docs: migrate to codeberg

wiki and release migration are TODO

 CONTRIBUTING.md           | 11 ++++++-----
 README.md                 |  8 +++++++-
 build.zig                 |  2 +-
 completions/zsh/_riverctl |  2 +-
 doc/river.1.scd           |  4 ++--
 doc/riverctl.1.scd        |  4 ++--
 doc/rivertile.1.scd       |  4 ++--
 7 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 3dc8b75..1c5d6d8 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -1,9 +1,10 @@
 ## Contributing to river
 
-Contributing is as simple as opening a pull request on github. You'll
-likely have more success with your contribution if you visit
-[#river](https://web.libera.chat/?channels=#river) on irc.libera.chat to
-discuss your plans first.
+Contributing is as simple as opening a pull request on
+[codeberg](https://codeberg.org/river/river).
+You'll likely have more success with your contribution if you visit
+[#river](https://web.libera.chat/?channels=#river) on irc.libera.chat to discuss
+your plans first.
 
 ## Commit messages
 
@@ -26,7 +27,7 @@ river-status: send view_tags on view map/unmap
 
 In addition to the summary, feel free to add any other details you want preceded
 by a blank line. A good rule of thumb is that anything you would write in a pull
-request description on github has a place in the commit message as well.
+request description on codeberg has a place in the commit message as well.
 
 For further details regarding commit style and git history see
 [weston's contributing guidelines](https://gitlab.freedesktop.org/wayland/weston/-/blob/master/CONTRIBUTING.md#formatting-and-separating-commits).
diff --git a/README.md b/README.md
index 0cb671f..b62e9c5 100644
--- a/README.md
+++ b/README.md
@@ -7,10 +7,16 @@ Install from your [package manager](https://repology.org/project/river/versions)
 Join us at [#river](https://web.libera.chat/?channels=#river) on irc.libera.chat —
 Read our man pages and [wiki](https://github.com/riverwm/river/wiki)
 
+The main repository is on [codeberg](https://codeberg.org/river/river),
+which is where the issue tracker may be found and where contributions are accepted.
+
+Read-only mirrors exist on [sourcehut](https://git.sr.ht/~ifreund/river)
+and [github](https://github.com/riverwm/river).
+
 *Note: river is currently early in development. Expect breaking
 changes and missing features. Bugs should however be rare at
 this point, if you run into one don't hesitate to [open an
-issue](https://github.com/riverwm/river/issues/new)*
+issue](https://codeberg.org/river/river/issues/new)*
 
 ## Design goals
 
diff --git a/build.zig b/build.zig
index 3361d06..a0995b6 100644
--- a/build.zig
+++ b/build.zig
@@ -246,7 +246,7 @@ pub fn build(b: *Build) !void {
             \\pkgdatadir=${{datadir}}/river-protocols
             \\
             \\Name: river-protocols
-            \\URL: https://github.com/riverwm/river
+            \\URL: https://codeberg.org/river/river
             \\Description: protocol files for the river wayland compositor
             \\Version: {s}
         , .{ b.install_prefix, full_version }));
diff --git a/completions/zsh/_riverctl b/completions/zsh/_riverctl
index a4c17fa..f3a655e 100644
--- a/completions/zsh/_riverctl
+++ b/completions/zsh/_riverctl
@@ -1,6 +1,6 @@
 #compdef riverctl
 #
-# Completion script for riverctl, part of river <https://github.com/riverwm/river>
+# Completion script for riverctl, part of river <https://codeberg.org/river/river>
 
 # This is the list of all riverctl first argument, i.e `riverctl <first_arg>`.
 # If a command doesn't need completion for subcommands then you just need
diff --git a/doc/river.1.scd b/doc/river.1.scd
index 304be55..9ac29d8 100644
--- a/doc/river.1.scd
+++ b/doc/river.1.scd
@@ -1,4 +1,4 @@
-RIVER(1) "github.com/riverwm/river" "General Commands Manual"
+RIVER(1) "codeberg.org/river/river" "General Commands Manual"
 
 # NAME
 
@@ -57,7 +57,7 @@ perform other configuration.
 
 Maintained by Isaac Freund <[email protected]> who is assisted by open
 source contributors. For more information about river's development, see
-<https://github.com/riverwm/river>.
+<https://codeberg.org/river/river>.
 
 # SEE ALSO
 
diff --git a/doc/riverctl.1.scd b/doc/riverctl.1.scd
index cbcac17..3c6175e 100644
--- a/doc/riverctl.1.scd
+++ b/doc/riverctl.1.scd
@@ -1,4 +1,4 @@
-RIVERCTL(1) "github.com/riverwm/river" "General Commands Manual"
+RIVERCTL(1) "codeberg.org/river/river" "General Commands Manual"
 
 # NAME
 
@@ -550,7 +550,7 @@ Bind Super+Shift+J to swap the focused view with the next visible view:
 
 Maintained by Isaac Freund <[email protected]> who is assisted by open
 source contributors. For more information about river's development, see
-<https://github.com/riverwm/river>.
+<https://codeberg.org/river/river>.
 
 # SEE ALSO
 
diff --git a/doc/rivertile.1.scd b/doc/rivertile.1.scd
index a91994b..b71b1d4 100644
--- a/doc/rivertile.1.scd
+++ b/doc/rivertile.1.scd
@@ -1,4 +1,4 @@
-RIVERTILE(1) "github.com/riverwm/river" "General Commands Manual"
+RIVERTILE(1) "codeberg.org/river/river" "General Commands Manual"
 
 # NAME
 
@@ -81,7 +81,7 @@ Set the main count to 3 at runtime:
 
 Maintained by Isaac Freund <[email protected]> who is assisted by open
 source contributors. For more information about river's development, see
-<https://github.com/riverwm/river>.
+<https://codeberg.org/river/river>.
 
 # SEE ALSO