diff --git a/LICENSE b/LICENSE
index 85e643c..a545727 100644
--- a/LICENSE
+++ b/LICENSE
@@ -221,7 +221,7 @@ Also add information on how to contact you by electronic and paper mail.
 
 If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode:
 
-     ztl-mode  Copyright (C) 2025  zongor
+     ZRE  Copyright (C) 2025  zongor
      This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
      This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details.
 
diff --git a/src/common.h b/src/common.h
index b644b5f..30c7686 100644
--- a/src/common.h
+++ b/src/common.h
@@ -1,3 +1,20 @@
+/*  
+ * ZRE - A lightweight, portable programming language for permacomputing.  
+ * Copyright (C) 2025 zongor
+ *  
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, either version 3 of the License, or  
+ * (at your option) any later version.  
+ *  
+ * This program is distributed in the hope that it will be useful,  
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of  
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  
+ * GNU General Public License for more details.  
+ *  
+ * You should have received a copy of the GNU General Public License  
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.  
+ */  
 #ifndef ZRE_COMMON_H
 #define ZRE_COMMON_H
 
diff --git a/src/debug.c b/src/debug.c
index 0c6010c..7924fc1 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -1,3 +1,20 @@
+/*  
+ * ZRE - A lightweight, portable programming language for permacomputing.  
+ * Copyright (C) 2025 zongor
+ *  
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, either version 3 of the License, or  
+ * (at your option) any later version.  
+ *  
+ * This program is distributed in the hope that it will be useful,  
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of  
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  
+ * GNU General Public License for more details.  
+ *  
+ * You should have received a copy of the GNU General Public License  
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.  
+ */  
 #include "debug.h"
 
 int core_dump(Word *memory, uint32_t memory_size) {
diff --git a/src/debug.h b/src/debug.h
index d33a20c..ef3ccbc 100644
--- a/src/debug.h
+++ b/src/debug.h
@@ -1,3 +1,20 @@
+/*  
+ * ZRE - A lightweight, portable programming language for permacomputing.  
+ * Copyright (C) 2025 zongor
+ *  
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, either version 3 of the License, or  
+ * (at your option) any later version.  
+ *  
+ * This program is distributed in the hope that it will be useful,  
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of  
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  
+ * GNU General Public License for more details.  
+ *  
+ * You should have received a copy of the GNU General Public License  
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.  
+ */  
 #ifndef ZRE_DEBUG_H
 #define ZRE_DEBUG_H
 
diff --git a/src/main.c b/src/main.c
index 677a208..aec51aa 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,3 +1,20 @@
+/*  
+ * ZRE - A lightweight, portable programming language for permacomputing.  
+ * Copyright (C) 2025 zongor
+ *  
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, either version 3 of the License, or  
+ * (at your option) any later version.  
+ *  
+ * This program is distributed in the hope that it will be useful,  
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of  
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  
+ * GNU General Public License for more details.  
+ *  
+ * You should have received a copy of the GNU General Public License  
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.  
+ */  
 #include "debug.h"
 #include "vm.h"
 #ifdef __EMSCRIPTEN__
diff --git a/src/vm.c b/src/vm.c
index a40eb3e..a237996 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -1,3 +1,20 @@
+/*  
+ * ZRE - A lightweight, portable programming language for permacomputing.  
+ * Copyright (C) 2025 zongor
+ *  
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, either version 3 of the License, or  
+ * (at your option) any later version.  
+ *  
+ * This program is distributed in the hope that it will be useful,  
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of  
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  
+ * GNU General Public License for more details.  
+ *  
+ * You should have received a copy of the GNU General Public License  
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.  
+ */  
 #include "vm.h"
 
 #define MAX_LEN_INT32 11
diff --git a/src/vm.h b/src/vm.h
index 6e6a852..2f3f6f0 100644
--- a/src/vm.h
+++ b/src/vm.h
@@ -1,3 +1,20 @@
+/*  
+ * ZRE - A lightweight, portable programming language for permacomputing.  
+ * Copyright (C) 2025 zongor
+ *  
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, either version 3 of the License, or  
+ * (at your option) any later version.  
+ *  
+ * This program is distributed in the hope that it will be useful,  
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of  
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  
+ * GNU General Public License for more details.  
+ *  
+ * You should have received a copy of the GNU General Public License  
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.  
+ */  
 #ifndef ZRE_VM_H
 #define ZRE_VM_H