diff --git a/source/interpreter.c b/source/interpreter.c
index 28caef4..059c581 100644
--- a/source/interpreter.c
+++ b/source/interpreter.c
@@ -54,20 +54,20 @@ static char* readString(unsigned char* tb, int* count) {
 
 static void consumeByte(unsigned char byte, unsigned char* tb, int* count) {
 	if (byte != tb[*count]) {
-		printf("Failed to consume the correct byte");
+		printf("Failed to consume the correct byte\n");
 	}
 	*count += 1;
 }
 
 static void consumeShort(unsigned short bytes, unsigned char* tb, int* count) {
 	if (bytes != *(unsigned short*)(tb + *count)) {
-		printf("Failed to consume the correct bytes");
+		printf("Failed to consume the correct bytes\n");
 	}
 	*count += 2;
 }
 
 //each available statement
-static void execPrint(Interpreter* interpreter) {
+static bool execPrint(Interpreter* interpreter) {
 	//print what is on top of the stack, then pop it
 	Literal lit = popLiteralArray(&interpreter->stack);
 
@@ -75,9 +75,11 @@ static void execPrint(Interpreter* interpreter) {
 	printf("\n");
 
 	freeLiteral(lit);
+
+	return true;
 }
 
-static void execPushLiteral(Interpreter* interpreter, bool lng) {
+static bool execPushLiteral(Interpreter* interpreter, bool lng) {
 	//read the index in the cache
 	int index = 0;
 
@@ -90,9 +92,11 @@ static void execPushLiteral(Interpreter* interpreter, bool lng) {
 
 	//push from cache to stack
 	pushLiteralArray(&interpreter->stack, interpreter->literalCache.literals[index]);
+
+	return true;
 }
 
-static void execNegate(Interpreter* interpreter) {
+static bool execNegate(Interpreter* interpreter) {
 	//negate the top literal on the stack
 	Literal lit = popLiteralArray(&interpreter->stack);
 
@@ -106,9 +110,81 @@ static void execNegate(Interpreter* interpreter) {
 		printf("[internal] The interpreter can't negate that literal: ");
 		printLiteral(lit);
 		printf("\n");
+		return false;
 	}
 
 	pushLiteralArray(&interpreter->stack, lit);
+	return true;
+}
+
+static bool execArithmetic(Interpreter* interpreter, Opcode opcode) {
+	Literal rhs = popLiteralArray(&interpreter->stack);
+	Literal lhs = popLiteralArray(&interpreter->stack);
+
+	//type coersion
+	if (IS_FLOAT(lhs) && IS_INTEGER(rhs)) {
+		rhs = TO_FLOAT_LITERAL(AS_INTEGER(rhs));
+	}
+
+	if (IS_INTEGER(lhs) && IS_FLOAT(rhs)) {
+		lhs = TO_FLOAT_LITERAL(AS_INTEGER(lhs));
+	}
+
+	//maths based on types
+	if(IS_INTEGER(lhs) && IS_INTEGER(rhs)) {
+		switch(opcode) {
+			case OP_ADDITION:
+				pushLiteralArray(&interpreter->stack, TO_INTEGER_LITERAL( AS_INTEGER(lhs) + AS_INTEGER(rhs) ));
+				return true;
+
+			case OP_SUBTRACTION:
+				pushLiteralArray(&interpreter->stack, TO_INTEGER_LITERAL( AS_INTEGER(lhs) - AS_INTEGER(rhs) ));
+				return true;
+
+			case OP_MULTIPLICATION:
+				pushLiteralArray(&interpreter->stack, TO_INTEGER_LITERAL( AS_INTEGER(lhs) * AS_INTEGER(rhs) ));
+				return true;
+
+			case OP_DIVISION:
+				pushLiteralArray(&interpreter->stack, TO_INTEGER_LITERAL( AS_INTEGER(lhs) / AS_INTEGER(rhs) ));
+				return true;
+
+			case OP_MODULO:
+				pushLiteralArray(&interpreter->stack, TO_INTEGER_LITERAL( AS_INTEGER(lhs) % AS_INTEGER(rhs) ));
+				return true;
+
+		}
+	}
+
+	//catch bad modulo
+	if (opcode == OP_MODULO) {
+		printf("Bad arithmetic argument (modulo on floats not allowed)");
+		return false;
+	}
+
+	if(IS_FLOAT(lhs) && IS_FLOAT(rhs)) {
+		switch(opcode) {
+			case OP_ADDITION:
+				pushLiteralArray(&interpreter->stack, TO_FLOAT_LITERAL( AS_FLOAT(lhs) + AS_FLOAT(rhs) ));
+				return true;
+
+			case OP_SUBTRACTION:
+				pushLiteralArray(&interpreter->stack, TO_FLOAT_LITERAL( AS_FLOAT(lhs) - AS_FLOAT(rhs) ));
+				return true;
+
+			case OP_MULTIPLICATION:
+				pushLiteralArray(&interpreter->stack, TO_FLOAT_LITERAL( AS_FLOAT(lhs) * AS_FLOAT(rhs) ));
+				return true;
+
+			case OP_DIVISION:
+				pushLiteralArray(&interpreter->stack, TO_FLOAT_LITERAL( AS_FLOAT(lhs) / AS_FLOAT(rhs) ));
+				return true;
+		}
+	}
+
+	//wrong types
+	printf("Bad arithmetic argument");
+	return false;
 }
 
 //the heart of toy
@@ -118,16 +194,32 @@ static void execInterpreter(Interpreter* interpreter) {
 	while(opcode != OP_EOF && opcode != OP_SECTION_END) {
 		switch(opcode) {
 			case OP_PRINT:
-				execPrint(interpreter);
+				if (!execPrint(interpreter)) {
+					return;
+				}
 			break;
 
 			case OP_LITERAL:
 			case OP_LITERAL_LONG:
-				execPushLiteral(interpreter, opcode == OP_LITERAL_LONG);
+				if (!execPushLiteral(interpreter, opcode == OP_LITERAL_LONG)) {
+					return;
+				}
 			break;
 
 			case OP_NEGATE:
-				execNegate(interpreter);
+				if (!execNegate(interpreter)) {
+					return;
+				}
+			break;
+
+			case OP_ADDITION:
+			case OP_SUBTRACTION:
+			case OP_MULTIPLICATION:
+			case OP_DIVISION:
+			case OP_MODULO:
+				if (!execArithmetic(interpreter, opcode)) {
+					return;
+				}
 			break;
 
 			default:
diff --git a/source/node.c b/source/node.c
index 145a505..58692ed 100644
--- a/source/node.c
+++ b/source/node.c
@@ -40,6 +40,17 @@ void emitNodeUnary(Node** nodeHandle, Opcode opcode) {
 	(*nodeHandle)->unary.child = NULL;
 }
 
+void emitNodeBinary(Node** nodeHandle, Node* rhs, Opcode opcode) {
+	Node* tmp = ALLOCATE(Node, 1);
+
+	tmp->type = NODE_BINARY;
+	tmp->binary.opcode = opcode;
+	tmp->binary.left = *nodeHandle;
+	tmp->binary.right = rhs;
+
+	*nodeHandle = tmp;
+}
+
 void printNode(Node* node) {
 	switch(node->type) {
 		case NODE_LITERAL:
@@ -53,10 +64,11 @@ void printNode(Node* node) {
 			break;
 
 		case NODE_BINARY:
-			printf("binary left:");
+			printf("binary-left:");
 			printNode(node->binary.left);
-			printf("binary right:");
+			printf("binary-right:");
 			printNode(node->binary.right);
+			printf(";");
 			break;
 	}
 }
\ No newline at end of file
diff --git a/source/node.h b/source/node.h
index c84a894..fd90115 100644
--- a/source/node.h
+++ b/source/node.h
@@ -42,6 +42,7 @@ union _node {
 void freeNode(Node* node);
 void emitNodeLiteral(Node** nodeHandle, Literal literal);
 void emitNodeUnary(Node** nodeHandle, Opcode opcode);
+void emitNodeBinary(Node** nodeHandle, Node* rhs, Opcode opcode);
 
 void printNode(Node* node);
 
diff --git a/source/opcodes.h b/source/opcodes.h
index 4272183..2542fee 100644
--- a/source/opcodes.h
+++ b/source/opcodes.h
@@ -12,6 +12,11 @@ typedef enum Opcode {
 
 	//operators
 	OP_NEGATE,
+	OP_ADDITION,
+	OP_SUBTRACTION,
+	OP_MULTIPLICATION,
+	OP_DIVISION,
+	OP_MODULO,
 
 	//meta
 	OP_SECTION_END,
diff --git a/source/parser.c b/source/parser.c
index 0e6bbf4..09147bb 100644
--- a/source/parser.c
+++ b/source/parser.c
@@ -4,6 +4,7 @@
 
 #include "memory.h"
 #include "literal.h"
+#include "opcodes.h"
 
 #include <stdio.h>
 
@@ -98,7 +99,7 @@ typedef enum {
 	PREC_PRIMARY,
 } PrecedenceRule;
 
-typedef void (*ParseFn)(Parser* parser, Node** nodeHandle, bool canBeAssigned);
+typedef Opcode (*ParseFn)(Parser* parser, Node** nodeHandle, bool canBeAssigned);
 
 typedef struct {
 	ParseFn prefix;
@@ -112,25 +113,58 @@ ParseRule parseRules[];
 static void parsePrecedence(Parser* parser, Node** nodeHandle, PrecedenceRule rule);
 
 //the expression rules
-static void string(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
+static Opcode string(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
 	//handle strings
 	switch(parser->previous.type) {
 		case TOKEN_LITERAL_STRING:
 			emitNodeLiteral(nodeHandle, TO_STRING_LITERAL(copyString(parser->previous.lexeme, parser->previous.length)));
-		break;
+			return OP_EOF;
 
 		//TODO: interpolated strings
 
 		default:
 			error(parser, parser->previous, "Unexpected token passed to string precedence rule");
+			return OP_EOF;
 	}
 }
 
-static void binary(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
-	//TODO
+static Opcode binary(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
+	advance(parser);
+
+	//binary() is an infix rule - so only get the RHS of the operator
+	switch(parser->previous.type) {
+		case TOKEN_PLUS: {
+			parsePrecedence(parser, nodeHandle, PREC_TERM);
+			return OP_ADDITION;
+		}
+
+		case TOKEN_MINUS: {
+			parsePrecedence(parser, nodeHandle, PREC_TERM);
+			return OP_SUBTRACTION;
+		}
+
+		case TOKEN_MULTIPLY: {
+			parsePrecedence(parser, nodeHandle, PREC_FACTOR);
+			return OP_MULTIPLICATION;
+		}
+
+		case TOKEN_DIVIDE: {
+			parsePrecedence(parser, nodeHandle, PREC_FACTOR);
+			return OP_DIVISION;
+		}
+
+		case TOKEN_MODULO: {
+			parsePrecedence(parser, nodeHandle, PREC_FACTOR);
+			return OP_MODULO;
+		}
+
+	default:
+		error(parser, parser->previous, "Unexpected token passed to binary precedence rule");
+		return OP_EOF;
+	}
 }
 
-static void unary(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
+static Opcode unary(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
 	switch(parser->previous.type) {
 		case TOKEN_MINUS: {
 			//temp handle to potentially negate values
@@ -153,7 +187,7 @@ static void unary(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
 				tmpNode->atomic.literal = lit;
 				*nodeHandle = tmpNode;
 
-				break;
+				return OP_EOF;
 			}
 
 			//process the literal without optimizations
@@ -161,48 +195,50 @@ static void unary(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
 				emitNodeUnary(nodeHandle, OP_NEGATE);
 				nodeHandle = &((*nodeHandle)->unary.child); //re-align after append
 				(*nodeHandle) = tmpNode; //set negate's child to the literal
-				break;
+				return OP_EOF;
 			}
 
 			error(parser, parser->previous, "Unexpected token passed to unary minus precedence rule");
+			return OP_EOF;
 		}
-		break;
 
 		default:
 			error(parser, parser->previous, "Unexpected token passed to unary precedence rule");
+			return OP_EOF;
 	}
 }
 
-static void atomic(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
+static Opcode atomic(Parser* parser, Node** nodeHandle, bool canBeAssigned) {
 	switch(parser->previous.type) {
 		case TOKEN_NULL:
 			emitNodeLiteral(nodeHandle, TO_NULL_LITERAL);
-		break;
+			return OP_EOF;
 
 		case TOKEN_LITERAL_TRUE:
 			emitNodeLiteral(nodeHandle, TO_BOOLEAN_LITERAL(true));
-		break;
+			return OP_EOF;
 
 		case TOKEN_LITERAL_FALSE:
 			emitNodeLiteral(nodeHandle, TO_BOOLEAN_LITERAL(false));
-		break;
+			return OP_EOF;
 
 		case TOKEN_LITERAL_INTEGER: {
 			int value = 0;
 			sscanf(parser->previous.lexeme, "%d", &value);
 			emitNodeLiteral(nodeHandle, TO_INTEGER_LITERAL(value));
+			return OP_EOF;
 		}
-		break;
 
 		case TOKEN_LITERAL_FLOAT: {
 			float value = 0;
 			sscanf(parser->previous.lexeme, "%f", &value);
 			emitNodeLiteral(nodeHandle, TO_FLOAT_LITERAL(value));
+			return OP_EOF;
 		}
-		break;
 
 		default:
 			error(parser, parser->previous, "Unexpected token passed to atomic precedence rule");
+			return OP_EOF;
 	}
 }
 
@@ -249,11 +285,11 @@ ParseRule parseRules[] = { //must match the token types
 	{string, NULL, PREC_PRIMARY},// TOKEN_LITERAL_STRING,
 
 	//math operators
-	{NULL, NULL, PREC_NONE},// TOKEN_PLUS,
-	{unary, NULL, PREC_UNARY},// TOKEN_MINUS,
-	{NULL, NULL, PREC_NONE},// TOKEN_MULTIPLY,
-	{NULL, NULL, PREC_NONE},// TOKEN_DIVIDE,
-	{NULL, NULL, PREC_NONE},// TOKEN_MODULO,
+	{NULL, binary, PREC_TERM},// TOKEN_PLUS,
+	{unary, binary, PREC_TERM},// TOKEN_MINUS,
+	{NULL, binary, PREC_TERM},// TOKEN_MULTIPLY,
+	{NULL, binary, PREC_TERM},// TOKEN_DIVIDE,
+	{NULL, binary, PREC_TERM},// TOKEN_MODULO,
 	{NULL, NULL, PREC_NONE},// TOKEN_PLUS_ASSIGN,
 	{NULL, NULL, PREC_NONE},// TOKEN_MINUS_ASSIGN,
 	{NULL, NULL, PREC_NONE},// TOKEN_MULTIPLY_ASSIGN,
@@ -298,6 +334,114 @@ ParseRule* getRule(TokenType type) {
 	return &parseRules[type];
 }
 
+static bool calcStaticBinaryArithmetic(Node** nodeHandle) {
+	switch((*nodeHandle)->binary.opcode) {
+		case OP_ADDITION:
+		case OP_SUBTRACTION:
+		case OP_MULTIPLICATION:
+		case OP_DIVISION:
+		case OP_MODULO:
+			break;
+
+		default:
+			return true;
+	}
+
+	//recurse to the left and right
+	if ((*nodeHandle)->binary.left->type == NODE_BINARY) {
+		calcStaticBinaryArithmetic(&(*nodeHandle)->binary.left);
+	}
+
+	if ((*nodeHandle)->binary.right->type == NODE_BINARY) {
+		calcStaticBinaryArithmetic(&(*nodeHandle)->binary.right);
+	}
+
+	//make sure left and right are both literals
+	if (!((*nodeHandle)->binary.left->type == NODE_LITERAL && (*nodeHandle)->binary.right->type == NODE_LITERAL)) {
+		return true;
+	}
+
+	//evaluate
+	Literal lhs = (*nodeHandle)->binary.left->atomic.literal;
+	Literal rhs = (*nodeHandle)->binary.right->atomic.literal;
+	Literal result = TO_NULL_LITERAL;
+
+	//type coersion
+	if (IS_FLOAT(lhs) && IS_INTEGER(rhs)) {
+		rhs = TO_FLOAT_LITERAL(AS_INTEGER(rhs));
+	}
+
+	if (IS_INTEGER(lhs) && IS_FLOAT(rhs)) {
+		lhs = TO_FLOAT_LITERAL(AS_INTEGER(lhs));
+	}
+
+	//maths based on types
+	if(IS_INTEGER(lhs) && IS_INTEGER(rhs)) {
+		switch((*nodeHandle)->binary.opcode) {
+			case OP_ADDITION:
+				result = TO_INTEGER_LITERAL( AS_INTEGER(lhs) + AS_INTEGER(rhs) );
+			break;
+
+			case OP_SUBTRACTION:
+				result = TO_INTEGER_LITERAL( AS_INTEGER(lhs) - AS_INTEGER(rhs) );
+			break;
+
+			case OP_MULTIPLICATION:
+				result = TO_INTEGER_LITERAL( AS_INTEGER(lhs) * AS_INTEGER(rhs) );
+			break;
+
+			case OP_DIVISION:
+				result = TO_INTEGER_LITERAL( AS_INTEGER(lhs) / AS_INTEGER(rhs) );
+			break;
+
+			case OP_MODULO:
+				result = TO_INTEGER_LITERAL( AS_INTEGER(lhs) % AS_INTEGER(rhs) );
+			break;
+		}
+	}
+
+	//catch bad modulo
+	if ((IS_FLOAT(lhs) || IS_FLOAT(rhs)) && (*nodeHandle)->binary.opcode == OP_MODULO) {
+		printf("Bad arithmetic argument (modulo on floats not allowed)");
+		return false;
+	}
+
+	if(IS_FLOAT(lhs) && IS_FLOAT(rhs)) {
+		switch((*nodeHandle)->binary.opcode) {
+			case OP_ADDITION:
+				printf("binary foobar");
+				result = TO_FLOAT_LITERAL( AS_FLOAT(lhs) + AS_FLOAT(rhs) );
+			break;
+
+			case OP_SUBTRACTION:
+				result = TO_FLOAT_LITERAL( AS_FLOAT(lhs) - AS_FLOAT(rhs) );
+			break;
+
+			case OP_MULTIPLICATION:
+				result = TO_FLOAT_LITERAL( AS_FLOAT(lhs) * AS_FLOAT(rhs) );
+			break;
+
+			case OP_DIVISION:
+				result = TO_FLOAT_LITERAL( AS_FLOAT(lhs) / AS_FLOAT(rhs) );
+			break;
+		}
+	}
+
+	//nothing can be done to optimize
+	if (IS_NULL(result)) {
+		return true;
+	}
+
+	//optimize by converting this node into a literal
+	freeNode((*nodeHandle)->binary.left);
+	freeNode((*nodeHandle)->binary.right);
+
+	(*nodeHandle)->type = NODE_LITERAL;
+	(*nodeHandle)->atomic.literal = result;
+
+	return true;
+}
+
 static void parsePrecedence(Parser* parser, Node** nodeHandle, PrecedenceRule rule) {
 	//every expression has a prefix rule
 	advance(parser);
@@ -320,7 +464,13 @@ static void parsePrecedence(Parser* parser, Node** nodeHandle, PrecedenceRule ru
 			return;
 		}
 
-		infixRule(parser, nodeHandle, canBeAssigned); //NOTE: infix rule must advance the parser
+		Node* rhsNode = NULL;
+		const Opcode opcode = infixRule(parser, &rhsNode, canBeAssigned); //NOTE: infix rule must advance the parser
+		emitNodeBinary(nodeHandle, rhsNode, opcode);
+
+		if (command.optimize >= 1 && !calcStaticBinaryArithmetic(nodeHandle)) {
+			return;
+		}
 	}
 
 	//if your precedence is below "assignment"
diff --git a/source/repl_main.c b/source/repl_main.c
index 7fff761..e558281 100644
--- a/source/repl_main.c
+++ b/source/repl_main.c
@@ -91,7 +91,7 @@ void repl() {
 	Interpreter interpreter; //persist the interpreter for the scopes
 
 	for(;;) {
-		printf(">");
+		printf("> ");
 		fgets(input, size, stdin);
 
 		//setup this iteration