diff --git a/default.nix b/default.nix
index b8965954..0c8ba3a3 100644
--- a/default.nix
+++ b/default.nix
@@ -1,3 +1,23 @@
+# How to upgrade to a newer version
+# - Comment `src.hash`
+# - Change `version`
+# - Run `$ nix build`
+# This will fetch the source code
+# Since `hash` is not provided, nix will stop building and throw an error:
+#
+# error: hash mismatch in fixed-output derivation '/nix/store/fghi3ljs6fhz8pwm3dh73j5fwjpq5wbz-source.drv':
+#          specified: sha256-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=
+#             got:    sha256-+uthA1w8CmZfW+WOK9wYGl2fUl/k10ufOc8W+Pwa9iQ=
+# error: 1 dependencies of derivation '/nix/store/imcwsw5r74vkd8r0qa2k7cys2xfgraaz-tildefriends-0.0.18.drv' failed to build
+#
+# - Change `src.hash` to the new one, ie `sha256-+uthA1w8CmZfW+WOK9wYGl2fUl/k10ufOc8W+Pwa9iQ=`
+# - Uncomment `src.hash`
+# - Build again, this time it should work.
+# - Check the release notes, if there's a new dependency or a change to `GNUMakefile`, this file might need to be changed too.
+# For more details, contact tasiaiso @ https://tilde.club/~tasiaiso/
+#
+# WARNING: currently it is pinned to `47838d5e482cb4aac40190fa0414f08b8cf94d40`. I couldn't get v0.0.18 to work for some reason.
+# I'll change this in the next release - tasiaiso
 {
   pkgs ? import <nixpkgs> {},
   lib ? import <nixpkgs/lib>,