diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4459b92eb..84eb76651 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -467,19 +467,27 @@ SET(MULTIMC_SOURCES
 	logic/OneSixInstance_p.h
 
 	# OneSix version json infrastructure
+	logic/minecraft/JarMod.cpp
+	logic/minecraft/JarMod.h
+	logic/minecraft/MinecraftVersion.cpp
 	logic/minecraft/MinecraftVersion.h
-	logic/minecraft/OneSixVersionBuilder.h
-	logic/minecraft/OneSixVersionBuilder.cpp
-	logic/minecraft/VersionFile.h
-	logic/minecraft/VersionFile.cpp
-	logic/minecraft/VersionFinal.h
-	logic/minecraft/VersionFinal.cpp
-	logic/minecraft/OneSixLibrary.h
-	logic/minecraft/OneSixLibrary.cpp
-	logic/minecraft/OneSixRule.h
-	logic/minecraft/OneSixRule.cpp
-	logic/minecraft/MinecraftVersionList.h
 	logic/minecraft/MinecraftVersionList.cpp
+	logic/minecraft/MinecraftVersionList.h
+	logic/minecraft/OneSixLibrary.cpp
+	logic/minecraft/OneSixLibrary.h
+	logic/minecraft/OneSixRule.cpp
+	logic/minecraft/OneSixRule.h
+	logic/minecraft/OpSys.cpp
+	logic/minecraft/OpSys.h
+	logic/minecraft/RawLibrary.cpp
+	logic/minecraft/RawLibrary.h
+	logic/minecraft/VersionBuilder.cpp
+	logic/minecraft/VersionBuilder.h
+	logic/minecraft/VersionFile.cpp
+	logic/minecraft/VersionFile.h
+	logic/minecraft/VersionFinal.cpp
+	logic/minecraft/VersionFinal.h
+	logic/minecraft/VersionPatch.h
 
 	# Trivial operating system utilities
 	logic/minecraft/OpSys.h
diff --git a/gui/dialogs/InstanceEditDialog.cpp b/gui/dialogs/InstanceEditDialog.cpp
index fc2d6a75b..1fca3b7c9 100644
--- a/gui/dialogs/InstanceEditDialog.cpp
+++ b/gui/dialogs/InstanceEditDialog.cpp
@@ -40,7 +40,7 @@
 #include "logic/forge/ForgeInstaller.h"
 #include "logic/liteloader/LiteLoaderVersionList.h"
 #include "logic/liteloader/LiteLoaderInstaller.h"
-#include "logic/minecraft/OneSixVersionBuilder.h"
+#include "logic/minecraft/VersionBuilder.h"
 #include "logic/auth/MojangAccountList.h"
 
 #include <QAbstractItemModel>
diff --git a/logic/OneSixFTBInstance.cpp b/logic/OneSixFTBInstance.cpp
index 491b15bac..eb0e4ba4b 100644
--- a/logic/OneSixFTBInstance.cpp
+++ b/logic/OneSixFTBInstance.cpp
@@ -2,7 +2,7 @@
 
 #include "logic/minecraft/VersionFinal.h"
 #include "logic/minecraft/OneSixLibrary.h"
-#include "logic/minecraft/OneSixVersionBuilder.h"
+#include "logic/minecraft/VersionBuilder.h"
 #include "tasks/SequentialTask.h"
 #include "forge/ForgeInstaller.h"
 #include "forge/ForgeVersionList.h"
diff --git a/logic/OneSixUpdate.cpp b/logic/OneSixUpdate.cpp
index 66a699fe6..beb293fff 100644
--- a/logic/OneSixUpdate.cpp
+++ b/logic/OneSixUpdate.cpp
@@ -480,7 +480,7 @@ void OneSixUpdate::fmllibsStart()
 
 	// determine if we need some libs for FML or forge
 	setStatus(tr("Checking for FML libraries..."));
-	forge_present = (fullversion->versionFile("net.minecraftforge") != nullptr);
+	forge_present = (fullversion->versionPatch("net.minecraftforge") != nullptr);
 	// we don't...
 	if (!forge_present)
 	{
diff --git a/logic/minecraft/JarMod.cpp b/logic/minecraft/JarMod.cpp
new file mode 100644
index 000000000..99a30aa58
--- /dev/null
+++ b/logic/minecraft/JarMod.cpp
@@ -0,0 +1,44 @@
+#include "JarMod.h"
+#include "logic/MMCJson.h"
+
+JarmodPtr Jarmod::fromJson(const QJsonObject &libObj, const QString &filename)
+{
+	JarmodPtr out(new Jarmod());
+	if (!libObj.contains("name"))
+	{
+		throw JSONValidationError(filename +
+								  "contains a jarmod that doesn't have a 'name' field");
+	}
+	out->name = libObj.value("name").toString();
+
+	auto readString = [libObj, filename](const QString & key, QString & variable)
+	{
+		if (libObj.contains(key))
+		{
+			QJsonValue val = libObj.value(key);
+			if (!val.isString())
+			{
+				QLOG_WARN() << key << "is not a string in" << filename << "(skipping)";
+			}
+			else
+			{
+				variable = val.toString();
+			}
+		}
+	};
+
+	readString("url", out->baseurl);
+	readString("MMC-absoluteUrl", out->absoluteUrl);
+	if(!out->baseurl.isEmpty() && out->absoluteUrl.isEmpty())
+	{
+		out->absoluteUrl = out->baseurl + out->name;
+	}
+	return out;
+}
+
+QString Jarmod::url()
+{
+	if(!absoluteUrl.isEmpty())
+		return absoluteUrl;
+	else return baseurl + name;
+}
diff --git a/logic/minecraft/JarMod.h b/logic/minecraft/JarMod.h
new file mode 100644
index 000000000..da5d8db01
--- /dev/null
+++ b/logic/minecraft/JarMod.h
@@ -0,0 +1,17 @@
+#pragma once
+#include <QString>
+#include <QJsonObject>
+#include <memory>
+class Jarmod;
+typedef std::shared_ptr<Jarmod> JarmodPtr;
+class Jarmod
+{
+public: /* methods */
+	static JarmodPtr fromJson(const QJsonObject &libObj, const QString &filename);
+	QString url();
+public: /* data */
+	QString name;
+	QString baseurl;
+	QString hint;
+	QString absoluteUrl;
+};
diff --git a/logic/minecraft/MinecraftVersion.cpp b/logic/minecraft/MinecraftVersion.cpp
new file mode 100644
index 000000000..a2e5a50a2
--- /dev/null
+++ b/logic/minecraft/MinecraftVersion.cpp
@@ -0,0 +1,2 @@
+#include "MinecraftVersion.h"
+
diff --git a/logic/minecraft/MinecraftVersion.h b/logic/minecraft/MinecraftVersion.h
index 3be259122..dab08bb1c 100644
--- a/logic/minecraft/MinecraftVersion.h
+++ b/logic/minecraft/MinecraftVersion.h
@@ -16,10 +16,11 @@
 #pragma once
 
 #include "logic/BaseVersion.h"
+#include "VersionPatch.h"
 #include <QStringList>
 #include <QSet>
 
-struct MinecraftVersion : public BaseVersion
+struct MinecraftVersion : public BaseVersion, public VersionPatch
 {
 	/// The version's timestamp - this is primarily used for sorting versions in a list.
 	qint64 timestamp;
@@ -89,4 +90,19 @@ struct MinecraftVersion : public BaseVersion
 			return QObject::tr("Regular release");
 		}
 	}
+	
+	virtual bool hasJarMods() override
+	{
+		return false;
+	}
+	
+	virtual bool isVanilla() override
+	{
+		return true;
+	}
+	
+	virtual void applyTo(VersionFinal *version)
+	{
+		// umm... what now?
+	}
 };
diff --git a/logic/minecraft/OneSixRule.cpp b/logic/minecraft/OneSixRule.cpp
index d8d13b50c..93c49e5e2 100644
--- a/logic/minecraft/OneSixRule.cpp
+++ b/logic/minecraft/OneSixRule.cpp
@@ -18,6 +18,15 @@
 
 #include "OneSixRule.h"
 
+RuleAction RuleAction_fromString(QString name)
+{
+	if (name == "allow")
+		return Allow;
+	if (name == "disallow")
+		return Disallow;
+	return Defer;
+}
+
 QList<std::shared_ptr<Rule>> rulesFromJsonV4(const QJsonObject &objectWithRules)
 {
 	QList<std::shared_ptr<Rule>> rules;
@@ -79,11 +88,3 @@ QJsonObject OsRule::toJson()
 	return ruleObj;
 }
 
-RuleAction RuleAction_fromString(QString name)
-{
-	if (name == "allow")
-		return Allow;
-	if (name == "disallow")
-		return Disallow;
-	return Defer;
-}
diff --git a/logic/minecraft/OneSixRule.h b/logic/minecraft/OneSixRule.h
index 2c569b9f7..23d041512 100644
--- a/logic/minecraft/OneSixRule.h
+++ b/logic/minecraft/OneSixRule.h
@@ -26,7 +26,6 @@ enum RuleAction
 	Defer
 };
 
-RuleAction RuleAction_fromString(QString);
 QList<std::shared_ptr<Rule>> rulesFromJsonV4(const QJsonObject &objectWithRules);
 
 class Rule
diff --git a/logic/minecraft/RawLibrary.cpp b/logic/minecraft/RawLibrary.cpp
new file mode 100644
index 000000000..12aac8c84
--- /dev/null
+++ b/logic/minecraft/RawLibrary.cpp
@@ -0,0 +1,68 @@
+#include "logic/MMCJson.h"
+using namespace MMCJson;
+
+#include "RawLibrary.h"
+
+RawLibraryPtr RawLibrary::fromJson(const QJsonObject &libObj, const QString &filename)
+{
+	RawLibraryPtr out(new RawLibrary());
+	if (!libObj.contains("name"))
+	{
+		throw JSONValidationError(filename +
+								  "contains a library that doesn't have a 'name' field");
+	}
+	out->name = libObj.value("name").toString();
+
+	auto readString = [libObj, filename](const QString & key, QString & variable)
+	{
+		if (libObj.contains(key))
+		{
+			QJsonValue val = libObj.value(key);
+			if (!val.isString())
+			{
+				QLOG_WARN() << key << "is not a string in" << filename << "(skipping)";
+			}
+			else
+			{
+				variable = val.toString();
+			}
+		}
+	};
+
+	readString("url", out->url);
+	readString("MMC-hint", out->hint);
+	readString("MMC-absulute_url", out->absoluteUrl);
+	readString("MMC-absoluteUrl", out->absoluteUrl);
+	if (libObj.contains("extract"))
+	{
+		out->applyExcludes = true;
+		auto extractObj = ensureObject(libObj.value("extract"));
+		for (auto excludeVal : ensureArray(extractObj.value("exclude")))
+		{
+			out->excludes.append(ensureString(excludeVal));
+		}
+	}
+	if (libObj.contains("natives"))
+	{
+		out->applyNatives = true;
+		QJsonObject nativesObj = ensureObject(libObj.value("natives"));
+		for (auto it = nativesObj.begin(); it != nativesObj.end(); ++it)
+		{
+			if (!it.value().isString())
+			{
+				QLOG_WARN() << filename << "contains an invalid native (skipping)";
+			}
+			OpSys opSys = OpSys_fromString(it.key());
+			if (opSys != Os_Other)
+			{
+				out->natives.append(qMakePair(opSys, it.value().toString()));
+			}
+		}
+	}
+	if (libObj.contains("rules"))
+	{
+		out->applyRules = true;
+		out->rules = rulesFromJsonV4(libObj);
+	}
+	return out;
+}
diff --git a/logic/minecraft/RawLibrary.h b/logic/minecraft/RawLibrary.h
new file mode 100644
index 000000000..46178d8e0
--- /dev/null
+++ b/logic/minecraft/RawLibrary.h
@@ -0,0 +1,47 @@
+#pragma once
+#include <QString>
+#include <QPair>
+#include <memory>
+
+#include "OneSixRule.h"
+
+class RawLibrary;
+typedef std::shared_ptr<RawLibrary> RawLibraryPtr;
+
+class RawLibrary
+{
+public: /* methods */
+	static RawLibraryPtr fromJson(const QJsonObject &libObj, const QString &filename);
+	
+public: /* data */
+	QString name;
+	QString url;
+	QString hint;
+	QString absoluteUrl;
+
+	bool applyExcludes = false;
+	QStringList excludes;
+
+	bool applyNatives = false;
+	QList<QPair<OpSys, QString>> natives;
+
+	bool applyRules = false;
+	QList<std::shared_ptr<Rule>> rules;
+
+	// user for '+' libraries
+	enum InsertType
+	{
+		Apply,
+		Append,
+		Prepend,
+		Replace
+	} insertType = Append;
+	QString insertData;
+	
+	// soft or hard dependency? hard means 'needs equal', soft means 'needs equal or newer'
+	enum DependType
+	{
+		Soft,
+		Hard
+	} dependType = Soft;
+};
diff --git a/logic/minecraft/OneSixVersionBuilder.cpp b/logic/minecraft/VersionBuilder.cpp
similarity index 90%
rename from logic/minecraft/OneSixVersionBuilder.cpp
rename to logic/minecraft/VersionBuilder.cpp
index da8f956c5..56eef4245 100644
--- a/logic/minecraft/OneSixVersionBuilder.cpp
+++ b/logic/minecraft/VersionBuilder.cpp
@@ -25,7 +25,7 @@
 #include <QDebug>
 #include <modutils.h>
 
-#include "logic/minecraft/OneSixVersionBuilder.h"
+#include "logic/minecraft/VersionBuilder.h"
 #include "logic/minecraft/VersionFinal.h"
 #include "logic/minecraft/OneSixRule.h"
 #include "logic/minecraft/VersionFile.h"
@@ -35,28 +35,28 @@
 
 #include "logger/QsLog.h"
 
-OneSixVersionBuilder::OneSixVersionBuilder()
+VersionBuilder::VersionBuilder()
 {
 }
 
-void OneSixVersionBuilder::build(VersionFinal *version, OneSixInstance *instance, const QStringList &external)
+void VersionBuilder::build(VersionFinal *version, OneSixInstance *instance, const QStringList &external)
 {
-	OneSixVersionBuilder builder;
+	VersionBuilder builder;
 	builder.m_version = version;
 	builder.m_instance = instance;
 	builder.buildInternal(external);
 }
 
-void OneSixVersionBuilder::readJsonAndApplyToVersion(VersionFinal *version,
+void VersionBuilder::readJsonAndApplyToVersion(VersionFinal *version,
 													 const QJsonObject &obj)
 {
-	OneSixVersionBuilder builder;
+	VersionBuilder builder;
 	builder.m_version = version;
 	builder.m_instance = 0;
 	builder.readJsonAndApply(obj);
 }
 
-void OneSixVersionBuilder::buildInternal(const QStringList &external)
+void VersionBuilder::buildInternal(const QStringList &external)
 {
 	m_version->versionFiles.clear();
 
@@ -139,7 +139,7 @@ void OneSixVersionBuilder::buildInternal(const QStringList &external)
 
 
 
-void OneSixVersionBuilder::readJsonAndApply(const QJsonObject &obj)
+void VersionBuilder::readJsonAndApply(const QJsonObject &obj)
 {
 	m_version->clear();
 
@@ -153,7 +153,7 @@ void OneSixVersionBuilder::readJsonAndApply(const QJsonObject &obj)
 	// version of MultiMC"));
 }
 
-VersionFilePtr OneSixVersionBuilder::parseJsonFile(const QFileInfo &fileInfo,
+VersionFilePtr VersionBuilder::parseJsonFile(const QFileInfo &fileInfo,
 												   const bool requireOrder, bool isFTB)
 {
 	QFile file(fileInfo.absoluteFilePath());
@@ -175,7 +175,7 @@ VersionFilePtr OneSixVersionBuilder::parseJsonFile(const QFileInfo &fileInfo,
 	// info.").arg(file.fileName());
 }
 
-QMap<QString, int> OneSixVersionBuilder::readOverrideOrders(OneSixInstance *instance)
+QMap<QString, int> VersionBuilder::readOverrideOrders(OneSixInstance *instance)
 {
 	QMap<QString, int> out;
 
@@ -225,7 +225,7 @@ QMap<QString, int> OneSixVersionBuilder::readOverrideOrders(OneSixInstance *inst
 	return out;
 }
 
-bool OneSixVersionBuilder::writeOverrideOrders(const QMap<QString, int> &order,
+bool VersionBuilder::writeOverrideOrders(const QMap<QString, int> &order,
 											   OneSixInstance *instance)
 {
 	QJsonObject obj;
diff --git a/logic/minecraft/OneSixVersionBuilder.h b/logic/minecraft/VersionBuilder.h
similarity index 96%
rename from logic/minecraft/OneSixVersionBuilder.h
rename to logic/minecraft/VersionBuilder.h
index 6646584ef..ac93ef118 100644
--- a/logic/minecraft/OneSixVersionBuilder.h
+++ b/logic/minecraft/VersionBuilder.h
@@ -24,9 +24,9 @@ class OneSixInstance;
 class QJsonObject;
 class QFileInfo;
 
-class OneSixVersionBuilder
+class VersionBuilder
 {
-	OneSixVersionBuilder();
+	VersionBuilder();
 public:
 	static void build(VersionFinal *version, OneSixInstance *instance, const QStringList &external);
 	static void readJsonAndApplyToVersion(VersionFinal *version, const QJsonObject &obj);
diff --git a/logic/minecraft/VersionFile.cpp b/logic/minecraft/VersionFile.cpp
index a011ce1a1..e1b03e6c2 100644
--- a/logic/minecraft/VersionFile.cpp
+++ b/logic/minecraft/VersionFile.cpp
@@ -7,111 +7,28 @@
 #include "logic/minecraft/VersionFile.h"
 #include "logic/minecraft/OneSixLibrary.h"
 #include "logic/minecraft/VersionFinal.h"
-#include "logic/MMCJson.h"
+#include "logic/minecraft/JarMod.h"
 
+#include "logic/MMCJson.h"
 using namespace MMCJson;
 
 #define CURRENT_MINIMUM_LAUNCHER_VERSION 14
 
-JarmodPtr Jarmod::fromJson(const QJsonObject &libObj, const QString &filename)
+int findLibrary(QList<OneSixLibraryPtr> haystack, const QString &needle)
 {
-	JarmodPtr out(new Jarmod());
-	if (!libObj.contains("name"))
+	int retval = -1;
+	for (int i = 0; i < haystack.size(); ++i)
 	{
-		throw JSONValidationError(filename +
-								  "contains a jarmod that doesn't have a 'name' field");
-	}
-	out->name = libObj.value("name").toString();
-
-	auto readString = [libObj, filename](const QString & key, QString & variable)
-	{
-		if (libObj.contains(key))
+		QString chunk = haystack.at(i)->rawName();
+		if (QRegExp(needle, Qt::CaseSensitive, QRegExp::WildcardUnix).indexIn(chunk) != -1)
 		{
-			QJsonValue val = libObj.value(key);
-			if (!val.isString())
-			{
-				QLOG_WARN() << key << "is not a string in" << filename << "(skipping)";
-			}
-			else
-			{
-				variable = val.toString();
-			}
-		}
-	};
-
-	readString("url", out->baseurl);
-	readString("MMC-absoluteUrl", out->absoluteUrl);
-	if(!out->baseurl.isEmpty() && out->absoluteUrl.isEmpty())
-	{
-		out->absoluteUrl = out->baseurl + out->name;
-	}
-	return out;
-
-}
-
-
-RawLibraryPtr RawLibrary::fromJson(const QJsonObject &libObj, const QString &filename)
-{
-	RawLibraryPtr out(new RawLibrary());
-	if (!libObj.contains("name"))
-	{
-		throw JSONValidationError(filename +
-								  "contains a library that doesn't have a 'name' field");
-	}
-	out->name = libObj.value("name").toString();
-
-	auto readString = [libObj, filename](const QString & key, QString & variable)
-	{
-		if (libObj.contains(key))
-		{
-			QJsonValue val = libObj.value(key);
-			if (!val.isString())
-			{
-				QLOG_WARN() << key << "is not a string in" << filename << "(skipping)";
-			}
-			else
-			{
-				variable = val.toString();
-			}
-		}
-	};
-
-	readString("url", out->url);
-	readString("MMC-hint", out->hint);
-	readString("MMC-absulute_url", out->absoluteUrl);
-	readString("MMC-absoluteUrl", out->absoluteUrl);
-	if (libObj.contains("extract"))
-	{
-		out->applyExcludes = true;
-		auto extractObj = ensureObject(libObj.value("extract"));
-		for (auto excludeVal : ensureArray(extractObj.value("exclude")))
-		{
-			out->excludes.append(ensureString(excludeVal));
+			// only one is allowed.
+			if(retval != -1)
+				return -1;
+			retval = i;
 		}
 	}
-	if (libObj.contains("natives"))
-	{
-		out->applyNatives = true;
-		QJsonObject nativesObj = ensureObject(libObj.value("natives"));
-		for (auto it = nativesObj.begin(); it != nativesObj.end(); ++it)
-		{
-			if (!it.value().isString())
-			{
-				QLOG_WARN() << filename << "contains an invalid native (skipping)";
-			}
-			OpSys opSys = OpSys_fromString(it.key());
-			if (opSys != Os_Other)
-			{
-				out->natives.append(qMakePair(opSys, it.value().toString()));
-			}
-		}
-	}
-	if (libObj.contains("rules"))
-	{
-		out->applyRules = true;
-		out->rules = rulesFromJsonV4(libObj);
-	}
-	return out;
+	return retval;
 }
 
 VersionFilePtr VersionFile::fromJson(const QJsonDocument &doc, const QString &filename,
@@ -351,23 +268,6 @@ OneSixLibraryPtr VersionFile::createLibrary(RawLibraryPtr lib)
 	return out;
 }
 
-int VersionFile::findLibrary(QList<OneSixLibraryPtr> haystack, const QString &needle)
-{
-	int retval = -1;
-	for (int i = 0; i < haystack.size(); ++i)
-	{
-		QString chunk = haystack.at(i)->rawName();
-		if (QRegExp(needle, Qt::CaseSensitive, QRegExp::WildcardUnix).indexIn(chunk) != -1)
-		{
-			// only one is allowed.
-			if(retval != -1)
-				return -1;
-			retval = i;
-		}
-	}
-	return retval;
-}
-
 bool VersionFile::isVanilla()
 {
 	return fileId == "org.multimc.version.json";
diff --git a/logic/minecraft/VersionFile.h b/logic/minecraft/VersionFile.h
index 8234445b6..82b169138 100644
--- a/logic/minecraft/VersionFile.h
+++ b/logic/minecraft/VersionFile.h
@@ -5,10 +5,14 @@
 #include <memory>
 #include "logic/minecraft/OpSys.h"
 #include "logic/minecraft/OneSixRule.h"
+#include "VersionPatch.h"
 #include "MMCError.h"
+#include "RawLibrary.h"
+#include "JarMod.h"
 
 class VersionFinal;
 
+
 class VersionBuildError : public MMCError
 {
 public:
@@ -46,66 +50,19 @@ public:
 	virtual ~MinecraftVersionMismatch() noexcept {}
 };
 
-struct RawLibrary;
-typedef std::shared_ptr<RawLibrary> RawLibraryPtr;
-struct RawLibrary
-{
-	QString name;
-	QString url;
-	QString hint;
-	QString absoluteUrl;
-	bool applyExcludes = false;
-	QStringList excludes;
-	bool applyNatives = false;
-	QList<QPair<OpSys, QString>> natives;
-	bool applyRules = false;
-	QList<std::shared_ptr<Rule>> rules;
-
-	// user for '+' libraries
-	enum InsertType
-	{
-		Apply,
-		Append,
-		Prepend,
-		Replace
-	};
-	InsertType insertType = Append;
-	QString insertData;
-	enum DependType
-	{
-		Soft,
-		Hard
-	};
-	DependType dependType = Soft;
-
-	static RawLibraryPtr fromJson(const QJsonObject &libObj, const QString &filename);
-};
-
-struct Jarmod;
-typedef std::shared_ptr<Jarmod> JarmodPtr;
-struct Jarmod
-{
-	QString name;
-	QString baseurl;
-	QString hint;
-	QString absoluteUrl;
-	
-	static JarmodPtr fromJson(const QJsonObject &libObj, const QString &filename);
-};
-
 struct VersionFile;
 typedef std::shared_ptr<VersionFile> VersionFilePtr;
-struct VersionFile
+class VersionFile : public VersionPatch
 {
 public: /* methods */
 	static VersionFilePtr fromJson(const QJsonDocument &doc, const QString &filename,
 								   const bool requireOrder, const bool isFTB = false);
 
 	static OneSixLibraryPtr createLibrary(RawLibraryPtr lib);
-	int findLibrary(QList<OneSixLibraryPtr> haystack, const QString &needle);
-	void applyTo(VersionFinal *version);
-	bool isVanilla();
-	bool hasJarMods();
+	virtual void applyTo(VersionFinal *version) override;
+	virtual bool isVanilla() override;
+	virtual bool hasJarMods() override;
+	
 public: /* data */
 	int order = 0;
 	QString name;
@@ -143,3 +100,5 @@ public: /* data */
 
 	QList<JarmodPtr> jarMods;
 };
+
+
diff --git a/logic/minecraft/VersionFinal.cpp b/logic/minecraft/VersionFinal.cpp
index fbf6a1609..07f58778c 100644
--- a/logic/minecraft/VersionFinal.cpp
+++ b/logic/minecraft/VersionFinal.cpp
@@ -19,7 +19,7 @@
 #include <pathutils.h>
 
 #include "logic/minecraft/VersionFinal.h"
-#include "logic/minecraft/OneSixVersionBuilder.h"
+#include "logic/minecraft/VersionBuilder.h"
 #include "logic/OneSixInstance.h"
 
 VersionFinal::VersionFinal(OneSixInstance *instance, QObject *parent)
@@ -31,7 +31,7 @@ VersionFinal::VersionFinal(OneSixInstance *instance, QObject *parent)
 void VersionFinal::reload(const QStringList &external)
 {
 	beginResetModel();
-	OneSixVersionBuilder::build(this, m_instance, external);
+	VersionBuilder::build(this, m_instance, external);
 	reapply(true);
 	endResetModel();
 }
@@ -116,7 +116,7 @@ QString VersionFinal::versionFileId(const int index) const
 	return versionFiles.at(index)->fileId;
 }
 
-VersionFilePtr VersionFinal::versionFile(const QString &id)
+VersionFilePtr VersionFinal::versionPatch(const QString &id)
 {
 	for (auto file : versionFiles)
 	{
@@ -135,7 +135,7 @@ bool VersionFinal::hasJarMods()
 
 bool VersionFinal::hasFtbPack()
 {
-	return versionFile("org.multimc.ftb.pack.json") != nullptr;
+	return versionPatch("org.multimc.ftb.pack.json") != nullptr;
 }
 
 bool VersionFinal::removeFtbPack()
@@ -216,7 +216,7 @@ std::shared_ptr<VersionFinal> VersionFinal::fromJson(const QJsonObject &obj)
 	std::shared_ptr<VersionFinal> version(new VersionFinal(0));
 	try
 	{
-		OneSixVersionBuilder::readJsonAndApplyToVersion(version.get(), obj);
+		VersionBuilder::readJsonAndApplyToVersion(version.get(), obj);
 	}
 	catch(MMCError & err)
 	{
@@ -299,7 +299,7 @@ QMap<QString, int> VersionFinal::getExistingOrder() const
 	}
 	// overriden
 	{
-		QMap<QString, int> overridenOrder = OneSixVersionBuilder::readOverrideOrders(m_instance);
+		QMap<QString, int> overridenOrder = VersionBuilder::readOverrideOrders(m_instance);
 		for (auto id : order.keys())
 		{
 			if (overridenOrder.contains(id))
@@ -348,7 +348,7 @@ void VersionFinal::move(const int index, const MoveDirection direction)
 	order[ourId] = theirIndex;
 	order[theirId] = index;
 
-	if (!OneSixVersionBuilder::writeOverrideOrders(order, m_instance))
+	if (!VersionBuilder::writeOverrideOrders(order, m_instance))
 	{
 		throw MMCError(tr("Couldn't save the new order"));
 	}
@@ -378,7 +378,7 @@ void VersionFinal::reapply(const bool alreadyReseting)
 	QList<VersionFilePtr> newVersionFiles;
 	for (auto order : orders)
 	{
-		auto file = versionFile(existingOrders.key(order));
+		auto file = versionPatch(existingOrders.key(order));
 		newVersionFiles.append(file);
 		file->applyTo(this);
 	}
diff --git a/logic/minecraft/VersionFinal.h b/logic/minecraft/VersionFinal.h
index ceb90f57c..7be981ed4 100644
--- a/logic/minecraft/VersionFinal.h
+++ b/logic/minecraft/VersionFinal.h
@@ -23,6 +23,7 @@
 
 #include "OneSixLibrary.h"
 #include "VersionFile.h"
+#include "JarMod.h"
 
 class OneSixInstance;
 
@@ -164,7 +165,7 @@ public:
 	// QList<Rule> rules;
 
 	QList<VersionFilePtr> versionFiles;
-	VersionFilePtr versionFile(const QString &id);
+	VersionFilePtr versionPatch(const QString &id);
 
 private:
 	OneSixInstance *m_instance;
diff --git a/logic/minecraft/VersionPatch.h b/logic/minecraft/VersionPatch.h
new file mode 100644
index 000000000..c22587874
--- /dev/null
+++ b/logic/minecraft/VersionPatch.h
@@ -0,0 +1,15 @@
+#pragma once
+
+#include <memory>
+
+class VersionFinal;
+class VersionPatch
+{
+public:
+	virtual ~VersionPatch(){};
+	virtual void applyTo(VersionFinal *version) = 0;
+	virtual bool isVanilla() = 0;
+	virtual bool hasJarMods() = 0;
+};
+
+typedef std::shared_ptr<VersionPatch> VersionPatchPtr;