diff --git a/doc.go b/doc.go
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+// Package suika is a hard-fork of the 0.3 series of soju, an user-friendly IRC bouncer in Go.
+//
+// # Copyright (C) 2020 The soju Contributors
+// # Copyright (C) 2023-present Aoi Koizumi et al.
+//
+// suika is covered by the AGPLv3 license:
+//
+// 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/>.
+package suika