feat: Add git hooks to enforce universal binary builds and improve CPU metric calculation.

.gitignore

@@ -52,4 +52,4 @@ cmd/analyze/analyze
 cmd/status/status
 /status
 mole-analyze
-# Note: bin/analyze-go and bin/status-go are released binaries and should be tracked
+# Note: bin/analyze-go and bin/status-go are tracked as release binaries

CONTRIBUTING.md

@@ -5,6 +5,9 @@
 ```bash
 # Install development tools
 brew install shfmt shellcheck bats-core
+
+# Install git hooks (validates universal binaries)
+./scripts/setup-hooks.sh
 ```
 
 ## Development
@@ -154,7 +157,24 @@ Format: `[MODULE_NAME] message` output to stderr.
 - Format code with `gofmt -w ./cmd/...`
 - Run `go vet ./cmd/...` to check for issues
 - Build with `go build ./...` to verify all packages compile
-- Build universal binaries via `./scripts/build-status.sh` and `./scripts/build-analyze.sh`
+
+**Building Universal Binaries:**
+
+⚠️ **IMPORTANT**: Never use `go build` directly to create `bin/analyze-go` or `bin/status-go`!
+
+Mole must support both Intel and Apple Silicon Macs. Always use the build scripts:
+
+```bash
+# Build universal binaries (x86_64 + arm64)
+./scripts/build-analyze.sh
+./scripts/build-status.sh
+```
+
+For local development/testing, you can use:
+- `go run ./cmd/status` or `go run ./cmd/analyze` (quick iteration)
+- `go build ./cmd/status` (creates single-arch binary for testing)
+
+The pre-commit hook will prevent you from accidentally committing non-universal binaries.
 
 **Guidelines:**
 

cmd/status/metrics_cpu.go

@@ -31,7 +31,13 @@ func collectCPU() (CPUStatus, error) {
 		logical = 1
 	}
 
-	percents, err := cpu.Percent(cpuSampleInterval, true)
+	// Use two-call pattern for more reliable CPU measurements
+	// First call: initialize/store current CPU times
+	cpu.Percent(0, true)
+	// Wait for sampling interval
+	time.Sleep(cpuSampleInterval)
+	// Second call: get actual percentages based on difference
+	percents, err := cpu.Percent(0, true)
 	var totalPercent float64
 	perCoreEstimated := false
 	if err != nil || len(percents) == 0 {
@@ -247,10 +253,10 @@ func fallbackCPUUtilization(logical int) (float64, []float64, error) {
 		total = maxTotal
 	}
 
-	perCore := make([]float64, logical)
 	avg := total / float64(logical)
+	perCore := make([]float64, logical)
 	for i := range perCore {
 		perCore[i] = avg
 	}
-	return total, perCore, nil
+	return avg, perCore, nil
 }

scripts/build-analyze.sh

@@ -4,8 +4,6 @@
 
 set -euo pipefail
 
-export CGO_ENABLED=0
-
 cd "$(dirname "$0")/.."
 
 # Check if Go is installed

scripts/build-status.sh

@@ -4,8 +4,6 @@
 
 set -euo pipefail
 
-export CGO_ENABLED=0
-
 cd "$(dirname "$0")/.."
 
 if ! command -v go > /dev/null 2>&1; then

scripts/hooks/pre-commit

@@ -0,0 +1,68 @@
+#!/bin/bash
+# Pre-commit hook to ensure bin/analyze-go and bin/status-go are universal binaries
+
+set -e
+
+# ANSI color codes
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m' # No Color
+
+# Check if binaries are being committed
+binaries=()
+if git diff --cached --name-only | grep -q "^bin/analyze-go$"; then
+    binaries+=("bin/analyze-go")
+fi
+if git diff --cached --name-only | grep -q "^bin/status-go$"; then
+    binaries+=("bin/status-go")
+fi
+
+# If no binaries are being committed, exit early
+if [[ ${#binaries[@]} -eq 0 ]]; then
+    exit 0
+fi
+
+echo -e "${YELLOW}Checking compiled binaries...${NC}"
+
+# Verify each binary is a universal binary
+all_valid=true
+for binary in "${binaries[@]}"; do
+    if [[ ! -f "$binary" ]]; then
+        echo -e "${RED}✗ $binary not found${NC}"
+        all_valid=false
+        continue
+    fi
+
+    # Check if it's a universal binary
+    if file "$binary" | grep -q "Mach-O universal binary"; then
+        # Verify it contains both x86_64 and arm64
+        if lipo -info "$binary" 2>/dev/null | grep -q "x86_64 arm64"; then
+            echo -e "${GREEN}✓ $binary is a universal binary (x86_64 + arm64)${NC}"
+        elif lipo -info "$binary" 2>/dev/null | grep -q "arm64 x86_64"; then
+            echo -e "${GREEN}✓ $binary is a universal binary (x86_64 + arm64)${NC}"
+        else
+            echo -e "${RED}✗ $binary is missing required architectures${NC}"
+            lipo -info "$binary"
+            all_valid=false
+        fi
+    else
+        echo -e "${RED}✗ $binary is not a universal binary${NC}"
+        file "$binary"
+        all_valid=false
+    fi
+done
+
+if [[ "$all_valid" == "false" ]]; then
+    echo ""
+    echo -e "${RED}Commit rejected: binaries must be universal (x86_64 + arm64)${NC}"
+    echo ""
+    echo "To create universal binaries, run:"
+    echo "  ./scripts/build-analyze.sh"
+    echo "  ./scripts/build-status.sh"
+    echo ""
+    exit 1
+fi
+
+echo -e "${GREEN}All binaries verified!${NC}"
+exit 0

scripts/setup-hooks.sh

@@ -0,0 +1,28 @@
+#!/bin/bash
+# Install git hooks for Mole development
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+HOOKS_DIR="$REPO_ROOT/.git/hooks"
+
+if [[ ! -d "$REPO_ROOT/.git" ]]; then
+    echo "Error: Not in a git repository"
+    exit 1
+fi
+
+echo "Installing git hooks..."
+
+# Install pre-commit hook
+if [[ -f "$SCRIPT_DIR/hooks/pre-commit" ]]; then
+    cp "$SCRIPT_DIR/hooks/pre-commit" "$HOOKS_DIR/pre-commit"
+    chmod +x "$HOOKS_DIR/pre-commit"
+    echo "✓ Installed pre-commit hook (validates universal binaries)"
+fi
+
+echo ""
+echo "Git hooks installed successfully!"
+echo ""
+echo "The pre-commit hook will ensure that bin/analyze-go and bin/status-go"
+echo "are universal binaries (x86_64 + arm64) before allowing commits."