diff --git a/knots.scm b/knots.scm
index ed353f1..089f986 100644
--- a/knots.scm
+++ b/knots.scm
@@ -1,3 +1,22 @@
+;;; Guile Knots
+;;; Copyright © 2026 Christopher Baines <mail@cbaines.net>
+;;;
+;;; This file is part of Guile Knots.
+;;;
+;;; The Guile Knots 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.
+;;;
+;;; The Guile Knots 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 the guix-data-service.  If not, see
+;;; <http://www.gnu.org/licenses/>.
+
 (define-module (knots)
   #:use-module (srfi srfi-1)
   #:use-module (ice-9 match)