diff --git a/kleidicv/include/kleidicv/kleidicv.h b/kleidicv/include/kleidicv/kleidicv.h
index 54d8cc4bcd4c31cb925fd93bd7964c4e7874e247..03836ff2e9132cd193a9a63abd0e19bb6f836cf6 100644
--- a/kleidicv/include/kleidicv/kleidicv.h
+++ b/kleidicv/include/kleidicv/kleidicv.h
@@ -1116,9 +1116,9 @@ KLEIDICV_API_DECLARATION(kleidicv_resize_linear_f32, const float *src,
 /// @param channels     Number of channels in the data. Must be not more than
 ///                     @ref KLEIDICV_MAXIMUM_CHANNEL_COUNT.
 ///
-KLEIDICV_API_DECLARATION(kleidicv_sobel_3x3_vertical_s16_u8, const uint8_t *src,
-                         size_t src_stride, int16_t *dst, size_t dst_stride,
-                         size_t width, size_t height, size_t channels);
+kleidicv_error_t kleidicv_sobel_3x3_vertical_s16_u8(
+    const uint8_t *src, size_t src_stride, int16_t *dst, size_t dst_stride,
+    size_t width, size_t height, size_t channels);
 
 /// Calculates horizontal derivative approximation with Sobel filter.
 ///
@@ -1154,10 +1154,9 @@ KLEIDICV_API_DECLARATION(kleidicv_sobel_3x3_vertical_s16_u8, const uint8_t *src,
 /// @param channels     Number of channels in the data. Must be not more than
 ///                     @ref KLEIDICV_MAXIMUM_CHANNEL_COUNT.
 ///
-KLEIDICV_API_DECLARATION(kleidicv_sobel_3x3_horizontal_s16_u8,
-                         const uint8_t *src, size_t src_stride, int16_t *dst,
-                         size_t dst_stride, size_t width, size_t height,
-                         size_t channels);
+kleidicv_error_t kleidicv_sobel_3x3_horizontal_s16_u8(
+    const uint8_t *src, size_t src_stride, int16_t *dst, size_t dst_stride,
+    size_t width, size_t height, size_t channels);
 
 #if KLEIDICV_EXPERIMENTAL_FEATURE_CANNY
 /// Canny edge detector for uint8_t grayscale input. Output is also a uint8_t
@@ -1267,13 +1266,11 @@ kleidicv_error_t kleidicv_filter_context_release(
 /// @param border_type   Way of handling the border.
 /// @param context       Pointer to filter context.
 ///
-KLEIDICV_API_DECLARATION(kleidicv_separable_filter_2d_u8, const uint8_t *src,
-                         size_t src_stride, uint8_t *dst, size_t dst_stride,
-                         size_t width, size_t height, size_t channels,
-                         const uint8_t *kernel_x, size_t kernel_width,
-                         const uint8_t *kernel_y, size_t kernel_height,
-                         kleidicv_border_type_t border_type,
-                         kleidicv_filter_context_t *context);
+kleidicv_error_t kleidicv_separable_filter_2d_u8(
+    const uint8_t *src, size_t src_stride, uint8_t *dst, size_t dst_stride,
+    size_t width, size_t height, size_t channels, const uint8_t *kernel_x,
+    size_t kernel_width, const uint8_t *kernel_y, size_t kernel_height,
+    kleidicv_border_type_t border_type, kleidicv_filter_context_t *context);
 
 /// Applies Gaussian blur to the source image using the specified parameters.
 /// In-place filtering is not supported.
@@ -1324,13 +1321,11 @@ KLEIDICV_API_DECLARATION(kleidicv_separable_filter_2d_u8, const uint8_t *src,
 /// @param border_type   Way of handling the border.
 /// @param context       Pointer to filter context.
 ///
-KLEIDICV_API_DECLARATION(kleidicv_gaussian_blur_u8, const uint8_t *src,
-                         size_t src_stride, uint8_t *dst, size_t dst_stride,
-                         size_t width, size_t height, size_t channels,
-                         size_t kernel_width, size_t kernel_height,
-                         float sigma_x, float sigma_y,
-                         kleidicv_border_type_t border_type,
-                         kleidicv_filter_context_t *context);
+kleidicv_error_t kleidicv_gaussian_blur_u8(
+    const uint8_t *src, size_t src_stride, uint8_t *dst, size_t dst_stride,
+    size_t width, size_t height, size_t channels, size_t kernel_width,
+    size_t kernel_height, float sigma_x, float sigma_y,
+    kleidicv_border_type_t border_type, kleidicv_filter_context_t *context);
 
 /// Splits a multi channel source stream into separate 1-channel streams. Width
 /// and height are the same for the source stream and for all the destination
diff --git a/kleidicv/src/filters/gaussian_blur_api.cpp b/kleidicv/src/filters/gaussian_blur_api.cpp
index 67d47d4fad5b873e88e4633052fe414be2366f50..bb21315ed6c061f50ff4a45273ad403873ed1dfe 100644
--- a/kleidicv/src/filters/gaussian_blur_api.cpp
+++ b/kleidicv/src/filters/gaussian_blur_api.cpp
@@ -11,8 +11,9 @@ KLEIDICV_MULTIVERSION_C_API(
     KLEIDICV_SVE2_IMPL_IF(kleidicv::sve2::gaussian_blur_stripe_u8),
     &kleidicv::sme2::gaussian_blur_stripe_u8);
 
-namespace kleidicv {
-static kleidicv_error_t gaussian_blur_u8(
+extern "C" {
+
+kleidicv_error_t kleidicv_gaussian_blur_u8(
     const uint8_t *src, size_t src_stride, uint8_t *dst, size_t dst_stride,
     size_t width, size_t height, size_t channels, size_t kernel_width,
     size_t kernel_height, float sigma_x, float sigma_y,
@@ -21,7 +22,5 @@ static kleidicv_error_t gaussian_blur_u8(
       src, src_stride, dst, dst_stride, width, height, 0, height, channels,
       kernel_width, kernel_height, sigma_x, sigma_y, border_type, context);
 }
-}  // namespace kleidicv
 
-KLEIDICV_MULTIVERSION_C_API(kleidicv_gaussian_blur_u8,
-                            &kleidicv::gaussian_blur_u8, nullptr, nullptr);
+}  // extern "C"
diff --git a/kleidicv/src/filters/separable_filter_2d_api.cpp b/kleidicv/src/filters/separable_filter_2d_api.cpp
index 028a66f01f9ee27e8ef228fe8c9e7c9bf23bc020..555b722af0761fe81d1556ff711489b3dd0cdd38 100644
--- a/kleidicv/src/filters/separable_filter_2d_api.cpp
+++ b/kleidicv/src/filters/separable_filter_2d_api.cpp
@@ -7,6 +7,12 @@
 #include "kleidicv/kleidicv.h"
 #include "kleidicv/workspace/separable.h"
 
+KLEIDICV_MULTIVERSION_C_API(
+    kleidicv_separable_filter_2d_stripe_u8,
+    &kleidicv::neon::separable_filter_2d_stripe_u8,
+    KLEIDICV_SVE2_IMPL_IF(kleidicv::sve2::separable_filter_2d_stripe_u8),
+    &kleidicv::sme2::separable_filter_2d_stripe_u8);
+
 extern "C" {
 
 using KLEIDICV_TARGET_NAMESPACE::Rectangle;
@@ -56,16 +62,7 @@ kleidicv_error_t kleidicv_filter_context_release(
   return KLEIDICV_OK;
 }
 
-}  // extern "C"
-
-KLEIDICV_MULTIVERSION_C_API(
-    kleidicv_separable_filter_2d_stripe_u8,
-    &kleidicv::neon::separable_filter_2d_stripe_u8,
-    KLEIDICV_SVE2_IMPL_IF(kleidicv::sve2::separable_filter_2d_stripe_u8),
-    &kleidicv::sme2::separable_filter_2d_stripe_u8);
-
-namespace kleidicv {
-static kleidicv_error_t separable_filter_2d_u8(
+kleidicv_error_t kleidicv_separable_filter_2d_u8(
     const uint8_t *src, size_t src_stride, uint8_t *dst, size_t dst_stride,
     size_t width, size_t height, size_t channels, const uint8_t *kernel_x,
     size_t kernel_width, const uint8_t *kernel_y, size_t kernel_height,
@@ -74,8 +71,5 @@ static kleidicv_error_t separable_filter_2d_u8(
       src, src_stride, dst, dst_stride, width, height, 0, height, channels,
       kernel_x, kernel_width, kernel_y, kernel_height, border_type, context);
 }
-}  // namespace kleidicv
 
-KLEIDICV_MULTIVERSION_C_API(kleidicv_separable_filter_2d_u8,
-                            &kleidicv::separable_filter_2d_u8, nullptr,
-                            nullptr);
+}  // extern "C"
diff --git a/kleidicv/src/filters/sobel_api.cpp b/kleidicv/src/filters/sobel_api.cpp
index 02f4724b01b56519ed0a92bb229345a4007b841c..ca0218e470b66c2a2c2fc4a51744f756ad9f90fa 100644
--- a/kleidicv/src/filters/sobel_api.cpp
+++ b/kleidicv/src/filters/sobel_api.cpp
@@ -17,24 +17,19 @@ KLEIDICV_DEFINE_C_API(kleidicv_sobel_3x3_horizontal_stripe_s16_u8,
 KLEIDICV_DEFINE_C_API(kleidicv_sobel_3x3_vertical_stripe_s16_u8,
                       sobel_3x3_vertical_stripe_s16_u8);
 
-namespace kleidicv {
-static kleidicv_error_t sobel_3x3_horizontal_s16_u8(
+extern "C" {
+
+kleidicv_error_t kleidicv_sobel_3x3_horizontal_s16_u8(
     const uint8_t *src, size_t src_stride, int16_t *dst, size_t dst_stride,
     size_t width, size_t height, size_t channels) {
   return kleidicv_sobel_3x3_horizontal_stripe_s16_u8(
       src, src_stride, dst, dst_stride, width, height, 0, height, channels);
 }
-static kleidicv_error_t sobel_3x3_vertical_s16_u8(
+kleidicv_error_t kleidicv_sobel_3x3_vertical_s16_u8(
     const uint8_t *src, size_t src_stride, int16_t *dst, size_t dst_stride,
     size_t width, size_t height, size_t channels) {
   return kleidicv_sobel_3x3_vertical_stripe_s16_u8(
       src, src_stride, dst, dst_stride, width, height, 0, height, channels);
 }
-}  // namespace kleidicv
 
-KLEIDICV_MULTIVERSION_C_API(kleidicv_sobel_3x3_horizontal_s16_u8,
-                            &kleidicv::sobel_3x3_horizontal_s16_u8, nullptr,
-                            nullptr);
-KLEIDICV_MULTIVERSION_C_API(kleidicv_sobel_3x3_vertical_s16_u8,
-                            &kleidicv::sobel_3x3_vertical_s16_u8, nullptr,
-                            nullptr);
+}  // extern "C"