diff --git a/mix.exs b/mix.exs
index caa86d395..489bb5729 100644
--- a/mix.exs
+++ b/mix.exs
@@ -229,7 +229,9 @@ defmodule Pleroma.Mixfile do
       "ecto.reset": ["ecto.drop", "ecto.setup"],
       test: ["ecto.create --quiet", "ecto.migrate", "test"],
       docs: ["pleroma.docs", "docs"],
-      analyze: ["credo --strict --only=warnings,todo,fixme,consistency,readability"]
+      analyze: ["credo --strict --only=warnings,todo,fixme,consistency,readability"],
+      copyright: &add_copyright/1,
+      "copyright.bump": &bump_copyright/1
     ]
   end
 
@@ -332,4 +334,30 @@ defmodule Pleroma.Mixfile do
     |> Enum.filter(fn string -> string && string != "" end)
     |> Enum.join()
   end
+
+  defp add_copyright(_) do
+    year = NaiveDateTime.utc_now().year
+    template = ~s[\
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-#{year} Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+] |> String.replace("\n", "\\n")
+
+    find = "find lib test priv -type f \\( -name '*.ex' -or -name '*.exs' \\) -exec "
+    grep = "grep -L '# Copyright © [0-9\-]* Pleroma' {} \\;"
+    xargs = "xargs -n1 sed -i'' '1s;^;#{template};'"
+
+    :os.cmd(String.to_charlist("#{find}#{grep} | #{xargs}"))
+  end
+
+  defp bump_copyright(_) do
+    year = NaiveDateTime.utc_now().year
+    find = "find lib test priv -type f \\( -name '*.ex' -or -name '*.exs' \\)"
+
+    xargs =
+      "xargs sed -i'' 's;# Copyright © [0-9\-]* Pleroma.*$;# Copyright © 2017-#{year} Pleroma Authors <https://pleroma.social/>;'"
+
+    :os.cmd(String.to_charlist("#{find} | #{xargs}"))
+  end
 end