diff --git a/.gitignore b/.gitignore
index be56afb..983c6d4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,3 +13,4 @@ artifacts
 tmp
 package-lock.json
 /*.html
+/build
diff --git a/build-llvm.sh b/build-llvm.sh
index 96cf0a0..a2d9a68 100755
--- a/build-llvm.sh
+++ b/build-llvm.sh
@@ -13,11 +13,17 @@ fi
 
 
 # Build LLVM, clang
-cd llvm-project
+LLVM_SRC_PREFIX=${PWD}/llvm-project
+LLVM_SRC_DIR=${LLVM_SRC_PREFIX}/llvm
+LLVM_BUILD_DIR=${PWD}/build/llvm
+if [ ! -d ${LLVM_BUILD_DIR} ] ; then
+	mkdir -p ${LLVM_BUILD_DIR}
+fi
 
-mkdir -p build
-cd build
-cmake -G Ninja -DLLVM_ENABLE_ASSERTIONS=On \
+cmake -G Ninja \
+  -S ${LLVM_SRC_DIR} \
+  -B ${LLVM_BUILD_DIR} \
+  -DLLVM_ENABLE_ASSERTIONS=On \
   -DLLVM_ENABLE_TERMINFO=Off \
   -DLLVM_ENABLE_LIBXML2=Off \
   -DLLVM_ENABLE_ZLIB=Off \
@@ -25,17 +31,17 @@ cmake -G Ninja -DLLVM_ENABLE_ASSERTIONS=On \
   -DLLVM_TARGETS_TO_BUILD='RISCV' \
   -DLLVM_ENABLE_ZSTD=Off \
   -DCMAKE_BUILD_TYPE=MinSizeRel \
-  -DCMAKE_INSTALL_PREFIX=${INSTALL_DIR} \
-	../llvm
-
-ninja
-ninja install
+  -DCMAKE_INSTALL_PREFIX=${INSTALL_DIR}
 
+cmake --build ${LLVM_BUILD_DIR}
+cmake --install ${LLVM_BUILD_DIR}
 
 # Build compiler builtins
-cd ../compiler-rt
-mkdir -p build
-cd build
+COMPILER_RT_SRC_DIR=${LLVM_SRC_PREFIX}/compiler-rt
+COMPILER_RT_BUILD_DIR=${PWD}/build/compiler-rt
+if [ ! -d ${COMPILER_RT_BUILD_DIR} ] ; then
+	mkdir -p ${COMPILER_RT_BUILD_DIR}
+fi
 
 build_compiler_rt() {
 	case "$1" in
@@ -46,6 +52,8 @@ build_compiler_rt() {
 	CFLAGS="--target=riscv${1} -march=rv${1}em -mabi=${TARGET_ABI} -mcpu=generic-rv${1} -nostdlib -nodefaultlibs"
 
 	cmake -G Ninja \
+	  -S ${COMPILER_RT_SRC_DIR} \
+	  -B ${COMPILER_RT_BUILD_DIR} \
 	  -DCMAKE_BUILD_TYPE=Release \
 	  -DCMAKE_INSTALL_PREFIX=${INSTALL_DIR} \
 	  -DCOMPILER_RT_BUILD_BUILTINS=ON \
@@ -70,11 +78,10 @@ build_compiler_rt() {
 	  -DCOMPILER_RT_TEST_COMPILER=${INSTALL_DIR}/bin/clang \
 	  -DCMAKE_CXX_FLAGS="${CFLAGS}" \
 	  -DCMAKE_SYSTEM_NAME=unknown \
-	  -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON \
-	  ..
+	  -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON 
 	
-	ninja
-	ninja install
+	cmake --build ${COMPILER_RT_BUILD_DIR}
+	cmake --install ${COMPILER_RT_BUILD_DIR} 
 }
 
 build_compiler_rt 32