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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<div class='path'>path: <a href='/guix/log/?id=041a12c46b77094c3a89276cf55d9cf1f68fb9a3&amp;showmsg=1'>root</a>/<a href='/guix/log/gnu?id=041a12c46b77094c3a89276cf55d9cf1f68fb9a3&amp;showmsg=1'>gnu</a>/<a href='/guix/log/gnu/packages?id=041a12c46b77094c3a89276cf55d9cf1f68fb9a3&amp;showmsg=1'>packages</a>/<a href='/guix/log/gnu/packages/usb-modeswitch.scm?id=041a12c46b77094c3a89276cf55d9cf1f68fb9a3&amp;showmsg=1'>usb-modeswitch.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/usb-modeswitch.scm?id=041a12c46b77094c3a89276cf55d9cf1f68fb9a3'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2020-07-14 03:25:04 +0200'>2020-07-14</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/usb-modeswitch.scm?id=9cb208d86b0fae4b5c2b9ef4fa38a43594434c78'>gnu: usb-modeswitch: Use CC-FOR-TARGET.</a></td><td>Tobias Geerinckx-Rice</td></tr>
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* gnu/packages/usb-modeswitch.scm (usb-modeswitch)[arguments]: Use
CC-FOR-TARGET.


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<tr class='logheader'><td><span title='2020-07-14 03:25:04 +0200'>2020-07-14</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/usb-modeswitch.scm?id=dbfd8044254f794c7ee56ae275522674e180bc9c'>gnu: usb-modeswitch: Update to 2.6.1.</a></td><td>Tobias Geerinckx-Rice</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* gnu/packages/usb-modeswitch.scm (usb-modeswitch): Update to 2.6.1.


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