diff --git a/extensions/git/scripts/bash/create-new-feature.sh b/extensions/git/scripts/bash/create-new-feature.sh
index 0df4adc3..b2d06564 100644
--- a/extensions/git/scripts/bash/create-new-feature.sh
+++ b/extensions/git/scripts/bash/create-new-feature.sh
@@ -175,7 +175,21 @@ clean_branch_name() {
 # to searching for repository markers so the workflow still functions in repositories that
 # were initialised with --no-git.
 SCRIPT_DIR="$(CDPATH="" cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-source "$SCRIPT_DIR/common.sh"
+
+# Source common.sh: try the core scripts directory first (standard layout),
+# then fall back to the extension's sibling copy.
+if [ -f "$SCRIPT_DIR/common.sh" ]; then
+    source "$SCRIPT_DIR/common.sh"
+else
+    # When running from an extension install (.specify/extensions/git/scripts/bash/),
+    # resolve common.sh from the project's core scripts directory.
+    _ext_repo_root="$(cd "$SCRIPT_DIR/../../../../.." 2>/dev/null && pwd)"
+    if [ -f "$_ext_repo_root/scripts/bash/common.sh" ]; then
+        source "$_ext_repo_root/scripts/bash/common.sh"
+    elif [ -f "$SCRIPT_DIR/git-common.sh" ]; then
+        source "$SCRIPT_DIR/git-common.sh"
+    fi
+fi
 
 if git rev-parse --show-toplevel >/dev/null 2>&1; then
     REPO_ROOT=$(git rev-parse --show-toplevel)
diff --git a/extensions/git/scripts/powershell/create-new-feature.ps1 b/extensions/git/scripts/powershell/create-new-feature.ps1
index 473c925b..76831d3a 100644
--- a/extensions/git/scripts/powershell/create-new-feature.ps1
+++ b/extensions/git/scripts/powershell/create-new-feature.ps1
@@ -145,8 +145,22 @@ if (-not $fallbackRoot) {
     exit 1
 }
 
-# Load common functions (includes Resolve-Template)
-. "$PSScriptRoot/common.ps1"
+# Load common functions (includes Resolve-Template).
+# Try the core scripts directory first (standard layout), then fall back
+# to the extension's sibling copy.
+if (Test-Path "$PSScriptRoot/common.ps1") {
+    . "$PSScriptRoot/common.ps1"
+} else {
+    # When running from an extension install (.specify/extensions/git/scripts/powershell/),
+    # resolve common.ps1 from the project's core scripts directory.
+    $extRepoRoot = (Resolve-Path (Join-Path $PSScriptRoot "../../../../..") -ErrorAction SilentlyContinue)
+    $coreCommon = if ($extRepoRoot) { Join-Path $extRepoRoot "scripts/powershell/common.ps1" } else { "" }
+    if ($coreCommon -and (Test-Path $coreCommon)) {
+        . $coreCommon
+    } elseif (Test-Path "$PSScriptRoot/git-common.ps1") {
+        . "$PSScriptRoot/git-common.ps1"
+    }
+}
 
 try {
     $repoRoot = git rev-parse --show-toplevel 2>$null