diff --git a/docs/dev/clang-tidy-fixes-2026-04.md b/docs/dev/clang-tidy-fixes-2026-04.md
index a5d11079c..4722ed462 100644
--- a/docs/dev/clang-tidy-fixes-2026-04.md
+++ b/docs/dev/clang-tidy-fixes-2026-04.md
@@ -104,7 +104,8 @@
   - [PR #745](https://github.com/Framework-R-D/phlex/pull/745)
 - [x] [modernize-avoid-c-style-cast](https://clang.llvm.org/extra/clang-tidy/checks/modernize/avoid-c-style-cast.html) (82)
   - [PR #771](https://github.com/Framework-R-D/phlex/pull/771)
-- [ ] [modernize-concat-nested-namespaces](https://clang.llvm.org/extra/clang-tidy/checks/modernize/concat-nested-namespaces.html) (1)
+- [x] [modernize-concat-nested-namespaces](https://clang.llvm.org/extra/clang-tidy/checks/modernize/concat-nested-namespaces.html) (1)
+  - [PR #804](https://github.com/Framework-R-D/phlex/pull/804)
 - [x] [modernize-make-shared](https://clang.llvm.org/extra/clang-tidy/checks/modernize/make-shared.html) (1)
   - [PR #746](https://github.com/Framework-R-D/phlex/pull/746)
 - [x] [modernize-pass-by-value](https://clang.llvm.org/extra/clang-tidy/checks/modernize/pass-by-value.html) (13)
diff --git a/form/form/technology.hpp b/form/form/technology.hpp
index 01677eab8..1a95f8c83 100644
--- a/form/form/technology.hpp
+++ b/form/form/technology.hpp
@@ -1,27 +1,24 @@
 #ifndef FORM_FORM_TECHNOLOGY_HPP
 #define FORM_FORM_TECHNOLOGY_HPP
 
-namespace form {
-  namespace technology {
-    // Helper constants - make these constexpr too
-    constexpr int ROOT_MAJOR = 1;
-    constexpr int ROOT_TTREE_MINOR = 1;
-    constexpr int ROOT_RNTUPLE_MINOR = 2;
-    constexpr int HDF5_MAJOR = 2;
+namespace form::technology {
+  // Helper constants - make these constexpr too
+  constexpr int ROOT_MAJOR = 1;
+  constexpr int ROOT_TTREE_MINOR = 1;
+  constexpr int ROOT_RNTUPLE_MINOR = 2;
+  constexpr int HDF5_MAJOR = 2;
 
-    // Helper function for combining major/minor
-    constexpr int Combine(int major, int minor) { return (major * 256) + minor; }
+  // Helper function for combining major/minor
+  constexpr int Combine(int major, int minor) { return (major * 256) + minor; }
 
-    // Technology constants using the helper
-    constexpr int ROOT_TTREE = Combine(ROOT_MAJOR, ROOT_TTREE_MINOR);
-    constexpr int ROOT_RNTUPLE = Combine(ROOT_MAJOR, ROOT_RNTUPLE_MINOR);
-    constexpr int HDF5 = Combine(HDF5_MAJOR, 1);
+  // Technology constants using the helper
+  constexpr int ROOT_TTREE = Combine(ROOT_MAJOR, ROOT_TTREE_MINOR);
+  constexpr int ROOT_RNTUPLE = Combine(ROOT_MAJOR, ROOT_RNTUPLE_MINOR);
+  constexpr int HDF5 = Combine(HDF5_MAJOR, 1);
 
-    // Helper functions
-    inline int GetMajor(int tech) { return tech / 256; }
-    inline int GetMinor(int tech) { return tech % 256; }
-  }
-
-} // namespace form
+  // Helper functions
+  inline int GetMajor(int tech) { return tech / 256; }
+  inline int GetMinor(int tech) { return tech % 256; }
+} // namespace form::technology
 
 #endif // FORM_FORM_TECHNOLOGY_HPP