 	// Legacy fields for backward compatibility during migration
 	jupyter     JupyterManager
 	queueClient queue.Backend // Stored for prewarming access

tests/benchmarks/artifact_and_snapshot_bench_test.go

@@ -131,7 +131,7 @@ func BenchmarkScanArtifacts(b *testing.B) {
 	b.ReportAllocs()
 
 	for i := 0; i < b.N; i++ {
-		_, err := worker.ScanArtifacts(runDir)
+		_, err := worker.ScanArtifacts(runDir, false)
 		if err != nil {
 			b.Fatal(err)
 		}

tests/benchmarks/artifact_scanner_bench_test.go

@@ -15,11 +15,10 @@ func BenchmarkArtifactScanGo(b *testing.B) {
 	// Create test artifact structure
 	createTestArtifacts(b, tmpDir, 100)
 
-	b.ResetTimer()
 	b.ReportAllocs()
 
-	for i := 0; i < b.N; i++ {
-		_, err := worker.ScanArtifacts(tmpDir)
+	for b.Loop() {
+		_, err := worker.ScanArtifacts(tmpDir, false)
 		if err != nil {
 			b.Fatal(err)
 		}
@@ -34,10 +33,9 @@ func BenchmarkArtifactScanNative(b *testing.B) {
 	// Create test artifact structure
 	createTestArtifacts(b, tmpDir, 100)
 
-	b.ResetTimer()
 	b.ReportAllocs()
 
-	for i := 0; i < b.N; i++ {
+	for b.Loop() {
 		_, err := worker.ScanArtifactsNative(tmpDir)
 		if err != nil {
 			b.Fatal(err)
@@ -54,8 +52,8 @@ func BenchmarkArtifactScanLarge(b *testing.B) {
 
 	b.Run("Go", func(b *testing.B) {
 		b.ReportAllocs()
-		for i := 0; i < b.N; i++ {
-			_, err := worker.ScanArtifacts(tmpDir)
+		for b.Loop() {
+			_, err := worker.ScanArtifacts(tmpDir, false)
 			if err != nil {
 				b.Fatal(err)
 			}
@@ -64,7 +62,7 @@ func BenchmarkArtifactScanLarge(b *testing.B) {
 
 	b.Run("Native", func(b *testing.B) {
 		b.ReportAllocs()
-		for i := 0; i < b.N; i++ {
+		for b.Loop() {
 			_, err := worker.ScanArtifactsNative(tmpDir)
 			if err != nil {
 				b.Fatal(err)
@@ -93,7 +91,7 @@ func createTestArtifacts(b testing.TB, root string, count int) {
 	}
 
 	// Create test files
-	for i := 0; i < count; i++ {
+	for i := range count {
 		var path string
 		switch i % 5 {
 		case 0:

tests/unit/gpu/gpu_detector_test.go

@@ -0,0 +1,210 @@
+package worker_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/jfraeys/fetch_ml/internal/worker"
+)
+
+// TestGPUDetectorEnvOverrides validates both FETCH_ML_GPU_TYPE and FETCH_ML_GPU_COUNT work
+func TestGPUDetectorEnvOverrides(t *testing.T) {
+	tests := []struct {
+		name            string
+		gpuType         string
+		gpuCount        string
+		wantType        worker.GPUType
+		wantCount       int
+		wantMethod      worker.DetectionSource
+		wantConfigured  string
+	}{
+		{
+			name:           "env type only - nvidia",
+			gpuType:        "nvidia",
+			wantType:       worker.GPUTypeNVIDIA,
+			wantMethod:     worker.DetectionSourceEnvType,
+			wantConfigured: "nvidia",
+		},
+		{
+			name:           "env type only - apple",
+			gpuType:        "apple",
+			wantType:       worker.GPUTypeApple,
+			wantMethod:     worker.DetectionSourceEnvType,
+			wantConfigured: "apple",
+		},
+		{
+			name:           "env type only - none",
+			gpuType:        "none",
+			wantType:       worker.GPUTypeNone,
+			wantMethod:     worker.DetectionSourceEnvType,
+			wantConfigured: "none",
+		},
+		{
+			name:           "both env vars set",
+			gpuType:        "nvidia",
+			gpuCount:       "4",
+			wantType:       worker.GPUTypeNVIDIA,
+			wantMethod:     worker.DetectionSourceEnvBoth,
+			wantConfigured: "nvidia",
+		},
+		{
+			name:           "env type amd - shows amd configured vendor",
+			gpuType:        "amd",
+			wantType:       worker.GPUTypeAMD,
+			wantMethod:     worker.DetectionSourceEnvType,
+			wantConfigured: "amd",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Set env vars
+			if tt.gpuType != "" {
+				os.Setenv("FETCH_ML_GPU_TYPE", tt.gpuType)
+				defer os.Unsetenv("FETCH_ML_GPU_TYPE")
+			}
+			if tt.gpuCount != "" {
+				os.Setenv("FETCH_ML_GPU_COUNT", tt.gpuCount)
+				defer os.Unsetenv("FETCH_ML_GPU_COUNT")
+			}
+
+			factory := &worker.GPUDetectorFactory{}
+			result := factory.CreateDetectorWithInfo(nil)
+
+			if result.Info.GPUType != tt.wantType {
+				t.Errorf("GPUType = %v, want %v", result.Info.GPUType, tt.wantType)
+			}
+			if result.Info.DetectionMethod != tt.wantMethod {
+				t.Errorf("DetectionMethod = %v, want %v", result.Info.DetectionMethod, tt.wantMethod)
+			}
+			if result.Info.ConfiguredVendor != tt.wantConfigured {
+				t.Errorf("ConfiguredVendor = %v, want %v", result.Info.ConfiguredVendor, tt.wantConfigured)
+			}
+		})
+	}
+}
+
+// TestGPUDetectorAMDVendorAlias validates AMD config shows proper aliasing
+func TestGPUDetectorAMDVendorAlias(t *testing.T) {
+	cfg := &worker.Config{
+		GPUVendor: "amd",
+	}
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(cfg)
+
+	// AMD uses NVIDIA detector implementation
+	if result.Info.ConfiguredVendor != "amd" {
+		t.Errorf("ConfiguredVendor = %v, want 'amd'", result.Info.ConfiguredVendor)
+	}
+	if result.Info.GPUType != worker.GPUTypeNVIDIA {
+		t.Errorf("GPUType = %v, want %v (NVIDIA implementation for AMD alias)", result.Info.GPUType, worker.GPUTypeNVIDIA)
+	}
+}
+
+// TestGPUDetectorEnvCountOverride validates FETCH_ML_GPU_COUNT with auto-detect
+func TestGPUDetectorEnvCountOverride(t *testing.T) {
+	os.Setenv("FETCH_ML_GPU_COUNT", "8")
+	defer os.Unsetenv("FETCH_ML_GPU_COUNT")
+
+	cfg := &worker.Config{
+		GPUVendor: "nvidia",
+	}
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(cfg)
+
+	if result.Info.DetectionMethod != worker.DetectionSourceEnvCount {
+		t.Errorf("DetectionMethod = %v, want %v", result.Info.DetectionMethod, worker.DetectionSourceEnvCount)
+	}
+	if result.Info.EnvOverrideCount != 8 {
+		t.Errorf("EnvOverrideCount = %v, want 8", result.Info.EnvOverrideCount)
+	}
+}
+
+// TestGPUDetectorDetectionSources validates all detection source types
+func TestGPUDetectorDetectionSources(t *testing.T) {
+	tests := []struct {
+		name       string
+		envType    string
+		envCount   string
+		config     *worker.Config
+		wantSource worker.DetectionSource
+	}{
+		{
+			name:       "env type takes precedence over config",
+			envType:    "apple",
+			config:     &worker.Config{GPUVendor: "nvidia"},
+			wantSource: worker.DetectionSourceEnvType,
+		},
+		{
+			name:       "env count triggers env_count source",
+			envCount:   "2",
+			config:     &worker.Config{GPUVendor: "nvidia"},
+			wantSource: worker.DetectionSourceEnvCount,
+		},
+		{
+			name:       "config source when no env",
+			config:     &worker.Config{GPUVendor: "nvidia"},
+			wantSource: worker.DetectionSourceConfig,
+		},
+		{
+			name:       "auto source for GPUDevices",
+			config:     &worker.Config{GPUDevices: []string{"/dev/nvidia0"}},
+			wantSource: worker.DetectionSourceAuto,
+		},
+		{
+			name:       "auto source for AppleGPU",
+			config:     &worker.Config{AppleGPU: worker.AppleGPUConfig{Enabled: true}},
+			wantSource: worker.DetectionSourceAuto,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if tt.envType != "" {
+				os.Setenv("FETCH_ML_GPU_TYPE", tt.envType)
+				defer os.Unsetenv("FETCH_ML_GPU_TYPE")
+			}
+			if tt.envCount != "" {
+				os.Setenv("FETCH_ML_GPU_COUNT", tt.envCount)
+				defer os.Unsetenv("FETCH_ML_GPU_COUNT")
+			}
+
+			factory := &worker.GPUDetectorFactory{}
+			result := factory.CreateDetectorWithInfo(tt.config)
+
+			if result.Info.DetectionMethod != tt.wantSource {
+				t.Errorf("DetectionMethod = %v, want %v", result.Info.DetectionMethod, tt.wantSource)
+			}
+		})
+	}
+}
+
+// TestGPUDetectorInfoFields validates all GPUDetectionInfo fields are populated
+func TestGPUDetectorInfoFields(t *testing.T) {
+	os.Setenv("FETCH_ML_GPU_TYPE", "nvidia")
+	os.Setenv("FETCH_ML_GPU_COUNT", "4")
+	defer os.Unsetenv("FETCH_ML_GPU_TYPE")
+	defer os.Unsetenv("FETCH_ML_GPU_COUNT")
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(nil)
+
+	// Validate all expected fields
+	if result.Info.GPUType == "" {
+		t.Error("GPUType field is empty")
+	}
+	if result.Info.ConfiguredVendor == "" {
+		t.Error("ConfiguredVendor field is empty")
+	}
+	if result.Info.DetectionMethod == "" {
+		t.Error("DetectionMethod field is empty")
+	}
+	if result.Info.EnvOverrideType != "nvidia" {
+		t.Errorf("EnvOverrideType = %v, want 'nvidia'", result.Info.EnvOverrideType)
+	}
+	if result.Info.EnvOverrideCount != 4 {
+		t.Errorf("EnvOverrideCount = %v, want 4", result.Info.EnvOverrideCount)
+	}
+}

tests/unit/gpu/gpu_golden_test.go

@@ -0,0 +1,311 @@
+package worker_test
+
+import (
+	"encoding/json"
+	"os"
+	"testing"
+
+	"github.com/jfraeys/fetch_ml/internal/worker"
+)
+
+// GoldenGPUStatus represents the expected GPU status output for golden file testing
+type GoldenGPUStatus struct {
+	GPUCount         int                    `json:"gpu_count"`
+	GPUType          string                 `json:"gpu_type"`
+	ConfiguredVendor string                 `json:"configured_vendor"`
+	DetectionMethod  string                 `json:"detection_method"`
+	EnvOverrideType  string                 `json:"env_override_type,omitempty"`
+	EnvOverrideCount int                    `json:"env_override_count,omitempty"`
+	BuildTags        map[string]bool        `json:"build_tags"`
+	NativeAvailable  bool                   `json:"native_available"`
+	Extra            map[string]interface{} `json:"extra,omitempty"`
+}
+
+// detectBuildTags returns which build tags are active
+func detectBuildTags() map[string]bool {
+	tags := map[string]bool{
+		"cgo":         false,
+		"native_libs": false,
+		"darwin":      false,
+		"linux":       false,
+	}
+
+	// CGO is determined at compile time - we can detect by trying to use native
+	// If native functions return "disabled", we know native_libs is not set
+	simdName := worker.GetSIMDImplName()
+	tags["native_libs"] = simdName != "disabled" && simdName != "disabled (no CGO)"
+	tags["cgo"] = simdName != "disabled (no CGO)"
+
+	// OS detection
+	if worker.IsMacOS() {
+		tags["darwin"] = true
+	} else {
+		tags["linux"] = true
+	}
+
+	return tags
+}
+
+// TestGoldenGPUStatusNVML validates GPU status against golden file for NVML path
+// This test runs under all build configurations but expectations differ:
+// - cgo+native_libs: Real GPU count and NVML detection
+// - cgo without native_libs: Returns 0, nil (stub behavior)
+// - !cgo: Returns 0, nil (stub behavior)
+func TestGoldenGPUStatusNVML(t *testing.T) {
+	// Setup: Configure for NVIDIA detection
+	cfg := &worker.Config{
+		GPUVendor: "nvidia",
+	}
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(cfg)
+
+	// Get actual detected count (behavior varies by build tags)
+	count := result.Detector.DetectGPUCount()
+
+	buildTags := detectBuildTags()
+
+	// Build the golden status object
+	got := GoldenGPUStatus{
+		GPUCount:         count,
+		GPUType:          string(result.Info.GPUType),
+		ConfiguredVendor: result.Info.ConfiguredVendor,
+		DetectionMethod:  string(result.Info.DetectionMethod),
+		BuildTags:        buildTags,
+		NativeAvailable:  buildTags["native_libs"] && buildTags["cgo"],
+	}
+
+	// Validate against build-specific expectations
+	if buildTags["native_libs"] && buildTags["cgo"] {
+		// Real NVML build: Should detect actual GPUs or get real NVML error
+		// GPU count may be 0 if no NVIDIA hardware, but detection method should be config
+		if got.DetectionMethod != "config" {
+			t.Errorf("cgo+native_libs: DetectionMethod = %v, want 'config'", got.DetectionMethod)
+		}
+	} else if buildTags["cgo"] {
+		// CGO without native_libs: Stub returns 0
+		if got.GPUCount != 0 {
+			t.Logf("cgo-only build: GPUCount = %d (expected 0 from stub)", got.GPUCount)
+		}
+		if got.NativeAvailable {
+			t.Error("cgo-only build: NativeAvailable should be false")
+		}
+	} else {
+		// No CGO: Stub returns 0
+		if got.GPUCount != 0 {
+			t.Logf("nocgo build: GPUCount = %d (expected 0 from stub)", got.GPUCount)
+		}
+		if got.NativeAvailable {
+			t.Error("nocgo build: NativeAvailable should be false")
+		}
+	}
+
+	// Common validations
+	if got.ConfiguredVendor != "nvidia" {
+		t.Errorf("ConfiguredVendor = %v, want 'nvidia'", got.ConfiguredVendor)
+	}
+}
+
+// TestGoldenGPUStatusAMDVendorAlias validates AMD aliasing is visible in output
+// Build tags: all three configurations
+// Runtime scenarios: amd config
+func TestGoldenGPUStatusAMDVendorAlias(t *testing.T) {
+	cfg := &worker.Config{
+		GPUVendor: "amd",
+	}
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(cfg)
+
+	buildTags := detectBuildTags()
+
+	got := GoldenGPUStatus{
+		GPUCount:         result.Detector.DetectGPUCount(),
+		GPUType:          string(result.Info.GPUType),
+		ConfiguredVendor: result.Info.ConfiguredVendor,
+		DetectionMethod:  string(result.Info.DetectionMethod),
+		BuildTags:        buildTags,
+		NativeAvailable:  buildTags["native_libs"] && buildTags["cgo"],
+	}
+
+	// The key assertion: configured_vendor should be "amd" but GPUType should be "nvidia"
+	// This makes the aliasing visible in status output
+	if got.ConfiguredVendor != "amd" {
+		t.Errorf("AMD config: ConfiguredVendor = %v, want 'amd'", got.ConfiguredVendor)
+	}
+	if got.GPUType != "nvidia" {
+		t.Errorf("AMD config: GPUType = %v, want 'nvidia' (AMD aliased to NVIDIA implementation)", got.GPUType)
+	}
+}
+
+// TestGoldenGPUStatusEnvOverride validates env override behavior across build configs
+// Build tags: all three
+// Runtime scenarios: env override set
+func TestGoldenGPUStatusEnvOverride(t *testing.T) {
+	// Set env override
+	os.Setenv("FETCH_ML_GPU_TYPE", "nvidia")
+	os.Setenv("FETCH_ML_GPU_COUNT", "4")
+	defer os.Unsetenv("FETCH_ML_GPU_TYPE")
+	defer os.Unsetenv("FETCH_ML_GPU_COUNT")
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(&worker.Config{GPUVendor: "apple"})
+
+	buildTags := detectBuildTags()
+
+	got := GoldenGPUStatus{
+		GPUCount:         result.Detector.DetectGPUCount(),
+		GPUType:          string(result.Info.GPUType),
+		ConfiguredVendor: result.Info.ConfiguredVendor,
+		DetectionMethod:  string(result.Info.DetectionMethod),
+		EnvOverrideType:  result.Info.EnvOverrideType,
+		EnvOverrideCount: result.Info.EnvOverrideCount,
+		BuildTags:        buildTags,
+	}
+
+	// Env should take precedence over config
+	if got.DetectionMethod != "env_override_both" {
+		t.Errorf("Env override: DetectionMethod = %v, want 'env_override_both'", got.DetectionMethod)
+	}
+	if got.GPUType != "nvidia" {
+		t.Errorf("Env override: GPUType = %v, want 'nvidia'", got.GPUType)
+	}
+	if got.EnvOverrideType != "nvidia" {
+		t.Errorf("Env override: EnvOverrideType = %v, want 'nvidia'", got.EnvOverrideType)
+	}
+	if got.EnvOverrideCount != 4 {
+		t.Errorf("Env override: EnvOverrideCount = %v, want 4", got.EnvOverrideCount)
+	}
+}
+
+// TestGoldenGPUStatusMacOS validates macOS detection when running on Darwin
+// Build tags: cgo+native_libs on Darwin
+// Runtime scenarios: darwin
+func TestGoldenGPUStatusMacOS(t *testing.T) {
+	if !worker.IsMacOS() {
+		t.Skip("Skipping macOS-specific test on non-Darwin platform")
+	}
+
+	cfg := &worker.Config{
+		GPUVendor: "apple",
+		AppleGPU:  worker.AppleGPUConfig{Enabled: true},
+	}
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(cfg)
+
+	buildTags := detectBuildTags()
+
+	got := GoldenGPUStatus{
+		GPUCount:         result.Detector.DetectGPUCount(),
+		GPUType:          string(result.Info.GPUType),
+		ConfiguredVendor: result.Info.ConfiguredVendor,
+		DetectionMethod:  string(result.Info.DetectionMethod),
+		BuildTags:        buildTags,
+		NativeAvailable:  buildTags["darwin"],
+	}
+
+	if got.ConfiguredVendor != "apple" {
+		t.Errorf("macOS: ConfiguredVendor = %v, want 'apple'", got.ConfiguredVendor)
+	}
+	if got.GPUType != "apple" {
+		t.Errorf("macOS: GPUType = %v, want 'apple'", got.GPUType)
+	}
+	if !got.BuildTags["darwin"] {
+		t.Error("macOS: darwin build tag should be true")
+	}
+}
+
+// TestGoldenGPUStatusNone validates no-GPU configuration
+// Build tags: all three
+// Runtime scenarios: none
+func TestGoldenGPUStatusNone(t *testing.T) {
+	cfg := &worker.Config{
+		GPUVendor: "none",
+	}
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(cfg)
+
+	if result.Detector.DetectGPUCount() != 0 {
+		t.Errorf("none config: GPUCount = %v, want 0", result.Detector.DetectGPUCount())
+	}
+	if result.Info.ConfiguredVendor != "none" {
+		t.Errorf("none config: ConfiguredVendor = %v, want 'none'", result.Info.ConfiguredVendor)
+	}
+}
+
+// TestGoldenJSONSerialization validates the GPU status serializes to JSON correctly
+func TestGoldenJSONSerialization(t *testing.T) {
+	os.Setenv("FETCH_ML_GPU_TYPE", "nvidia")
+	os.Setenv("FETCH_ML_GPU_COUNT", "2")
+	defer os.Unsetenv("FETCH_ML_GPU_TYPE")
+	defer os.Unsetenv("FETCH_ML_GPU_COUNT")
+
+	factory := &worker.GPUDetectorFactory{}
+	result := factory.CreateDetectorWithInfo(nil)
+
+	status := GoldenGPUStatus{
+		GPUCount:         result.Detector.DetectGPUCount(),
+		GPUType:          string(result.Info.GPUType),
+		ConfiguredVendor: result.Info.ConfiguredVendor,
+		DetectionMethod:  string(result.Info.DetectionMethod),
+		EnvOverrideType:  result.Info.EnvOverrideType,
+		EnvOverrideCount: result.Info.EnvOverrideCount,
+		BuildTags:        detectBuildTags(),
+	}
+
+	// Serialize to JSON (this mimics what ml status --json would output)
+	jsonData, err := json.MarshalIndent(status, "", "  ")
+	if err != nil {
+		t.Fatalf("JSON serialization failed: %v", err)
+	}
+
+	// Verify JSON can be parsed back
+	var parsed GoldenGPUStatus
+	if err := json.Unmarshal(jsonData, &parsed); err != nil {
+		t.Fatalf("JSON deserialization failed: %v", err)
+	}
+
+	if parsed.ConfiguredVendor != status.ConfiguredVendor {
+		t.Errorf("JSON roundtrip: ConfiguredVendor mismatch")
+	}
+	if parsed.DetectionMethod != status.DetectionMethod {
+		t.Errorf("JSON roundtrip: DetectionMethod mismatch")
+	}
+}
+
+// TestBuildTagMatrix validates that all expected build tag combinations are testable
+// This test documents the three build configurations:
+// 1. cgo + native_libs: Real native library implementations
+// 2. cgo without native_libs: Stubs that return errors
+// 3. !cgo: Stubs that return "disabled (no CGO)"
+func TestBuildTagMatrix(t *testing.T) {
+	tags := detectBuildTags()
+
+	// Log the current build configuration for CI visibility
+	t.Logf("Build configuration: cgo=%v native_libs=%v darwin=%v linux=%v",
+		tags["cgo"], tags["native_libs"], tags["darwin"], tags["linux"])
+
+	// Validate SIMD implementation name matches build tags
+	simdName := worker.GetSIMDImplName()
+	t.Logf("SIMD implementation: %s", simdName)
+
+	switch {
+	case tags["native_libs"]:
+		// Should have real implementation name (avx2, sha_ni, armv8_crypto, or generic)
+		if simdName == "disabled" || simdName == "disabled (no CGO)" {
+			t.Errorf("native_libs build: SIMD impl should be active, got %q", simdName)
+		}
+	case tags["cgo"]:
+		// Should be disabled without native_libs
+		if simdName != "disabled" {
+			t.Errorf("cgo-only build: SIMD impl should be 'disabled', got %q", simdName)
+		}
+	default:
+		// No CGO
+		if simdName != "disabled (no CGO)" {
+			t.Errorf("nocgo build: SIMD impl should be 'disabled (no CGO)', got %q", simdName)
+		}
+	}
+}

tests/unit/worker/artifacts_test.go

@@ -30,7 +30,7 @@ func TestScanArtifacts_SkipsKnownPathsAndLogs(t *testing.T) {
 	mustWrite("checkpoints/best.pt", []byte("checkpoint"))
 	mustWrite("plots/loss.png", []byte("png"))
 
-	art, err := worker.ScanArtifacts(runDir)
+	art, err := worker.ScanArtifacts(runDir, false)
 	if err != nil {
 		t.Fatalf("scanArtifacts: %v", err)
 	}