diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..313d06f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,30 @@
+# Processed LSL files (generated by Jenkins)
+processed_*.lsl
+
+# Build artifacts
+releases/
+*.zip
+
+# Jenkins and CI artifacts
+FUNCTIONS.md
+DEPLOYMENT_NOTES.txt
+
+# IDE and editor files
+.vscode/
+.idea/
+*.sublime-*
+*~
+.*.swp
+.*.swo
+
+# OS generated files
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+ehthumbs.db
+Thumbs.db
+
+# Log files
+*.log
diff --git a/Jenkinsfile b/Jenkinsfile
index 52f2f25..46367a2 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -49,8 +49,9 @@ pipeline {
             steps {
                 echo "🔄 Preprocessing LSL files..."
                 sh '''
+                    # Only process original source files, not already-processed ones
                     for file in *.lsl; do
-                        if [ -f "$file" ]; then
+                        if [ -f "$file" ] && [[ ! "$file" =~ ^processed_ ]]; then
                             echo "Processing $file..."
                             python3 ${LSL_TOOLS_PATH}/lsl_preprocessor.py "$file" "processed_$file"
                         fi