remove -j4 since it doesn't have significant improvements
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3ca7dd4..65c1e95 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -72,5 +72,5 @@
         mkdir -p build
         cd build
         cmake .. -DOPENSSL_ROOT_DIR="$(brew --prefix ${OPENSSL})"
-        make -j4 all VERBOSE=1
+        make all VERBOSE=1
         make check
diff --git a/misc/docker-ci.mk b/misc/docker-ci.mk
index aa872cf..9c543f0 100644
--- a/misc/docker-ci.mk
+++ b/misc/docker-ci.mk
@@ -19,5 +19,5 @@
 
 _do-check:
 	cmake $(CMAKE_ARGS) "-H$(SRC_DIR)" -B.
-	komake -j4 all VERBOSE=1
+	make all VERBOSE=1
 	env $(CHECK_ENVS) make check