diff --git a/internal/sys.cpp b/internal/sys.cpp
index c87d5e6..7e765a9 100644
--- a/internal/sys.cpp
+++ b/internal/sys.cpp
@@ -21,10 +21,6 @@
 #include <sys/mman.h>
 #include <unistd.h>
 
-namespace blobs
-{
-namespace flash
-{
 namespace internal
 {
 
@@ -62,5 +58,3 @@
 SysImpl sys_impl;
 
 } // namespace internal
-} // namespace flash
-} // namespace blobs
diff --git a/internal/sys.hpp b/internal/sys.hpp
index 9327799..c013d3d 100644
--- a/internal/sys.hpp
+++ b/internal/sys.hpp
@@ -12,10 +12,6 @@
 #include <cinttypes>
 #include <cstddef>
 
-namespace blobs
-{
-namespace flash
-{
 namespace internal
 {
 
@@ -58,5 +54,3 @@
 extern SysImpl sys_impl;
 
 } // namespace internal
-} // namespace flash
-} // namespace blobs
diff --git a/lpc_aspeed.hpp b/lpc_aspeed.hpp
index 47c7a4a..1c4481a 100644
--- a/lpc_aspeed.hpp
+++ b/lpc_aspeed.hpp
@@ -14,8 +14,8 @@
     static std::unique_ptr<LpcMapperInterface>
         createAspeedMapper(size_t regionSize);
 
-    LpcMapperAspeed(size_t regionSize, const flash::internal::Sys* sys =
-                                           &flash::internal::sys_impl) :
+    LpcMapperAspeed(size_t regionSize,
+                    const internal::Sys* sys = &internal::sys_impl) :
         regionSize(regionSize),
         sys(sys){};
 
@@ -24,7 +24,7 @@
 
   private:
     size_t regionSize;
-    const flash::internal::Sys* sys;
+    const internal::Sys* sys;
 };
 
 } // namespace blobs
diff --git a/lpc_nuvoton.hpp b/lpc_nuvoton.hpp
index 0bb25af..61cc806 100644
--- a/lpc_nuvoton.hpp
+++ b/lpc_nuvoton.hpp
@@ -19,15 +19,14 @@
      * @param[in] a sys call interface pointer.
      * @todo Needs reserved memory region's physical address and size.
      */
-    explicit LpcMapperNuvoton(
-        const flash::internal::Sys* sys = &flash::internal::sys_impl) :
+    explicit LpcMapperNuvoton(const internal::Sys* sys = &internal::sys_impl) :
         sys(sys){};
 
     std::pair<std::uint32_t, std::uint32_t>
         mapWindow(std::uint32_t address, std::uint32_t length) override;
 
   private:
-    const flash::internal::Sys* sys;
+    const internal::Sys* sys;
 };
 
 } // namespace blobs
diff --git a/test/internal_sys_mock.hpp b/test/internal_sys_mock.hpp
index 1171540..2210d6f 100644
--- a/test/internal_sys_mock.hpp
+++ b/test/internal_sys_mock.hpp
@@ -6,10 +6,6 @@
 
 #include <gmock/gmock.h>
 
-namespace blobs
-{
-namespace flash
-{
 namespace internal
 {
 
@@ -27,5 +23,3 @@
 };
 
 } // namespace internal
-} // namespace flash
-} // namespace blobs