diff --git a/ci/aarch64-openbsd-debug.sh b/ci/aarch64-openbsd-debug.sh
index 70efda05a9e70693b773250da8fa1e78d199281c..fa8641836a317d305bbf45eca76a390073db368a 100755
--- a/ci/aarch64-openbsd-debug.sh
+++ b/ci/aarch64-openbsd-debug.sh
@@ -50,6 +50,7 @@ stage3-debug/bin/zig build install test docs \
   -Duse-zig-libcxx \
   -Denable-llvm \
   -Dno-lib \
-  -Dskip-non-native
+  -Dskip-non-native \
+  -Dskip-single-threaded
 
 stage4-debug/bin/zig test ../test/behavior.zig
diff --git a/ci/aarch64-openbsd-release.sh b/ci/aarch64-openbsd-release.sh
index e194f6ecb1b9a244a3171c1297b94b7e9b26f70d..fe5c586f58848708280a983306ce0774da4dfd0e 100755
--- a/ci/aarch64-openbsd-release.sh
+++ b/ci/aarch64-openbsd-release.sh
@@ -52,7 +52,8 @@ stage3-release/bin/zig build install test docs \
   -Duse-zig-libcxx \
   -Denable-llvm \
   -Dno-lib \
-  -Dskip-non-native
+  -Dskip-non-native \
+  -Dskip-single-threaded
 
 # Ensure that the fuzzer at least compiles.
 # https://codeberg.org/ziglang/zig/issues/30728
diff --git a/ci/riscv64-linux-debug.sh b/ci/riscv64-linux-debug.sh
index da378243787f312266399bc414b0e12fefae8b71..70f493bc85206aaf0c229110edf123f0a4fead1f 100755
--- a/ci/riscv64-linux-debug.sh
+++ b/ci/riscv64-linux-debug.sh
@@ -50,6 +50,7 @@ stage3-debug/bin/zig build install test docs \
   -Duse-zig-libcxx \
   -Denable-llvm \
   -Dno-lib \
-  -Dskip-non-native
+  -Dskip-non-native \
+  -Dskip-single-threaded
 
 stage4-debug/bin/zig test ../test/behavior.zig
diff --git a/ci/riscv64-linux-release.sh b/ci/riscv64-linux-release.sh
index 89d42ec283a84065bd51a2f99e63efd601b4423a..92534f6cfeed0fc7064e22ecd102aabce17464fe 100755
--- a/ci/riscv64-linux-release.sh
+++ b/ci/riscv64-linux-release.sh
@@ -52,7 +52,8 @@ stage3-release/bin/zig build install test docs \
   -Duse-zig-libcxx \
   -Denable-llvm \
   -Dno-lib \
-  -Dskip-non-native
+  -Dskip-non-native \
+  -Dskip-single-threaded
 
 # Ensure that the fuzzer at least compiles.
 stage3-release/bin/zig build test-std --fuzz=1K -Dno-lib -Dfuzz-only -Doptimize=ReleaseSafe