diff --git a/src/3rdparty b/src/3rdparty
index c1eab215ae..1030737715 160000
--- a/src/3rdparty
+++ b/src/3rdparty
@@ -1 +1 @@
-Subproject commit c1eab215ae34b2bc03fcb8c787b386a25e00bf3e
+Subproject commit 10307377157d71c0ad0d3fd33ccf7e04ce8f65ff
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index f2009c536f..564fd7acb3 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -441,12 +441,17 @@ install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/
 )
 
 install(FILES
-        ${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/fifo_map.hpp
         ${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/json.hpp
         ${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/sqlite3.h
         DESTINATION include/zeek/3rdparty
 )
 
+install(FILES
+        ${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/tsl-ordered-map/ordered_map.h
+        ${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/tsl-ordered-map/ordered_hash.h
+        DESTINATION include/zeek/3rdparty/tsl-ordered-map
+)
+
 ########################################################################
 ## Clang-tidy target now that we have all of the sources
 
diff --git a/src/Val.cc b/src/Val.cc
index 6a27dbfbc7..2da784de9b 100644
--- a/src/Val.cc
+++ b/src/Val.cc
@@ -28,14 +28,19 @@
 #include "broker/Data.h"
 
 #include "3rdparty/json.hpp"
-#include "3rdparty/fifo_map.hpp"
+#include "3rdparty/tsl-ordered-map/ordered_map.h"
+
 
 // Define a class for use with the json library that orders the keys in the same order that
 // they were inserted. By default, the json library orders them alphabetically and we don't
 // want it like that.
-template<class K, class V, class compare, class A>
-using json_fifo_map = nlohmann::fifo_map<K, V, nlohmann::fifo_map_compare<K>, A>;
-using ZeekJson = nlohmann::basic_json<json_fifo_map>;
+template<class Key, class T, class Ignore, class Allocator,
+         class Hash = std::hash<Key>, class KeyEqual = std::equal_to<Key>,
+         class AllocatorPair = typename std::allocator_traits<Allocator>::template rebind_alloc<std::pair<Key, T>>,
+         class ValueTypeContainer = std::vector<std::pair<Key, T>, AllocatorPair>>
+using ordered_map = tsl::ordered_map<Key, T, Hash, KeyEqual, AllocatorPair, ValueTypeContainer>;
+
+using ZeekJson = nlohmann::basic_json<ordered_map>;
 
 Val::Val(Func* f)
 	{
diff --git a/src/threading/formatters/JSON.h b/src/threading/formatters/JSON.h
index 1015eb54c6..71edadc61d 100644
--- a/src/threading/formatters/JSON.h
+++ b/src/threading/formatters/JSON.h
@@ -4,7 +4,7 @@
 
 #include "../Formatter.h"
 #include "3rdparty/json.hpp"
-#include "3rdparty/fifo_map.hpp"
+#include "3rdparty/tsl-ordered-map/ordered_map.h"
 
 
 namespace threading { namespace formatter {
@@ -12,9 +12,13 @@ namespace threading { namespace formatter {
 // Define a class for use with the json library that orders the keys in the same order that
 // they were inserted. By default, the json library orders them alphabetically and we don't
 // want it like that.
-template<class K, class V, class compare, class A>
-using json_fifo_map = nlohmann::fifo_map<K, V, nlohmann::fifo_map_compare<K>, A>;
-using ZeekJson = nlohmann::basic_json<json_fifo_map>;
+template<class Key, class T, class Ignore, class Allocator,
+         class Hash = std::hash<Key>, class KeyEqual = std::equal_to<Key>,
+         class AllocatorPair = typename std::allocator_traits<Allocator>::template rebind_alloc<std::pair<Key, T>>,
+         class ValueTypeContainer = std::vector<std::pair<Key, T>, AllocatorPair>>
+using ordered_map = tsl::ordered_map<Key, T, Hash, KeyEqual, AllocatorPair, ValueTypeContainer>;
+
+using ZeekJson = nlohmann::basic_json<ordered_map>;
 
 /**
   * A thread-safe class for converting values into a JSON representation