diff --git a/api.lua b/api.lua
index 8a1b551..9c82b5f 100644
--- a/api.lua
+++ b/api.lua
@@ -1,3 +1,18 @@
+-- Copyright (C) 2025  snoutie
+-- Authors: snoutie (copyright@achtarmig.org)
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU Affero 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 Affero General Public License for more details.
+
+-- You should have received a copy of the GNU Affero General Public License
+-- along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 --Stores liquid_id and the corresponding liquid node names
 liquid_physics.registered_liquids = {}
 
diff --git a/init.lua b/init.lua
index da1dea2..6759771 100644
--- a/init.lua
+++ b/init.lua
@@ -1,3 +1,18 @@
+-- Copyright (C) 2025  snoutie
+-- Authors: snoutie (copyright@achtarmig.org)
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU Affero 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 Affero General Public License for more details.
+
+-- You should have received a copy of the GNU Affero General Public License
+-- along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 local modpath = core.get_modpath(core.get_current_modname())
 
 liquid_physics = {}
diff --git a/physics.lua b/physics.lua
index 30a1620..d0a1174 100644
--- a/physics.lua
+++ b/physics.lua
@@ -1,3 +1,18 @@
+-- Copyright (C) 2025  snoutie
+-- Authors: snoutie (copyright@achtarmig.org)
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU Affero 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 Affero General Public License for more details.
+
+-- You should have received a copy of the GNU Affero General Public License
+-- along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 local offsets = {
     { x = 0,  z = 1, },
     { x = 0,  z = -1, },