diff --git a/include/td/game/GameHistory.h b/include/td/game/GameHistory.h
index 9407c61..c5c4f61 100644
--- a/include/td/game/GameHistory.h
+++ b/include/td/game/GameHistory.h
@@ -2,6 +2,7 @@
 
 #include <optional>
 #include <td/protocol/command/Commands.h>
+#include <td/protocol/packet/Packets.h>
 
 namespace td {
 namespace game {
@@ -10,47 +11,26 @@ class GameHistory {
   private:
 	using HistorySizeType = std::uint16_t;
 
-	std::vector<std::optional<protocol::LockStep>> m_History {std::numeric_limits<HistorySizeType>::max()};
+	std::vector<std::optional<protocol::LockStep>> m_History;
 	
-	HistorySizeType m_Cursor = 0;
+	HistorySizeType m_Cursor;
 
   public:
-	GameHistory(){}
+	GameHistory();
 
-	void SetLockStep(HistorySizeType a_Index, protocol::LockStep&& a_LockStep) {
-		m_History[a_Index] = std::move(a_LockStep);
-	}
+	void SetLockStep(HistorySizeType a_Index, protocol::LockStep&& a_LockStep);
 
-	const protocol::LockStep& GetLockStep(HistorySizeType a_Index) const {
-		return *m_History[a_Index];
-	}
+	const protocol::LockStep& GetLockStep(HistorySizeType a_Index) const;
 
-	bool HasLockStep(HistorySizeType a_Index) const {
-		return m_History[a_Index].has_value();
-	}
+	bool HasLockStep(HistorySizeType a_Index) const;
 
-	const protocol::LockStep& GetNextStep() {
-		return GetLockStep(m_Cursor++);
-	}
+	const protocol::LockStep& GetNextStep();
 
-	bool HasNextStep() const {
-		return HasLockStep(m_Cursor);
-	}
+	bool HasNextStep() const;
 
-	void FromPacket(td::protocol::pdata::LockSteps&& a_Steps) {
-		for (int i = 0; i < LOCKSTEP_BUFFER_SIZE; i++) {
-			protocol::LockStep& step = a_Steps.m_LockSteps[i];
-			SetLockStep(i + a_Steps.m_FirstFrameNumber, std::move(step));
-		}
-	}
+	void FromPacket(td::protocol::pdata::LockSteps&& a_Steps);
 
-	td::protocol::packets::LockSteps ToPacket(HistorySizeType a_StartIndex) {
-		std::array<protocol::LockStep, LOCKSTEP_BUFFER_SIZE> steps;
-		for (int i = 0; i < LOCKSTEP_BUFFER_SIZE; i++) {
-			steps[i] = GetLockStep(a_StartIndex + i);
-		}
-		return {{a_StartIndex, std::move(steps)}};
-	}
+	td::protocol::packets::LockSteps ToPacket(HistorySizeType a_StartIndex);
 };
 
 }  // namespace game
diff --git a/src/td/game/GameHistory.cpp b/src/td/game/GameHistory.cpp
new file mode 100644
index 0000000..2ed127e
--- /dev/null
+++ b/src/td/game/GameHistory.cpp
@@ -0,0 +1,44 @@
+#include <td/game/GameHistory.h>
+
+namespace td {
+namespace game {
+
+GameHistory::GameHistory() : m_History(std::numeric_limits<HistorySizeType>::max()), m_Cursor(0) {}
+
+void GameHistory::SetLockStep(HistorySizeType a_Index, protocol::LockStep&& a_LockStep) {
+	m_History[a_Index] = std::move(a_LockStep);
+}
+
+const protocol::LockStep& GameHistory::GetLockStep(HistorySizeType a_Index) const {
+	return *m_History[a_Index];
+}
+
+bool GameHistory::HasLockStep(HistorySizeType a_Index) const {
+	return m_History[a_Index].has_value();
+}
+
+const protocol::LockStep& GameHistory::GetNextStep() {
+	return GetLockStep(m_Cursor++);
+}
+
+bool GameHistory::HasNextStep() const {
+	return HasLockStep(m_Cursor);
+}
+
+void GameHistory::FromPacket(td::protocol::pdata::LockSteps&& a_Steps) {
+	for (int i = 0; i < LOCKSTEP_BUFFER_SIZE; i++) {
+		protocol::LockStep& step = a_Steps.m_LockSteps[i];
+		SetLockStep(i + a_Steps.m_FirstFrameNumber, std::move(step));
+	}
+}
+
+td::protocol::packets::LockSteps GameHistory::ToPacket(HistorySizeType a_StartIndex) {
+	std::array<protocol::LockStep, LOCKSTEP_BUFFER_SIZE> steps;
+	for (int i = 0; i < LOCKSTEP_BUFFER_SIZE; i++) {
+		steps[i] = GetLockStep(a_StartIndex + i);
+	}
+	return {{a_StartIndex, std::move(steps)}};
+}
+
+}  // namespace game
+}  // namespace td