diff --git a/.builds/guix.yml b/.builds/guix.yml
index a4bc8b506dd61da69504c7992647db41eafb1ff0..b2d0e057a9a48527404e9119d4d3df43641dcaaa 100644
--- a/.builds/guix.yml
+++ b/.builds/guix.yml
@@ -22,7 +22,7 @@ tasks:
     [ "$BUILD_REASON" = patchset ] || rm -rf sgx-jmp
 - build: |
     if [ "$BUILD_REASON" = patchset ]; then with_source="--with-source=$PWD/sgx-jmp"; fi
-    guix build $with_source --no-grafts -r out -L. sgx-jmp
+    guix time-machine --commit=3455a004ec78a8c8a579b74da8039fbcd36cea73 -- guix build $with_source --no-grafts -r out -L. sgx-jmp
 - archive: |
     if [ -e signing-key.sec ]; then
       sudo mv signing-key.pub /etc/guix/
@@ -30,5 +30,5 @@ tasks:
       sudo chown root:root /etc/guix/signing-key.sec
       sudo chmod 0400 /etc/guix/signing-key.sec
     fi
-    guix archive --export -r --no-grafts $(readlink -f out) > sgx-jmp.nar
+    guix time-machine --commit=3455a004ec78a8c8a579b74da8039fbcd36cea73 -- guix archive --export -r --no-grafts $(readlink -f out) > sgx-jmp.nar
     plzip sgx-jmp.nar