diff --git a/include/merian/vk/shader/shader_module.hpp b/include/merian/vk/shader/shader_module.hpp
index 766af92..8a8a3d4 100644
--- a/include/merian/vk/shader/shader_module.hpp
+++ b/include/merian/vk/shader/shader_module.hpp
@@ -51,7 +51,7 @@ class ShaderModule : public std::enable_shared_from_this<ShaderModule> {
     operator ShaderStageCreateInfo();
 
     ShaderStageCreateInfo get_shader_stage_create_info(
-        const SpecializationInfoHandle specialization_info = MERIAN_SPECIALIZATION_INFO_NONE,
+        const SpecializationInfoHandle& specialization_info = MERIAN_SPECIALIZATION_INFO_NONE,
         const char* entry_point = "main",
         const vk::PipelineShaderStageCreateFlags flags = {});
 
@@ -72,7 +72,7 @@ class ShaderStageCreateInfo {
     ShaderStageCreateInfo(
         const ShaderModuleHandle& shader_module,
         const SpecializationInfoHandle& specialization_info = MERIAN_SPECIALIZATION_INFO_NONE,
-        const std::string entry_point = "main",
+        const std::string& entry_point = "main",
         const vk::PipelineShaderStageCreateFlags flags = {});
 
     operator vk::PipelineShaderStageCreateInfo() const;
diff --git a/src/merian/vk/shader/shader_module.cpp b/src/merian/vk/shader/shader_module.cpp
index f3b4446..73664b3 100644
--- a/src/merian/vk/shader/shader_module.cpp
+++ b/src/merian/vk/shader/shader_module.cpp
@@ -57,7 +57,7 @@ ShaderModule::operator ShaderStageCreateInfo() {
 }
 
 ShaderStageCreateInfo
-ShaderModule::get_shader_stage_create_info(const SpecializationInfoHandle specialization_info,
+ShaderModule::get_shader_stage_create_info(const SpecializationInfoHandle& specialization_info,
                                            const char* entry_point,
                                            const vk::PipelineShaderStageCreateFlags flags) {
     return ShaderStageCreateInfo(shared_from_this(), specialization_info, entry_point, flags);
@@ -71,7 +71,7 @@ ShaderModuleHandle ShaderModule::fullscreen_triangle(const ContextHandle& contex
 
 ShaderStageCreateInfo::ShaderStageCreateInfo(const ShaderModuleHandle& shader_module,
                                              const SpecializationInfoHandle& specialization_info,
-                                             const std::string entry_point,
+                                             const std::string& entry_point,
                                              const vk::PipelineShaderStageCreateFlags flags)
     : shader_module(shader_module), specialization_info(specialization_info),
       entry_point(entry_point), flags(flags) {}