diff --git a/InstructionSets/x86/Decoder.cpp b/InstructionSets/x86/Decoder.cpp
index 45dd5ef71..d4c910903 100644
--- a/InstructionSets/x86/Decoder.cpp
+++ b/InstructionSets/x86/Decoder.cpp
@@ -14,10 +14,8 @@
 
 using namespace InstructionSet::x86;
 
-// Only 8086 is suppoted for now.
-Decoder::Decoder(Model model) : model_(model) {}
-
-std::pair<int, InstructionSet::x86::Instruction> Decoder::decode(const uint8_t *source, size_t length) {
+template <Model model>
+std::pair<int, InstructionSet::x86::Instruction> Decoder<model>::decode(const uint8_t *source, size_t length) {
 	const uint8_t *const end = source + length;
 
 	// MARK: - Prefixes (if present) and the opcode.
@@ -115,7 +113,7 @@ std::pair<int, InstructionSet::x86::Instruction> Decoder::decode(const uint8_t *
 			// The 286 onwards have a further set of instructions
 			// prefixed with $0f.
 			case 0x0f:
-				if(model_ < Model::i80286) undefined();
+				if constexpr (model < Model::i80286) undefined();
 				phase_ = Phase::InstructionPageF;
 			break;
 
@@ -163,35 +161,35 @@ std::pair<int, InstructionSet::x86::Instruction> Decoder::decode(const uint8_t *
 #undef RegisterBlock
 
 			case 0x60:
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Complete(PUSHA, None, None, 2);
 			break;
 			case 0x61:
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Complete(POPA, None, None, 2);
 			break;
 			case 0x62:
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				MemRegReg(BOUND, Reg_MemReg, 2);
 			break;
 			case 0x63:
-				if(model_ < Model::i80286) undefined();
+				if constexpr (model < Model::i80286) undefined();
 				MemRegReg(ARPL, MemReg_Reg, 2);
 			break;
 			case 0x6c:	// INSB
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Complete(INS, None, None, 1);
 			break;
 			case 0x6d:	// INSW
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Complete(INS, None, None, 2);
 			break;
 			case 0x6e:	// OUTSB
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Complete(OUTS, None, None, 1);
 			break;
 			case 0x6f:	// OUTSW
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Complete(OUTS, None, None, 2);
 			break;
 
@@ -291,11 +289,11 @@ std::pair<int, InstructionSet::x86::Instruction> Decoder::decode(const uint8_t *
 			case 0xc7: MemRegReg(MOV, MemRegMOV, 2);	break;
 
 			case 0xc8:
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Displacement16Operand8(ENTER);
 			break;
 			case 0xc9:
-				if(model_ < Model::i80186) undefined();
+				if constexpr (model < Model::i80186) undefined();
 				Complete(LEAVE, None, None, 0);
 			break;
 
@@ -392,7 +390,7 @@ std::pair<int, InstructionSet::x86::Instruction> Decoder::decode(const uint8_t *
 			case 0x02:	MemRegReg(LAR, Reg_MemReg, 2);				break;
 			case 0x03:	MemRegReg(LSL, Reg_MemReg, 2);				break;
 			case 0x05:
-				if(model_ != Model::i80286) undefined();
+				if constexpr (model != Model::i80286) undefined();
 				Complete(LOADALL, None, None, 0);
 			break;
 			case 0x06:	Complete(CLTS, None, None, 1);				break;
@@ -711,3 +709,9 @@ std::pair<int, InstructionSet::x86::Instruction> Decoder::decode(const uint8_t *
 	// i.e. not done yet.
 	return std::make_pair(0, Instruction());
 }
+
+// Ensure all possible decoders are built.
+template class InstructionSet::x86::Decoder<InstructionSet::x86::Model::i8086>;
+template class InstructionSet::x86::Decoder<InstructionSet::x86::Model::i80186>;
+template class InstructionSet::x86::Decoder<InstructionSet::x86::Model::i80286>;
+template class InstructionSet::x86::Decoder<InstructionSet::x86::Model::i80386>;
diff --git a/InstructionSets/x86/Decoder.hpp b/InstructionSets/x86/Decoder.hpp
index e2c68a907..4213c4fd5 100644
--- a/InstructionSets/x86/Decoder.hpp
+++ b/InstructionSets/x86/Decoder.hpp
@@ -29,10 +29,8 @@ enum class Model {
 
 	This is an experimental implementation; it has not yet undergone significant testing.
 */
-class Decoder {
+template <Model> class Decoder {
 	public:
-		Decoder(Model model);
-
 		/*!
 			@returns an @c Instruction plus a size; a positive size to indicate successful decoding; a
 				negative size specifies the [negatived] number of further bytes the caller should ideally
@@ -43,8 +41,6 @@ class Decoder {
 		std::pair<int, Instruction> decode(const uint8_t *source, size_t length);
 
 	private:
-		const Model model_;
-
 		enum class Phase {
 			/// Captures all prefixes and continues until an instruction byte is encountered.
 			Instruction,
diff --git a/OSBindings/Mac/Clock SignalTests/x86DecoderTests.mm b/OSBindings/Mac/Clock SignalTests/x86DecoderTests.mm
index 51617d7b4..9c2fd60d2 100644
--- a/OSBindings/Mac/Clock SignalTests/x86DecoderTests.mm	
+++ b/OSBindings/Mac/Clock SignalTests/x86DecoderTests.mm	
@@ -105,7 +105,7 @@ namespace {
 
 - (void)decode:(const std::initializer_list<uint8_t> &)stream {
 	// Decode by offering up all data at once.
-	InstructionSet::x86::Decoder decoder(InstructionSet::x86::Model::i8086);
+	InstructionSet::x86::Decoder<InstructionSet::x86::Model::i8086> decoder;
 	instructions.clear();
 	const uint8_t *byte = stream.begin();
 	while(byte != stream.end()) {
@@ -117,7 +117,7 @@ namespace {
 
 	// Grab a byte-at-a-time decoding and check that it matches the previous.
 	{
-		InstructionSet::x86::Decoder decoder(InstructionSet::x86::Model::i8086);
+		InstructionSet::x86::Decoder<InstructionSet::x86::Model::i8086> decoder;
 
 		auto previous_instruction = instructions.begin();
 		for(auto item: stream) {