diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 20d15d23..a1f57c7c 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -118,7 +118,6 @@ set(INTERNAL_HEADERS
     ${SOURCES_DIR}/catch_tostring.h
     ${SOURCES_DIR}/catch_totals.h
     ${SOURCES_DIR}/catch_uncaught_exceptions.h
-    ${SOURCES_DIR}/catch_user_interfaces.h
     ${SOURCES_DIR}/catch_version.h
     ${SOURCES_DIR}/catch_version_macros.hpp
     ${SOURCES_DIR}/catch_wildcard_pattern.h
diff --git a/src/catch2/catch_user_interfaces.h b/src/catch2/catch_user_interfaces.h
deleted file mode 100644
index 35acb77b..00000000
--- a/src/catch2/catch_user_interfaces.h
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- *  Created by Martin on 21/11/2017.
- *
- *  This file collects declaration that we want to expose to test files.
- *  These declarations are expected to be duplicated elsewhere,
- *  together with their implementation.
- *
- *  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 TWOBLUECUBES_CATCH_USER_INTERFACES_H_INCLUDED
-#define TWOBLUECUBES_CATCH_USER_INTERFACES_H_INCLUDED
-
-namespace Catch {
-    unsigned int rngSeed();
-}
-
-#endif // TWOBLUECUBES_CATCH_USER_INTERFACES_H_INCLUDED