diff --git a/include/CMakeLists.txt b/include/CMakeLists.txt
index aca8685..987fe41 100644
--- a/include/CMakeLists.txt
+++ b/include/CMakeLists.txt
@@ -1,24 +1,36 @@
-# Library sources
-file(GLOB_RECURSE LIB_HDRS "${CMAKE_CURRENT_SOURCE_DIR}/matcher/*.hpp" "${CMAKE_CURRENT_SOURCE_DIR}/matcher/*.h")
-file(GLOB_RECURSE LIB_SRCS "${CMAKE_CURRENT_SOURCE_DIR}/matcher/impl/*.cpp")
+# Library headers
+# .hpp = public headers, .ipp = template implementation (included by .hpp)
+file(GLOB_RECURSE LIB_HDRS
+    "${CMAKE_CURRENT_SOURCE_DIR}/matcher/*.hpp"
+    "${CMAKE_CURRENT_SOURCE_DIR}/matcher/*.h"
+    "${CMAKE_CURRENT_SOURCE_DIR}/matcher/impl/*.ipp"
+)
 
 # Config header
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/RegexMatcherConfig.h.in ${CMAKE_CURRENT_SOURCE_DIR}/matcher/RegexMatcherConfig.h)
+configure_file(
+    ${CMAKE_CURRENT_SOURCE_DIR}/RegexMatcherConfig.h.in
+    ${CMAKE_CURRENT_SOURCE_DIR}/matcher/RegexMatcherConfig.h
+)
 
-# Core library
-add_library(RegexMatcher STATIC ${LIB_SRCS})
-target_sources(RegexMatcher PUBLIC FILE_SET regex_matcher_headers TYPE HEADERS FILES ${LIB_HDRS})
+# Header-only library (INTERFACE since all code is in headers/ipp files)
+add_library(RegexMatcher INTERFACE)
+target_sources(RegexMatcher INTERFACE FILE_SET regex_matcher_headers TYPE HEADERS FILES ${LIB_HDRS})
 target_include_directories(
     RegexMatcher
-    PUBLIC
+    INTERFACE
     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
     $<INSTALL_INTERFACE:include>
 )
-set_target_properties(RegexMatcher PROPERTIES LINKER_LANGUAGE CXX)
 
 # Set output properties
 set_target_properties(RegexMatcher PROPERTIES EXPORT_NAME core)
 
-install(FILES ${LIB_SRCS}
-    DESTINATION lib/RegexMatcher-${PROJECT_VERSION}/matcher/impl
+# Install headers
+install(
+    DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/matcher
+    DESTINATION include
+    FILES_MATCHING
+    PATTERN "*.hpp"
+    PATTERN "*.h"
+    PATTERN "*.ipp"
 )
diff --git a/include/matcher/core.hpp b/include/matcher/core.hpp
index b6ca72d..9eb7a6c 100644
--- a/include/matcher/core.hpp
+++ b/include/matcher/core.hpp
@@ -136,22 +136,6 @@ namespace {
 		}
 	};
 
-	/**
-	 * @brief Simulation state for tagged NFA traversal
-	 * Bundles all state needed during matching
-	 */
-	template <typename RegexData>
-	struct SimulationState {
-		std::vector<RegexData> active_paths;         // Currently active regex paths
-		std::map<RegexData, CaptureSlots> captures;  // Capture slots per regex
-
-		SimulationState() = default;
-		SimulationState(const SimulationState&) = default;
-		SimulationState& operator=(const SimulationState&) = default;
-		SimulationState(SimulationState&&) = default;
-		SimulationState& operator=(SimulationState&&) = default;
-	};
-
 	/**
 	 * @brief Class containing the list of regexes using the given edge
 	 *
@@ -473,8 +457,8 @@ namespace {
 	};
 }  // namespace
 
-#include <matcher/impl/subtree.cpp>
-#include <matcher/impl/node.cpp>
+#include <matcher/impl/subtree.ipp>
+#include <matcher/impl/node.ipp>
 
 namespace matcher {
 	template <typename RegexData, typename char_t>
@@ -538,4 +522,4 @@ namespace matcher {
 	};
 }  // namespace matcher
 
-#include <matcher/impl/core.cpp>
+#include <matcher/impl/core.ipp>
diff --git a/include/matcher/impl/core.cpp b/include/matcher/impl/core.ipp
similarity index 98%
rename from include/matcher/impl/core.cpp
rename to include/matcher/impl/core.ipp
index e93678c..d5e8f1a 100644
--- a/include/matcher/impl/core.cpp
+++ b/include/matcher/impl/core.ipp
@@ -1,7 +1,8 @@
-#ifndef CORE_IMPL
-#define CORE_IMPL
-
-#include <matcher/core.hpp>
+/**
+ * @file core.ipp
+ * @brief Template implementation for RegexMatcher class
+ * @note This file is included by core.hpp - do not include directly
+ */
 
 #include <list>
 
@@ -250,5 +251,3 @@ namespace matcher {
 	}
 
 }  // namespace matcher
-
-#endif
diff --git a/include/matcher/impl/node.cpp b/include/matcher/impl/node.ipp
similarity index 98%
rename from include/matcher/impl/node.cpp
rename to include/matcher/impl/node.ipp
index 5d64a48..cb2650b 100644
--- a/include/matcher/impl/node.cpp
+++ b/include/matcher/impl/node.ipp
@@ -1,7 +1,9 @@
-#ifndef NODE_IMPL
-#define NODE_IMPL
+/**
+ * @file node.ipp
+ * @brief Template implementation for Node class
+ * @note This file is included by core.hpp - do not include directly
+ */
 
-#include <matcher/core.hpp>
 #include <stack>
 
 namespace {
@@ -454,6 +456,4 @@ namespace {
 		print_helper(0, traversed, nodes);
 	}
 #endif
-}  // namespace
-
-#endif
+}  // anonymous namespace
diff --git a/include/matcher/impl/subtree.cpp b/include/matcher/impl/subtree.ipp
similarity index 59%
rename from include/matcher/impl/subtree.cpp
rename to include/matcher/impl/subtree.ipp
index 32897d5..b260e99 100644
--- a/include/matcher/impl/subtree.cpp
+++ b/include/matcher/impl/subtree.ipp
@@ -1,9 +1,11 @@
-#ifndef SUBTREE_IMPL
-#define SUBTREE_IMPL
-
-#include <matcher/core.hpp>
+/**
+ * @file subtree.ipp
+ * @brief Template implementation for SubTree class
+ * @note This file is included by core.hpp - do not include directly
+ */
 
 namespace {
+
 	template <typename Node_T>
 	inline const std::vector<Node_T*>& SubTree<Node_T>::get_roots() const {
 		return roots;
@@ -13,6 +15,5 @@ namespace {
 	inline const std::vector<Node_T*>& SubTree<Node_T>::get_leafs() const {
 		return leafs;
 	}
-}  // namespace
 
-#endif
+}  // anonymous namespace