diff --git a/source/graphics/MaterialManager.cpp b/source/graphics/MaterialManager.cpp
index 362f5f0d7c..19e40852f9 100644
--- a/source/graphics/MaterialManager.cpp
+++ b/source/graphics/MaterialManager.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -37,8 +37,11 @@ CMaterialManager::CMaterialManager()
 	CFG_GET_VAL("materialmgr.quality", qualityLevel);
 	qualityLevel = Clamp(qualityLevel, 0.0f, 10.0f);
 
-	if (VfsDirectoryExists(L"art/materials/") && !CXeromyces::AddValidator(g_VFS, "material", "art/materials/material.rng"))
+	if (VfsDirectoryExists(L"art/materials/") &&
+		!g_Xeromyces.AddValidator(g_VFS, "material", "art/materials/material.rng"))
+	{
 		LOGERROR("CMaterialManager: failed to load grammar file 'art/materials/material.rng'");
+	}
 }
 
 CMaterial CMaterialManager::LoadMaterial(const VfsPath& pathname)
diff --git a/source/graphics/MiniMapTexture.cpp b/source/graphics/MiniMapTexture.cpp
index 13a138df5f..f729d6e949 100644
--- a/source/graphics/MiniMapTexture.cpp
+++ b/source/graphics/MiniMapTexture.cpp
@@ -197,7 +197,7 @@ CMiniMapTexture::CMiniMapTexture(Renderer::Backend::IDevice* device, CSimulation
 	m_InstanceVertexArray(Renderer::Backend::IBuffer::Type::VERTEX, Renderer::Backend::IBuffer::Usage::TRANSFER_DST)
 {
 	// Register Relax NG validator.
-	CXeromyces::AddValidator(g_VFS, "pathfinder", "simulation/data/pathfinder.rng");
+	g_Xeromyces.AddValidator(g_VFS, "pathfinder", "simulation/data/pathfinder.rng");
 
 	m_ShallowPassageHeight = GetShallowPassageHeight();
 
diff --git a/source/graphics/ObjectManager.cpp b/source/graphics/ObjectManager.cpp
index cb32804040..51c12dbe14 100644
--- a/source/graphics/ObjectManager.cpp
+++ b/source/graphics/ObjectManager.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -54,7 +54,7 @@ CObjectManager::CObjectManager(CMeshManager& meshManager, CSkeletonAnimManager&
 	m_QualityHook = std::make_unique<CConfigDBHook>(g_ConfigDB.RegisterHookAndCall("max_actor_quality", [this]() { ActorQualityChanged(); }));
 	m_VariantDiversityHook = std::make_unique<CConfigDBHook>(g_ConfigDB.RegisterHookAndCall("variant_diversity", [this]() { VariantDiversityChanged(); }));
 
-	if (!CXeromyces::AddValidator(g_VFS, "actor", "art/actors/actor.rng"))
+	if (!g_Xeromyces.AddValidator(g_VFS, "actor", "art/actors/actor.rng"))
 		LOGERROR("CObjectManager: failed to load actor grammar file 'art/actors/actor.rng'");
 }
 
diff --git a/source/graphics/ShaderManager.cpp b/source/graphics/ShaderManager.cpp
index ba72f7814f..c763004223 100644
--- a/source/graphics/ShaderManager.cpp
+++ b/source/graphics/ShaderManager.cpp
@@ -52,7 +52,7 @@ CShaderManager::CShaderManager(Renderer::Backend::IDevice* device)
 	{
 		TIMER_ACCRUE(tc_ShaderValidation);
 
-		if (!CXeromyces::AddValidator(g_VFS, "shader", "shaders/program.rng"))
+		if (!g_Xeromyces.AddValidator(g_VFS, "shader", "shaders/program.rng"))
 			LOGERROR("CShaderManager: failed to load grammar shaders/program.rng");
 	}
 #endif
diff --git a/source/graphics/TerrainTextureManager.cpp b/source/graphics/TerrainTextureManager.cpp
index f7fcfff6c8..b7b1e46dbf 100644
--- a/source/graphics/TerrainTextureManager.cpp
+++ b/source/graphics/TerrainTextureManager.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -40,9 +40,9 @@ CTerrainTextureManager::CTerrainTextureManager(Renderer::Backend::IDevice* devic
 {
 	if (!VfsDirectoryExists(L"art/terrains/"))
 		return;
-	if (!CXeromyces::AddValidator(g_VFS, "terrain", "art/terrains/terrain.rng"))
+	if (!g_Xeromyces.AddValidator(g_VFS, "terrain", "art/terrains/terrain.rng"))
 		LOGERROR("CTerrainTextureManager: failed to load grammar file 'art/terrains/terrain.rng'");
-	if (!CXeromyces::AddValidator(g_VFS, "terrain_texture", "art/terrains/terrain_texture.rng"))
+	if (!g_Xeromyces.AddValidator(g_VFS, "terrain_texture", "art/terrains/terrain_texture.rng"))
 		LOGERROR("CTerrainTextureManager: failed to load grammar file 'art/terrains/terrain_texture.rng'");
 }
 
diff --git a/source/graphics/tests/test_MapGenerator.h b/source/graphics/tests/test_MapGenerator.h
index 2e13886336..bf29f1e006 100644
--- a/source/graphics/tests/test_MapGenerator.h
+++ b/source/graphics/tests/test_MapGenerator.h
@@ -31,17 +31,16 @@ public:
 		g_VFS = CreateVfs();
 		g_VFS->Mount(L"", DataDir() / "mods" / "mod" / "", VFS_MOUNT_MUST_EXIST);
 		g_VFS->Mount(L"", DataDir() / "mods" / "public" / "", VFS_MOUNT_MUST_EXIST, 1); // ignore directory-not-found errors
-		CXeromyces::Startup();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
 		g_VFS.reset();
 	}
 
 	void test_mapgen_scripts()
 	{
+		CXeromycesEngine xeromycesEngine;
 		if (!VfsDirectoryExists(L"maps/random/tests/"))
 		{
 			debug_printf("Skipping map generator tests (can't find binaries/data/mods/public/maps/random/tests/)\n");
diff --git a/source/graphics/tests/test_Model.h b/source/graphics/tests/test_Model.h
index 9afed15b73..c6ae1846bc 100644
--- a/source/graphics/tests/test_Model.h
+++ b/source/graphics/tests/test_Model.h
@@ -42,6 +42,7 @@
 #include "scriptinterface/ScriptInterface.h"
 #include "simulation2/Simulation2.h"
 
+#include <optional>
 #include <memory>
 #include <string_view>
 
@@ -100,6 +101,7 @@ constexpr std::string_view TEST_ACTOR_WITH_SHADOWS_XML{R"(<?xml version="1.0" en
 
 class TestModel : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> m_XeromycesEngine;
 	OsPath m_ModPath;
 	OsPath m_CachePath;
 	std::unique_ptr<CProfileViewer> m_Viewer;
@@ -112,7 +114,7 @@ public:
 
 		CConfigDB::Initialise();
 		CConfigDB::Instance()->SetValueString(CFG_SYSTEM, "rendererbackend", "dummy");
-		CXeromyces::Startup();
+		m_XeromycesEngine.emplace();
 
 		TestLogger logger;
 
@@ -152,7 +154,7 @@ public:
 		m_Viewer.reset();
 		g_VideoMode.Shutdown();
 
-		CXeromyces::Terminate();
+		m_XeromycesEngine.reset();
 		CConfigDB::Shutdown();
 		g_VFS.reset();
 
diff --git a/source/graphics/tests/test_TextureManager.h b/source/graphics/tests/test_TextureManager.h
index c4461bd9b2..64d6dd6c3c 100644
--- a/source/graphics/tests/test_TextureManager.h
+++ b/source/graphics/tests/test_TextureManager.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -25,10 +25,13 @@
 #include "ps/XML/Xeromyces.h"
 #include "renderer/backend/dummy/Device.h"
 
+#include <optional>
+
 class TestTextureManager : public CxxTest::TestSuite
 {
 	PIVFS m_VFS;
 	std::unique_ptr<Renderer::Backend::IDevice> m_Device;
+	std::optional<CXeromycesEngine> m_XeromycesEngine;
 
 public:
 
@@ -42,14 +45,14 @@ public:
 		TS_ASSERT_OK(m_VFS->Mount(L"", DataDir() / "mods" / "_test.tex" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(m_VFS->Mount(L"cache/", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
 
-		CXeromyces::Startup();
+		m_XeromycesEngine.emplace();
 
 		m_Device = std::make_unique<Renderer::Backend::Dummy::CDevice>();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		m_XeromycesEngine.reset();
 
 		m_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
diff --git a/source/gui/GUIManager.cpp b/source/gui/GUIManager.cpp
index 497d02f3d2..8399b4b328 100644
--- a/source/gui/GUIManager.cpp
+++ b/source/gui/GUIManager.cpp
@@ -76,9 +76,9 @@ CGUIManager::CGUIManager(ScriptContext& scriptContext, ScriptInterface& scriptIn
 	m_ScriptInterface.SetCallbackData(this);
 	m_ScriptInterface.LoadGlobalScripts();
 
-	if (!CXeromyces::AddValidator(g_VFS, "gui_page", "gui/gui_page.rng"))
+	if (!g_Xeromyces.AddValidator(g_VFS, "gui_page", "gui/gui_page.rng"))
 		LOGERROR("CGUIManager: failed to load GUI page grammar file 'gui/gui_page.rng'");
-	if (!CXeromyces::AddValidator(g_VFS, "gui", "gui/gui.rng"))
+	if (!g_Xeromyces.AddValidator(g_VFS, "gui", "gui/gui.rng"))
 		LOGERROR("CGUIManager: failed to load GUI XML grammar file 'gui/gui.rng'");
 
 	RegisterFileReloadFunc(ReloadChangedFileCB, this);
diff --git a/source/gui/tests/test_CGUIText.h b/source/gui/tests/test_CGUIText.h
index 464934bb4b..dd779c61ad 100644
--- a/source/gui/tests/test_CGUIText.h
+++ b/source/gui/tests/test_CGUIText.h
@@ -32,9 +32,11 @@
 
 #include <algorithm>
 #include <array>
+#include <optional>
 
 class TestCGUIText : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> m_XeromycesEngine;
 	CProfileViewer* m_Viewer = nullptr;
 	CRenderer* m_Renderer = nullptr;
 
@@ -45,7 +47,7 @@ public:
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "_test.minimal" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
 
-		CXeromyces::Startup();
+		m_XeromycesEngine.emplace();
 
 		// The renderer spews messages.
 		TestLogger logger;
@@ -66,7 +68,7 @@ public:
 		delete m_Viewer;
 		g_VideoMode.Shutdown();
 		CConfigDB::Shutdown();
-		CXeromyces::Terminate();
+		m_XeromycesEngine.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir() / "_testcache");
 	}
diff --git a/source/gui/tests/test_GUISetting.h b/source/gui/tests/test_GUISetting.h
index e597d6fe6c..b1f1355640 100644
--- a/source/gui/tests/test_GUISetting.h
+++ b/source/gui/tests/test_GUISetting.h
@@ -33,10 +33,12 @@
 #include "scriptinterface/ScriptInterface.h"
 
 #include <memory>
+#include <optional>
 #include <type_traits>
 
 class TestGUISetting : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> m_XeromycesEngine;
 	std::unique_ptr<CProfileViewer> m_Viewer;
 	std::unique_ptr<CRenderer> m_Renderer;
 
@@ -55,7 +57,7 @@ public:
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "_test.minimal" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
 
-		CXeromyces::Startup();
+		m_XeromycesEngine.emplace();
 
 		// The renderer spews messages.
 		TestLogger logger;
@@ -76,7 +78,7 @@ public:
 		m_Viewer.reset();
 		g_VideoMode.Shutdown();
 		CConfigDB::Shutdown();
-		CXeromyces::Terminate();
+		m_XeromycesEngine.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir() / "_testcache");
 	}
diff --git a/source/gui/tests/test_GuiManager.h b/source/gui/tests/test_GuiManager.h
index 9a51c3c577..17e9823ebb 100644
--- a/source/gui/tests/test_GuiManager.h
+++ b/source/gui/tests/test_GuiManager.h
@@ -38,6 +38,7 @@
 class TestGuiManager : public CxxTest::TestSuite
 {
 	std::unique_ptr<CConfigDB> configDB;
+	std::optional<CXeromycesEngine> xeromycesEngine;
 	std::optional<ScriptInterface> scriptInterface;
 public:
 
@@ -49,7 +50,7 @@ public:
 
 		configDB = std::make_unique<CConfigDB>();
 
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 
 		scriptInterface.emplace("Engine", "GUIManager", *g_ScriptContext);
 		g_GUI = new CGUIManager{*g_ScriptContext, *scriptInterface};
@@ -59,7 +60,7 @@ public:
 	{
 		delete g_GUI;
 		scriptInterface.reset();
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 		configDB.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
diff --git a/source/main.cpp b/source/main.cpp
index 39ae9084e8..4885198c10 100644
--- a/source/main.cpp
+++ b/source/main.cpp
@@ -573,16 +573,13 @@ static void RunGameOrAtlas(const PS::span<const char* const> argv)
 	// We need to initialize SpiderMonkey and libxml2 in the main thread before
 	// any thread uses them. So initialize them here before we might run Atlas.
 	ScriptEngine scriptEngine;
-	CXeromyces::Startup();
+	CXeromycesEngine xeromycesEngine;
 
 	// Initialise the global task manager at this point (JS & Profiler2 are set up).
 	Threading::TaskManager::Initialise();
 
 	if (ATLAS_RunIfOnCmdLine(args, false))
-	{
-		CXeromyces::Terminate();
 		return;
-	}
 
 	if (isNonVisualReplay)
 	{
@@ -603,8 +600,6 @@ static void RunGameOrAtlas(const PS::span<const char* const> argv)
 		}
 
 		g_VFS.reset();
-
-		CXeromyces::Terminate();
 		return;
 	}
 
@@ -629,8 +624,6 @@ static void RunGameOrAtlas(const PS::span<const char* const> argv)
 			builder.AddBaseMod(paths.RData()/"mods"/mods[i]);
 
 		builder.Build(zip, args.Has("archivebuild-compress"));
-
-		CXeromyces::Terminate();
 		return;
 	}
 
@@ -728,7 +721,6 @@ static void RunGameOrAtlas(const PS::span<const char* const> argv)
 #endif
 
 	Threading::TaskManager::Instance().ClearQueue();
-	CXeromyces::Terminate();
 }
 
 #if OS_ANDROID
diff --git a/source/network/tests/test_Net.h b/source/network/tests/test_Net.h
index 7155a4e738..9b126f06eb 100644
--- a/source/network/tests/test_Net.h
+++ b/source/network/tests/test_Net.h
@@ -34,15 +34,19 @@
 #include "simulation2/Simulation2.h"
 #include "simulation2/system/TurnManager.h"
 
+#include <optional>
+
 class TestNetComms : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
+
 public:
 	void setUp()
 	{
 		g_VFS = CreateVfs();
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "public" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 
 		enet_initialize();
 	}
@@ -51,7 +55,7 @@ public:
 	{
 		enet_deinitialize();
 
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
 	}
diff --git a/source/ps/GameSetup/GameSetup.cpp b/source/ps/GameSetup/GameSetup.cpp
index cd83ccb41c..9ce21011a1 100644
--- a/source/ps/GameSetup/GameSetup.cpp
+++ b/source/ps/GameSetup/GameSetup.cpp
@@ -662,7 +662,7 @@ void InitGraphics(const CmdLineArgs& args, int flags, const std::vector<CStr>& i
 
 	// TODO: Is this the best place for this?
 	if (VfsDirectoryExists(L"maps/"))
-		CXeromyces::AddValidator(g_VFS, "map", "maps/scenario.rng");
+		g_Xeromyces.AddValidator(g_VFS, "map", "maps/scenario.rng");
 
 	try
 	{
diff --git a/source/ps/XML/Xeromyces.cpp b/source/ps/XML/Xeromyces.cpp
index 3e83859d6f..41d89d8b03 100644
--- a/source/ps/XML/Xeromyces.cpp
+++ b/source/ps/XML/Xeromyces.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -37,7 +37,6 @@
 
 static std::mutex g_ValidatorCacheLock;
 static std::map<const std::string, RelaxNGValidator> g_ValidatorCache;
-static bool g_XeromycesStarted = false;
 
 static void errorHandler(void* UNUSED(userData),
 	std::conditional_t<LIBXML_VERSION >= 21200, const xmlError, xmlError>* error)
@@ -54,20 +53,16 @@ static void errorHandler(void* UNUSED(userData),
 	// so the caching is less transparent than it should be
 }
 
-void CXeromyces::Startup()
+CXeromycesEngine::CXeromycesEngine()
 {
-	ENSURE(!g_XeromycesStarted);
 	xmlInitParser();
 	xmlSetStructuredErrorFunc(NULL, &errorHandler);
 	std::lock_guard<std::mutex> lock(g_ValidatorCacheLock);
 	g_ValidatorCache.insert(std::make_pair(std::string(), RelaxNGValidator()));
-	g_XeromycesStarted = true;
 }
 
-void CXeromyces::Terminate()
+CXeromycesEngine::~CXeromycesEngine()
 {
-	ENSURE(g_XeromycesStarted);
-	g_XeromycesStarted = false;
 	ClearSchemaCache();
 	std::lock_guard<std::mutex> lock(g_ValidatorCacheLock);
 	g_ValidatorCache.clear();
@@ -75,10 +70,8 @@ void CXeromyces::Terminate()
 	xmlCleanupParser();
 }
 
-bool CXeromyces::AddValidator(const PIVFS& vfs, const std::string& name, const VfsPath& grammarPath)
+bool CXeromycesEngine::AddValidator(const PIVFS& vfs, const std::string& name, const VfsPath& grammarPath)
 {
-	ENSURE(g_XeromycesStarted);
-
 	RelaxNGValidator validator;
 	if (!validator.LoadGrammarFile(vfs, grammarPath))
 	{
@@ -95,7 +88,7 @@ bool CXeromyces::AddValidator(const PIVFS& vfs, const std::string& name, const V
 	return true;
 }
 
-bool CXeromyces::ValidateEncoded(const std::string& name, const std::string& filename, const std::string& document)
+bool CXeromycesEngine::ValidateEncoded(const std::string& name, const std::string& filename, const std::string& document)
 {
 	std::lock_guard<std::mutex> lock(g_ValidatorCacheLock);
 	return GetValidator(name).ValidateEncoded(filename, document);
@@ -104,7 +97,7 @@ bool CXeromyces::ValidateEncoded(const std::string& name, const std::string& fil
 /**
  * NOTE: Callers MUST acquire the g_ValidatorCacheLock before calling this.
  */
-RelaxNGValidator& CXeromyces::GetValidator(const std::string& name)
+RelaxNGValidator& CXeromycesEngine::GetValidator(const std::string& name)
 {
 	if (g_ValidatorCache.find(name) == g_ValidatorCache.end())
 		return g_ValidatorCache.find("")->second;
@@ -113,14 +106,12 @@ RelaxNGValidator& CXeromyces::GetValidator(const std::string& name)
 
 PSRETURN CXeromyces::Load(const PIVFS& vfs, const VfsPath& filename, const std::string& validatorName /* = "" */)
 {
-	ENSURE(g_XeromycesStarted);
-
 	CCacheLoader cacheLoader(vfs, L".xmb");
 
 	MD5 validatorGrammarHash;
 	{
 		std::lock_guard<std::mutex> lock(g_ValidatorCacheLock);
-		validatorGrammarHash = GetValidator(validatorName).GetGrammarHash();
+		validatorGrammarHash = g_Xeromyces.GetValidator(validatorName).GetGrammarHash();
 	}
 	VfsPath xmbPath;
 	Status ret = cacheLoader.TryLoadingCached(filename, validatorGrammarHash, XMBStorage::XMBVersion, xmbPath);
@@ -181,7 +172,7 @@ PSRETURN CXeromyces::ConvertFile(const PIVFS& vfs, const VfsPath& filename, cons
 
 	{
 		std::lock_guard<std::mutex> lock(g_ValidatorCacheLock);
-		RelaxNGValidator& validator = GetValidator(validatorName);
+		RelaxNGValidator& validator = g_Xeromyces.GetValidator(validatorName);
 		if (validator.CanValidate() && !validator.ValidateEncoded(doc))
 		{
 			LOGERROR("CXeromyces: failed to validate XML file %s", filename.string8());
@@ -205,8 +196,6 @@ PSRETURN CXeromyces::ConvertFile(const PIVFS& vfs, const VfsPath& filename, cons
 
 PSRETURN CXeromyces::LoadString(const char* xml, const std::string& validatorName /* = "" */)
 {
-	ENSURE(g_XeromycesStarted);
-
 	xmlDocPtr doc = xmlReadMemory(xml, (int)strlen(xml), "(no file)", NULL, XML_PARSE_NONET|XML_PARSE_NOCDATA);
 	if (!doc)
 	{
@@ -216,7 +205,7 @@ PSRETURN CXeromyces::LoadString(const char* xml, const std::string& validatorNam
 
 	{
 		std::lock_guard<std::mutex> lock(g_ValidatorCacheLock);
-		RelaxNGValidator& validator = GetValidator(validatorName);
+		RelaxNGValidator& validator = g_Xeromyces.GetValidator(validatorName);
 		if (validator.CanValidate() && !validator.ValidateEncoded(doc))
 		{
 			LOGERROR("CXeromyces: failed to validate XML string");
diff --git a/source/ps/XML/Xeromyces.h b/source/ps/XML/Xeromyces.h
index 75b9bb0d40..de6d2ca1b7 100644
--- a/source/ps/XML/Xeromyces.h
+++ b/source/ps/XML/Xeromyces.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -30,6 +30,7 @@ ERROR_TYPE(Xeromyces, XMLOpenFailed);
 ERROR_TYPE(Xeromyces, XMLParseError);
 ERROR_TYPE(Xeromyces, XMLValidationFailed);
 
+#include "ps/Singleton.h"
 #include "ps/XMB/XMBData.h"
 #include "ps/XMB/XMBStorage.h"
 
@@ -59,29 +60,30 @@ public:
 	 */
 	bool GenerateCachedXMB(const PIVFS& vfs, const VfsPath& sourcePath, VfsPath& archiveCachePath, const std::string& validatorName = "");
 
-	/**
-	 * Call once when initialising the program, to load libxml2.
-	 * This should be run in the main thread, before any thread uses libxml2.
-	 */
-	static void Startup();
-
-	/**
-	 * Call once when shutting down the program, to unload libxml2.
-	 */
-	static void Terminate();
-
-	static bool AddValidator(const PIVFS& vfs, const std::string& name, const VfsPath& grammarPath);
-
-	static bool ValidateEncoded(const std::string& name, const std::string& filename, const std::string& document);
-
 private:
-	static RelaxNGValidator& GetValidator(const std::string& name);
-
 	PSRETURN ConvertFile(const PIVFS& vfs, const VfsPath& filename, const VfsPath& xmbPath, const std::string& validatorName);
 
 	XMBStorage m_Data;
 };
 
+class CXeromycesEngine : public Singleton<CXeromycesEngine>
+{
+	friend CXeromyces;
+public:
+	/**
+	 * This should be run in the main thread, before any thread uses libxml2.
+	 */
+	CXeromycesEngine();
+	~CXeromycesEngine();
+
+	bool AddValidator(const PIVFS& vfs, const std::string& name, const VfsPath& grammarPath);
+	bool ValidateEncoded(const std::string& name, const std::string& filename, const std::string& document);
+
+private:
+	RelaxNGValidator& GetValidator(const std::string& name);
+};
+
+#define g_Xeromyces CXeromycesEngine::GetSingleton()
 
 #define _XERO_MAKE_UID2__(p,l) p ## l
 #define _XERO_MAKE_UID1__(p,l) _XERO_MAKE_UID2__(p,l)
diff --git a/source/ps/XML/tests/test_RelaxNG.h b/source/ps/XML/tests/test_RelaxNG.h
index 6fa3ba0263..bbd3caf8a8 100644
--- a/source/ps/XML/tests/test_RelaxNG.h
+++ b/source/ps/XML/tests/test_RelaxNG.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -21,17 +21,20 @@
 #include "ps/XML/Xeromyces.h"
 #include "ps/XML/RelaxNG.h"
 
+#include <optional>
+
 class TestRelaxNG : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
 public:
 	void setUp()
 	{
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 	}
 
 	void test_basic()
diff --git a/source/ps/XML/tests/test_Xeromyces.h b/source/ps/XML/tests/test_Xeromyces.h
index 80e112e451..600da1c518 100644
--- a/source/ps/XML/tests/test_Xeromyces.h
+++ b/source/ps/XML/tests/test_Xeromyces.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -24,21 +24,12 @@
 class TestXeromyces : public CxxTest::TestSuite
 {
 public:
-	void setUp()
-	{
-		CXeromyces::Startup();
-	}
-
-	void tearDown()
-	{
-		CXeromyces::Terminate();
-	}
-
 	// TODO: Should test the reading/parsing/writing code,
 	// and parse error handling
 
 	void test_LoadString()
 	{
+		CXeromycesEngine xeromycesEngine;
 		CXeromyces xero;
 		TS_ASSERT_EQUALS(xero.LoadString("<test><foo>bar</foo></test>"), PSRETURN_OK);
 		TS_ASSERT_STR_EQUALS(xero.GetElementString(xero.GetRoot().GetNodeName()), "test");
@@ -46,6 +37,7 @@ public:
 
 	void test_LoadString_invalid()
 	{
+		CXeromycesEngine xeromycesEngine;
 		TestLogger logger;
 		CXeromyces xero;
 		TS_ASSERT_EQUALS(xero.LoadString("<test>"), PSRETURN_Xeromyces_XMLParseError);
diff --git a/source/renderer/backend/gl/ShaderProgram.cpp b/source/renderer/backend/gl/ShaderProgram.cpp
index 67806d70b2..6c5471672f 100644
--- a/source/renderer/backend/gl/ShaderProgram.cpp
+++ b/source/renderer/backend/gl/ShaderProgram.cpp
@@ -1208,8 +1208,7 @@ std::unique_ptr<CShaderProgram> CShaderProgram::Create(CDevice* device, const CS
 		XMLWriter_File shaderFile;
 		shaderFile.SetPrettyPrint(false);
 		shaderFile.XMB(XeroFile);
-		bool ok = CXeromyces::ValidateEncoded("shader", name, shaderFile.GetOutput());
-		if (!ok)
+		if (!g_Xeromyces.ValidateEncoded("shader", name, shaderFile.GetOutput()))
 			return nullptr;
 	}
 #endif
diff --git a/source/simulation2/components/CCmpPathfinder.cpp b/source/simulation2/components/CCmpPathfinder.cpp
index 5260a7395d..3c7eab6b46 100644
--- a/source/simulation2/components/CCmpPathfinder.cpp
+++ b/source/simulation2/components/CCmpPathfinder.cpp
@@ -70,7 +70,7 @@ void CCmpPathfinder::Init(const CParamNode& UNUSED(paramNode))
 	m_Futures.resize(workerThreads);
 
 	// Register Relax NG validator
-	CXeromyces::AddValidator(g_VFS, "pathfinder", "simulation/data/pathfinder.rng");
+	g_Xeromyces.AddValidator(g_VFS, "pathfinder", "simulation/data/pathfinder.rng");
 
 	// Since this is used as a system component (not loaded from an entity template),
 	// we can't use the real paramNode (it won't get handled properly when deserializing),
diff --git a/source/simulation2/components/CCmpTerritoryManager.cpp b/source/simulation2/components/CCmpTerritoryManager.cpp
index d6ecea31f7..25927702ff 100644
--- a/source/simulation2/components/CCmpTerritoryManager.cpp
+++ b/source/simulation2/components/CCmpTerritoryManager.cpp
@@ -136,7 +136,7 @@ public:
 		m_TerritoryTotalPassableCellCount = 0;
 
 		// Register Relax NG validator
-		CXeromyces::AddValidator(g_VFS, "territorymanager", "simulation/data/territorymanager.rng");
+		g_Xeromyces.AddValidator(g_VFS, "territorymanager", "simulation/data/territorymanager.rng");
 
 		CParamNode externalParamNode;
 		CParamNode::LoadXML(externalParamNode, L"simulation/data/territorymanager.xml", "territorymanager");
diff --git a/source/simulation2/components/tests/test_CinemaManager.h b/source/simulation2/components/tests/test_CinemaManager.h
index 14b4e1a3be..7f65a77bc3 100644
--- a/source/simulation2/components/tests/test_CinemaManager.h
+++ b/source/simulation2/components/tests/test_CinemaManager.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -22,18 +22,9 @@
 class TestCmpCinemaManager : public CxxTest::TestSuite
 {
 public:
-	void setUp()
-	{
-		CXeromyces::Startup();
-	}
-
-	void tearDown()
-	{
-		CXeromyces::Terminate();
-	}
-
 	void test_basic()
 	{
+		CXeromycesEngine xeromycesEngine;
 		ComponentTestHelper test(*g_ScriptContext);
 
 		ICmpCinemaManager* cmp = test.Add<ICmpCinemaManager>(CID_CinemaManager, "", SYSTEM_ENTITY);
diff --git a/source/simulation2/components/tests/test_CommandQueue.h b/source/simulation2/components/tests/test_CommandQueue.h
index 851d3e6aa7..45538f34bc 100644
--- a/source/simulation2/components/tests/test_CommandQueue.h
+++ b/source/simulation2/components/tests/test_CommandQueue.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -22,18 +22,9 @@
 class TestCmpCommandQueue : public CxxTest::TestSuite
 {
 public:
-	void setUp()
-	{
-		CXeromyces::Startup();
-	}
-
-	void tearDown()
-	{
-		CXeromyces::Terminate();
-	}
-
 	void test_basic()
 	{
+		CXeromycesEngine xeromycesEngine;
 		ComponentTestHelper test(*g_ScriptContext);
 		ScriptRequest rq(test.GetScriptInterface());
 
diff --git a/source/simulation2/components/tests/test_ObstructionManager.h b/source/simulation2/components/tests/test_ObstructionManager.h
index e2acdcf2d5..694881e586 100644
--- a/source/simulation2/components/tests/test_ObstructionManager.h
+++ b/source/simulation2/components/tests/test_ObstructionManager.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -20,6 +20,8 @@
 #include "simulation2/components/ICmpObstructionManager.h"
 #include "simulation2/components/ICmpObstruction.h"
 
+#include <optional>
+
 class MockObstruction : public ICmpObstruction
 {
 public:
@@ -59,6 +61,8 @@ class TestCmpObstructionManager : public CxxTest::TestSuite
 	typedef ICmpObstructionManager::tag_t tag_t;
 	typedef ICmpObstructionManager::ObstructionSquare ObstructionSquare;
 
+	std::optional<CXeromycesEngine> xeromycesEngine;
+
 	// some variables for setting up a scene with 3 shapes
 	entity_id_t ent1, ent2, ent3; // entity IDs
 	entity_angle_t ent1a; // angles
@@ -75,7 +79,7 @@ class TestCmpObstructionManager : public CxxTest::TestSuite
 public:
 	void setUp()
 	{
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 		CxxTest::setAbortTestOnFail(true);
 
 		// set up a simple scene with some predefined obstruction shapes
@@ -126,7 +130,7 @@ public:
 		delete testHelper;
 		cmp = NULL; // not our responsibility to deallocate
 
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 	}
 
 	/**
diff --git a/source/simulation2/components/tests/test_Pathfinder.h b/source/simulation2/components/tests/test_Pathfinder.h
index 97449af2da..0b5db605dc 100644
--- a/source/simulation2/components/tests/test_Pathfinder.h
+++ b/source/simulation2/components/tests/test_Pathfinder.h
@@ -32,10 +32,12 @@
 #include "simulation2/Simulation2.h"
 
 #include <fstream>
+#include <optional>
 #include <random>
 
 class TestCmpPathfinder : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
 public:
 	void setUp()
 	{
@@ -44,12 +46,12 @@ public:
 		g_VFS->Mount(L"", DataDir() / "mods" / "public" / "", VFS_MOUNT_MUST_EXIST, 1); // ignore directory-not-found errors
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
 
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
 	}
diff --git a/source/simulation2/components/tests/test_Position.h b/source/simulation2/components/tests/test_Position.h
index fef2280439..1e46745233 100644
--- a/source/simulation2/components/tests/test_Position.h
+++ b/source/simulation2/components/tests/test_Position.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -48,16 +48,6 @@ public:
 class TestCmpPosition : public CxxTest::TestSuite
 {
 public:
-	void setUp()
-	{
-		CXeromyces::Startup();
-	}
-
-	void tearDown()
-	{
-		CXeromyces::Terminate();
-	}
-
 	static CFixedVector3D fixedvec(int x, int y, int z)
 	{
 		return CFixedVector3D(fixed::FromInt(x), fixed::FromInt(y), fixed::FromInt(z));
@@ -65,6 +55,7 @@ public:
 
 	void test_basic()
 	{
+		CXeromycesEngine xeromycesEngine;
 		ComponentTestHelper test(*g_ScriptContext);
 
 		MockTerrain terrain;
@@ -137,6 +128,7 @@ public:
 
 	void test_water()
 	{
+		CXeromycesEngine xeromycesEngine;
 		ComponentTestHelper test(*g_ScriptContext);
 
 		MockTerrain terrain;
@@ -210,6 +202,7 @@ public:
 
 	void test_serialize()
 	{
+		CXeromycesEngine xeromycesEngine;
 		ComponentTestHelper test(*g_ScriptContext);
 
 		MockTerrain terrain;
diff --git a/source/simulation2/components/tests/test_RangeManager.h b/source/simulation2/components/tests/test_RangeManager.h
index 2e47bce865..075e656d0e 100644
--- a/source/simulation2/components/tests/test_RangeManager.h
+++ b/source/simulation2/components/tests/test_RangeManager.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -25,6 +25,8 @@
 #include <boost/random/mersenne_twister.hpp>
 #include <boost/random/uniform_real_distribution.hpp>
 
+#include <optional>
+
 class MockVisionRgm : public ICmpVision
 {
 public:
@@ -114,15 +116,16 @@ private:
 
 class TestCmpRangeManager : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
 public:
 	void setUp()
 	{
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 	}
 
 	// TODO It would be nice to call Verify() with the shore revealing system
diff --git a/source/simulation2/components/tests/test_TerritoryManager.h b/source/simulation2/components/tests/test_TerritoryManager.h
index 430e26cea3..a99c21f116 100644
--- a/source/simulation2/components/tests/test_TerritoryManager.h
+++ b/source/simulation2/components/tests/test_TerritoryManager.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -27,6 +27,8 @@
 #include "simulation2/components/ICmpTerritoryInfluence.h"
 #include "simulation2/components/ICmpOwnership.h"
 
+#include <optional>
+
 class MockPathfinderTerrMan : public ICmpPathfinder
 {
 public:
@@ -140,6 +142,7 @@ public:
 
 class TestCmpTerritoryManager : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
 public:
 	void setUp()
 	{
@@ -147,12 +150,12 @@ public:
 		g_VFS = CreateVfs();
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "_test.sim" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
 	}
diff --git a/source/simulation2/components/tests/test_scripts.h b/source/simulation2/components/tests/test_scripts.h
index feadfef079..2a0a523a3e 100644
--- a/source/simulation2/components/tests/test_scripts.h
+++ b/source/simulation2/components/tests/test_scripts.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -32,12 +32,10 @@ public:
 		g_VFS = CreateVfs();
 		g_VFS->Mount(L"", DataDir() / "mods" / "mod" / "", VFS_MOUNT_MUST_EXIST);
 		g_VFS->Mount(L"", DataDir() / "mods" / "public" / "", VFS_MOUNT_MUST_EXIST, 1); // ignore directory-not-found errors
-		CXeromyces::Startup();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
 		g_VFS.reset();
 	}
 
@@ -79,6 +77,7 @@ public:
 
 	void test_global_scripts()
 	{
+		CXeromycesEngine xeromycesEngine;
 		if (!VfsDirectoryExists(L"globalscripts/tests/"))
 		{
 			debug_printf("Skipping globalscripts tests (can't find binaries/data/mods/public/globalscripts/tests/)\n");
@@ -102,6 +101,7 @@ public:
 
 	void test_scripts()
 	{
+		CXeromycesEngine xeromycesEngine;
 		if (!VfsFileExists(L"simulation/components/tests/setup.js"))
 		{
 			debug_printf("Skipping component scripts tests (can't find binaries/data/mods/public/simulation/components/tests/setup.js)\n");
diff --git a/source/simulation2/tests/test_CmpTemplateManager.h b/source/simulation2/tests/test_CmpTemplateManager.h
index 6ec8820d6b..471c46326e 100644
--- a/source/simulation2/tests/test_CmpTemplateManager.h
+++ b/source/simulation2/tests/test_CmpTemplateManager.h
@@ -33,20 +33,23 @@
 #include "scriptinterface/JSON.h"
 #include "scriptinterface/ScriptRequest.h"
 
+#include <optional>
+
 class TestCmpTemplateManager : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
 public:
 	void setUp()
 	{
 		g_VFS = CreateVfs();
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "_test.sim" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
 	}
@@ -226,12 +229,10 @@ public:
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "mod" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "public" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir()/"_testcache" / "", 0, VFS_MAX_PRIORITY));
-		CXeromyces::Startup();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
 	}
@@ -239,6 +240,7 @@ public:
 	// This just attempts loading every public entity, to check there's no validation errors
 	void DISABLED_test_load_all() // disabled since it's a bit slow and noisy
 	{
+		CXeromycesEngine xeromycesEngine;
 		CTerrain dummy;
 		CSimulation2 sim{nullptr, *g_ScriptContext, &dummy};
 		sim.LoadDefaultScripts();
diff --git a/source/simulation2/tests/test_ComponentManager.h b/source/simulation2/tests/test_ComponentManager.h
index 08564884d8..f1b77e8a11 100644
--- a/source/simulation2/tests/test_ComponentManager.h
+++ b/source/simulation2/tests/test_ComponentManager.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -30,6 +30,8 @@
 #include "ps/Filesystem.h"
 #include "ps/XML/Xeromyces.h"
 
+#include <optional>
+
 #define TS_ASSERT_STREAM(stream, len, buffer) \
 	TS_ASSERT_EQUALS(stream.str().length(), (size_t)len); \
 	TS_ASSERT_SAME_DATA(stream.str().data(), buffer, len)
@@ -40,18 +42,19 @@
 
 class TestComponentManager : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
 public:
 	void setUp()
 	{
 		g_VFS = CreateVfs();
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "_test.sim" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
 	}
diff --git a/source/simulation2/tests/test_ParamNode.h b/source/simulation2/tests/test_ParamNode.h
index e9dd7564f2..84c1c4ef07 100644
--- a/source/simulation2/tests/test_ParamNode.h
+++ b/source/simulation2/tests/test_ParamNode.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -22,17 +22,20 @@
 #include "ps/CLogger.h"
 #include "ps/XML/Xeromyces.h"
 
+#include <optional>
+
 class TestParamNode : public CxxTest::TestSuite
 {
+	std::optional<CXeromycesEngine> xeromycesEngine;
 public:
 	void setUp()
 	{
-		CXeromyces::Startup();
+		xeromycesEngine.emplace();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
+		xeromycesEngine.reset();
 	}
 
 	void test_basic()
diff --git a/source/simulation2/tests/test_Serializer.h b/source/simulation2/tests/test_Serializer.h
index da91ea67ef..e049d5bfb9 100644
--- a/source/simulation2/tests/test_Serializer.h
+++ b/source/simulation2/tests/test_Serializer.h
@@ -879,7 +879,7 @@ public:
 
 	void DISABLED_test_hash()
 	{
-		CXeromyces::Startup();
+		CXeromycesEngine xeromycesEngine;
 
 		g_VFS = CreateVfs();
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "public" / "", VFS_MOUNT_MUST_EXIST));
@@ -935,7 +935,6 @@ public:
 		// Shut down the world
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
-		CXeromyces::Terminate();
 	}
 
 };
diff --git a/source/simulation2/tests/test_Simulation2.h b/source/simulation2/tests/test_Simulation2.h
index eab75eaa3d..470f42a910 100644
--- a/source/simulation2/tests/test_Simulation2.h
+++ b/source/simulation2/tests/test_Simulation2.h
@@ -45,18 +45,17 @@ public:
 		g_VFS = CreateVfs();
 		TS_ASSERT_OK(g_VFS->Mount(L"", DataDir() / "mods" / "_test.sim" / "", VFS_MOUNT_MUST_EXIST));
 		TS_ASSERT_OK(g_VFS->Mount(L"cache", DataDir() / "_testcache" / "", 0, VFS_MAX_PRIORITY));
-		CXeromyces::Startup();
 	}
 
 	void tearDown()
 	{
-		CXeromyces::Terminate();
 		g_VFS.reset();
 		DeleteDirectory(DataDir()/"_testcache");
 	}
 
 	void test_AddEntity()
 	{
+		CXeromycesEngine xeromycesEngine;
 		CSimulation2 sim{nullptr, *g_ScriptContext, &m_Terrain};
 		TS_ASSERT(sim.LoadScripts(L"simulation/components/addentity/"));
 
@@ -77,6 +76,7 @@ public:
 
 	void test_DestroyEntity()
 	{
+		CXeromycesEngine xeromycesEngine;
 		CSimulation2 sim{nullptr, *g_ScriptContext, &m_Terrain};
 		TS_ASSERT(sim.LoadScripts(L"simulation/components/addentity/"));
 
@@ -133,6 +133,7 @@ public:
 
 	void test_hotload_scripts()
 	{
+		CXeromycesEngine xeromycesEngine;
 		CSimulation2 sim{nullptr, *g_ScriptContext, &m_Terrain};
 
 		TS_ASSERT_OK(CreateDirectories(DataDir()/"mods"/"_test.sim"/"simulation"/"components"/"hotload"/"", 0700));
diff --git a/source/soundmanager/SoundManager.cpp b/source/soundmanager/SoundManager.cpp
index 57000f7e74..1822a9e89d 100644
--- a/source/soundmanager/SoundManager.cpp
+++ b/source/soundmanager/SoundManager.cpp
@@ -261,7 +261,7 @@ CSoundManager::CSoundManager(ALCdevice* device)
 		m_PlayListItems = new PlayList;
 	}
 
-	if (!CXeromyces::AddValidator(g_VFS, "sound_group", "audio/sound_group.rng"))
+	if (!g_Xeromyces.AddValidator(g_VFS, "sound_group", "audio/sound_group.rng"))
 		LOGERROR("CSoundManager: failed to load grammar file 'audio/sound_group.rng'");
 
 	RegisterFileReloadFunc(ReloadChangedFileCB, this);