diff --git a/doc/guix.texi b/doc/guix.texi
index c2da4ce17305dac0f67176ff852200647b1e2415..96448c24e51b4a69594db7af6bfa7bd7d89d2387 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -8048,7 +8048,7 @@ guix build --with-branch=guile-sqlite3=master cuirass
 @item --with-commit=@var{package}=@var{commit}
 This is similar to @code{--with-branch}, except that it builds from
 @var{commit} rather than the tip of a branch.  @var{commit} must be a valid
-Git commit SHA1 identifier.
+Git commit SHA1 identifier or a tag.
 @end table
 
 @node Additional Build Options
diff --git a/guix/git.scm b/guix/git.scm
index fb2df2de0782ea05c430985b4641c804802cfdb7..85252629fcb839f899be30d69e5982d2c09757bf 100644
--- a/guix/git.scm
+++ b/guix/git.scm
@@ -330,7 +330,7 @@ (define-record-type* <git-checkout>
   git-checkout?
   (url     git-checkout-url)
   (branch  git-checkout-branch (default "master"))
-  (commit  git-checkout-commit (default #f))
+  (commit  git-checkout-commit (default #f))      ;#f | tag | commit
   (recursive? git-checkout-recursive? (default #f)))
 
 (define* (latest-repository-commit* url #:key ref recursive? log-port)
@@ -369,7 +369,7 @@ (define-gexp-compiler (git-checkout-compiler (checkout <git-checkout>)
     (($ <git-checkout> url branch commit recursive?)
      (latest-repository-commit* url
                                 #:ref (if commit
-                                          `(commit . ,commit)
+                                          `(tag-or-commit . ,commit)
                                           `(branch . ,branch))
                                 #:recursive? recursive?
                                 #:log-port (current-error-port)))))
diff --git a/tests/guix-build-branch.sh b/tests/guix-build-branch.sh
index e64782c831a9f041ede047155108c012941cf74f..0cec7c75dbaf7e96aaf5441806cbca6a98380a82 100644
--- a/tests/guix-build-branch.sh
+++ b/tests/guix-build-branch.sh
@@ -1,5 +1,5 @@
 # GNU Guix --- Functional package management for GNU
-# Copyright © 2018 Ludovic Courtès <ludo@gnu.org>
+# Copyright © 2018, 2019 Ludovic Courtès <ludo@gnu.org>
 #
 # This file is part of GNU Guix.
 #
@@ -52,5 +52,11 @@ guix gc -R "$v0_1_0_drv" | grep guile-gcrypt-git.9e3eacd
 test "$v0_1_0_drv" != "$latest_drv"
 test "$v0_1_0_drv" != "$orig_drv"
 
+v0_1_0_drv="`guix build guix --with-commit=guile-gcrypt=v0.1.0 -d`"
+guix gc -R "$v0_1_0_drv" | grep guile-gcrypt-git.v0.1.0
+guix gc -R "$v0_1_0_drv" | grep guile-gcrypt-8fe64e8 # this is the *tag* ID
+test "$v0_1_0_drv" != "$latest_drv"
+test "$v0_1_0_drv" != "$orig_drv"
+
 if guix build guix --with-commit=guile-gcrypt=000 -d
 then false; else true; fi