diff --git a/include/ureact/adaptor/join.hpp b/include/ureact/adaptor/join.hpp
index bbf0985..539f4c4 100644
--- a/include/ureact/adaptor/join.hpp
+++ b/include/ureact/adaptor/join.hpp
@@ -36,59 +36,10 @@ struct JoinClosure : AdaptorClosure
     }
 };
 
-struct JoinWithAdaptor : Adaptor
-{
-    /*!
-	 * @brief Emits the sequence obtained from flattening received event value, with the delimiter in between elements
-     * 
-     * The delimiter can be a single element or an iterable container of elements.
-	 */
-    template <typename InE, typename Pattern>
-    UREACT_WARN_UNUSED_RESULT constexpr auto operator()(
-        const events<InE>& source, Pattern&& pattern ) const
-    {
-        using E = container_value_t<InE>;
-        return process<E>( source,                                     //
-            [first = true, pattern = std::forward<Pattern>( pattern )] //
-            ( event_range<InE> range, event_emitter<E> out ) mutable {
-                if( !first )
-                {
-                    if constexpr( std::is_convertible_v<decltype( pattern ), E> )
-                    {
-                        out << pattern;
-                    }
-                    else if constexpr( std::is_convertible_v<container_value_t<decltype( pattern )>,
-                                           E> )
-                    {
-                        for( const auto& i : pattern )
-                            out << i;
-                    }
-                    else
-                    {
-                        static_assert( always_false<Pattern>, "Unsupported separator type" );
-                    }
-                }
-                first = false;
-
-                for( const auto& e : range )
-                    for( const auto& i : e )
-                        out << i;
-            } );
-    }
-
-    template <typename Pattern>
-    UREACT_WARN_UNUSED_RESULT constexpr auto operator()( Pattern&& pattern ) const
-    {
-        return make_partial<JoinWithAdaptor>( std::forward<Pattern>( pattern ) );
-    }
-};
-
 } // namespace detail
 
 inline constexpr detail::JoinClosure join;
 
-inline constexpr detail::JoinWithAdaptor join_with;
-
 UREACT_END_NAMESPACE
 
 #endif // UREACT_ADAPTOR_JOIN_HPP
diff --git a/include/ureact/adaptor/join_with.hpp b/include/ureact/adaptor/join_with.hpp
new file mode 100644
index 0000000..9859a4d
--- /dev/null
+++ b/include/ureact/adaptor/join_with.hpp
@@ -0,0 +1,74 @@
+//
+//         Copyright (C) 2014-2017 Sebastian Jeckel.
+//         Copyright (C) 2020-2023 Krylov Yaroslav.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef UREACT_ADAPTOR_JOIN_WITH_HPP
+#define UREACT_ADAPTOR_JOIN_WITH_HPP
+
+#include <ureact/adaptor/process.hpp>
+#include <ureact/detail/container_type_traits.hpp>
+
+UREACT_BEGIN_NAMESPACE
+
+namespace detail
+{
+
+struct JoinWithAdaptor : Adaptor
+{
+    /*!
+	 * @brief Emits the sequence obtained from flattening received event value, with the delimiter in between elements
+     * 
+     * The delimiter can be a single element or an iterable container of elements.
+	 */
+    template <typename InE, typename Pattern>
+    UREACT_WARN_UNUSED_RESULT constexpr auto operator()(
+        const events<InE>& source, Pattern&& pattern ) const
+    {
+        using E = container_value_t<InE>;
+        return process<E>( source,                                     //
+            [first = true, pattern = std::forward<Pattern>( pattern )] //
+            ( event_range<InE> range, event_emitter<E> out ) mutable {
+                if( !first )
+                {
+                    if constexpr( std::is_convertible_v<decltype( pattern ), E> )
+                    {
+                        out << pattern;
+                    }
+                    else if constexpr( std::is_convertible_v<container_value_t<decltype( pattern )>,
+                                           E> )
+                    {
+                        for( const auto& i : pattern )
+                            out << i;
+                    }
+                    else
+                    {
+                        static_assert( always_false<Pattern>, "Unsupported separator type" );
+                    }
+                }
+                first = false;
+
+                for( const auto& e : range )
+                    for( const auto& i : e )
+                        out << i;
+            } );
+    }
+
+    template <typename Pattern>
+    UREACT_WARN_UNUSED_RESULT constexpr auto operator()( Pattern&& pattern ) const
+    {
+        return make_partial<JoinWithAdaptor>( std::forward<Pattern>( pattern ) );
+    }
+};
+
+} // namespace detail
+
+inline constexpr detail::JoinWithAdaptor join_with;
+
+UREACT_END_NAMESPACE
+
+#endif // UREACT_ADAPTOR_JOIN_WITH_HPP
diff --git a/tests/src/CMakeLists.txt b/tests/src/CMakeLists.txt
index bd24b59..dffcd97 100644
--- a/tests/src/CMakeLists.txt
+++ b/tests/src/CMakeLists.txt
@@ -24,6 +24,7 @@ target_sources(
         adaptor/happened.cpp
         adaptor/hold.cpp
         adaptor/join.cpp
+        adaptor/join_with.cpp
         adaptor/keys.cpp
         adaptor/lift.cpp
         adaptor/merge.cpp
diff --git a/tests/src/adaptor/join.cpp b/tests/src/adaptor/join.cpp
index 5f43a42..c3127cd 100644
--- a/tests/src/adaptor/join.cpp
+++ b/tests/src/adaptor/join.cpp
@@ -79,36 +79,3 @@ TEST_CASE( "ureact::join (bits)" )
 
     CHECK( result.get() == std::vector<bool>{ /*0b*/ 1, 0, 1, 0, /*'*/ 1, 0, 1, 1 } );
 }
-
-// Based on https://en.cppreference.com/w/cpp/ranges/join_with_view
-TEST_CASE( "ureact::join_with" )
-{
-    ureact::context ctx;
-
-    auto src = ureact::make_source<std::string_view>( ctx );
-    ureact::events<char> chars_1;
-    ureact::events<char> chars_2;
-
-    using namespace std::literals;
-
-    SECTION( "Functional syntax" )
-    {
-        chars_1 = ureact::join_with( src, ' ' );
-        chars_2 = ureact::join_with( src, ".."sv );
-    }
-    SECTION( "Piped syntax" )
-    {
-        chars_1 = src | ureact::join_with( ' ' );
-        chars_2 = src | ureact::join_with( ".."sv );
-    }
-
-    const auto result_1 = ureact::collect<std::basic_string>( chars_1 );
-    const auto result_2 = ureact::collect<std::basic_string>( chars_2 );
-
-    using namespace std::literals;
-    for( auto s : { "This"sv, "is"sv, "a"sv, "test."sv } )
-        src << s;
-
-    CHECK( result_1.get() == "This is a test."s );
-    CHECK( result_2.get() == "This..is..a..test."s );
-}
diff --git a/tests/src/adaptor/join_with.cpp b/tests/src/adaptor/join_with.cpp
new file mode 100644
index 0000000..d34e4e1
--- /dev/null
+++ b/tests/src/adaptor/join_with.cpp
@@ -0,0 +1,48 @@
+//
+//         Copyright (C) 2020-2023 Krylov Yaroslav.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+//
+#include "ureact/adaptor/join_with.hpp"
+
+#include <string>
+#include <string_view>
+
+#include "catch2_extra.hpp"
+#include "ureact/adaptor/collect.hpp"
+#include "ureact/events.hpp"
+
+// Based on https://en.cppreference.com/w/cpp/ranges/join_with_view
+TEST_CASE( "ureact::join_with" )
+{
+    ureact::context ctx;
+
+    auto src = ureact::make_source<std::string_view>( ctx );
+    ureact::events<char> chars_1;
+    ureact::events<char> chars_2;
+
+    using namespace std::literals;
+
+    SECTION( "Functional syntax" )
+    {
+        chars_1 = ureact::join_with( src, ' ' );
+        chars_2 = ureact::join_with( src, ".."sv );
+    }
+    SECTION( "Piped syntax" )
+    {
+        chars_1 = src | ureact::join_with( ' ' );
+        chars_2 = src | ureact::join_with( ".."sv );
+    }
+
+    const auto result_1 = ureact::collect<std::basic_string>( chars_1 );
+    const auto result_2 = ureact::collect<std::basic_string>( chars_2 );
+
+    using namespace std::literals;
+    for( auto s : { "This"sv, "is"sv, "a"sv, "test."sv } )
+        src << s;
+
+    CHECK( result_1.get() == "This is a test."s );
+    CHECK( result_2.get() == "This..is..a..test."s );
+}