There is already a "fish" shell.
diff -ur bsd-games-2.17.orig/fish/Makefrag bsd-games-2.17/fish/Makefrag
--- bsd-games-2.17.orig/fish/Makefrag	1970-01-01 07:00:01.000000000 +0700
+++ bsd-games-2.17/fish/Makefrag	2020-08-06 19:18:43.204492847 +0700
@@ -31,7 +31,7 @@
 fish_all:	fish/fish fish/fish.instr fish/fish.6

 fish_install:	fish_all
-	$(INSTALL_BINARY) fish/fish $(INSTALL_PREFIX)$(GAMESDIR)/fish
+	$(INSTALL_BINARY) fish/fish $(INSTALL_PREFIX)$(GAMESDIR)/fish-game
	$(HIDE_GAME) fish
	$(INSTALL_DATA) fish/fish.instr $(INSTALL_PREFIX)$(FISH_INSTRFILE)
	$(INSTALL_MANUAL) fish/fish.6
'>
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<tr><td><span title='2020-12-13 00:35:49 +0100'>2020-12-13</span></td><td><a href='/guix/commit/gnu/services/security-token.scm?id=a4cd86ff4b7a9dd4bf1a5320b8121b470e381b67'>gnu: htop: Update to 3.0.3.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/admin.scm (htop): Update to 3.0.3.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-12-12 23:10:05 +0100'>2020-12-12</span></td><td><a href='/guix/commit/gnu/services/security-token.scm?id=8f2656f1debffe92ea088f4c88cfe8ec560b2ba3'>services: pcscd-shepherd-service: Fix PID file location.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;http://issues.guix.gnu.org/45202&gt;.

* gnu/services/security-token.scm (pcscd-shepherd-service): Look for
pcscd.pid in /run instead of /var/run.

Reported by Raffael Stocker &lt;r.stocker@mnet-mail.de&gt;.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>