diff --git a/ci.sh b/ci.sh
index 861e56f9..74125826 100755
--- a/ci.sh
+++ b/ci.sh
@@ -125,6 +125,16 @@ if true ; then
                     SKIP_SATYSFI_MISMATCH=1
             esac
 
+            case "$PACKAGE_NAME" in
+                satyrographos-snapshot-{develop,stable}.0.0.[345]+*)
+                    # https://github.com/na4zagin3/satyrographos/pull/289
+                    echo "Old Satyrographos sometimes fail with parallel build."
+                    export OPAMJOBS=1
+                    ;;
+                *)
+                    unset OPAMJOBS
+            esac
+
             if ! opam_install_dry_run --json=opam-output.json --cli=2.1 --update-invariant "${PACKAGES_AND_OPTIONS[@]}" "$SATYSFI_PACKAGE"
             then
                 echo "Dependency does not meet."