diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4460ae5..1f00baf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -74,18 +74,18 @@ add_library(lib${PROJECT_NAME} SHARED
         src/assembler/as_exceptions.hh
         src/instructions/instruction.hh
         src/instructions/instruction.cc
-        #src/vm/code.cc
-        #src/vm/code.hh
-        #src/vm/value.cc
-        #src/vm/value.hh
-        #src/vm/stack.cc
-        #src/vm/stack.hh
-        #src/vm/vm_exceptions.hh
-        #src/vm/vm.cc
-        #src/vm/vm.hh
-        #src/vm/expr.cc
-        #src/vm/expr.hh
-        #src/vm/location.hh
+        src/vm/code.cc
+        src/vm/code.hh
+        src/vm/value.cc
+        src/vm/value.hh
+        src/vm/stack.cc
+        src/vm/stack.hh
+        src/vm/vm_exceptions.hh
+        src/vm/vm.cc
+        src/vm/vm.hh
+        src/vm/expr.cc
+        src/vm/expr.hh
+        src/vm/location.hh
 )
 
 target_compile_options(lib${PROJECT_NAME} PRIVATE ${warnings})
diff --git a/src/vm/expr.cc b/src/vm/expr.cc
index 67123ea..bcc00a3 100644
--- a/src/vm/expr.cc
+++ b/src/vm/expr.cc
@@ -35,7 +35,7 @@ static int init_ = []() {
     BIN_OP(Sum, Integer, Float)   { return Value::createFloat((float) a.as_integer() + b.as_float()); };
     BIN_OP(Sum, Float, Integer)   { return Value::createFloat(a.as_float() + (float) b.as_integer()); };
     BIN_OP(Sum, Float, Float)     { return Value::createFloat(a.as_float() + b.as_float()); };
-    BIN_OP(Sum, String, String)   { return Value::createString(a.as_string() + b.as_string()); };
+    BIN_OP(Sum, String, String)   { return Value::createString(std::string(a.as_string_ptr()) + std::string(b.as_string_ptr())); };
 
     BIN_OP(Subtraction, Integer, Integer) { return Value::createInteger(a.as_integer() - b.as_integer()); };
     BIN_OP(Subtraction, Integer, Float)   { return Value::createFloat((float) a.as_integer() - b.as_float()); };
@@ -61,13 +61,13 @@ static int init_ = []() {
     BIN_OP(Equality, Integer, Float)   { return Value::createIntegerFromBool(std::abs((float) a.as_integer() - b.as_float()) < FLOAT_EPSILON); };
     BIN_OP(Equality, Float, Integer)   { return Value::createIntegerFromBool(std::abs(a.as_float() - (float) b.as_integer()) < FLOAT_EPSILON); };
     BIN_OP(Equality, Float, Float)     { return Value::createIntegerFromBool(std::abs(a.as_float() - b.as_float()) < FLOAT_EPSILON); };
-    BIN_OP(Equality, String, String)   { return Value::createIntegerFromBool(a.as_string() == b.as_string()); };
+    BIN_OP(Equality, String, String)   { return Value::createIntegerFromBool(strcmp(a.as_string_ptr(), b.as_string_ptr()) == 0); };
 
     BIN_OP(Inequality, Integer, Integer) { return Value::createIntegerFromBool(a.as_integer() != b.as_integer()); };
     BIN_OP(Inequality, Integer, Float)   { return Value::createIntegerFromBool(std::abs((float) a.as_integer() - b.as_float()) >= FLOAT_EPSILON); };
     BIN_OP(Inequality, Float, Integer)   { return Value::createIntegerFromBool(std::abs(a.as_float() - (float) b.as_integer()) >= FLOAT_EPSILON); };
     BIN_OP(Inequality, Float, Float)     { return Value::createIntegerFromBool(std::abs(a.as_float() - b.as_float()) >= FLOAT_EPSILON); };
-    BIN_OP(Inequality, String, String)   { return Value::createIntegerFromBool(a.as_string() != b.as_string()); };
+    BIN_OP(Inequality, String, String)   { return Value::createIntegerFromBool(strcmp(a.as_string_ptr(), b.as_string_ptr()) != 0); };
 
     BIN_OP(LessThan, Integer, Integer) { return Value::createIntegerFromBool(a.as_integer() < b.as_integer()); };
     BIN_OP(LessThan, Integer, Float)   { return Value::createIntegerFromBool((float) a.as_integer() < b.as_float()); };
diff --git a/src/vm/tests.cc b/src/vm/tests.cc
index 23ed175..d7d1417 100644
--- a/src/vm/tests.cc
+++ b/src/vm/tests.cc
@@ -110,7 +110,7 @@ TEST(VM, StackOperations)
     ASSERT_FLOAT_EQ(run("pushi 5000").to_float(-1), 5000.f);
     ASSERT_FLOAT_EQ(run("pushc 0").to_float(-1), 3.14f);
     ASSERT_EQ(run("pushc 0").to_integer(-1), 3);
-    ASSERT_EQ(run("pushc 1").to_string(-1), "Hello world");
+    EXPECT_STREQ(run("pushc 1").to_string_ptr(-1), "Hello world");
     ASSERT_TRUE(run("pushf 0").is_function(-1));
     ASSERT_EQ(run("pushi 2\n pushi 3\n pop").to_integer(-1), 2);
 }
@@ -233,7 +233,7 @@ TEST(VM, StringString)
             pushc 1
             sum
             ret
-    )").to_string(-1), "HelloWorld");
+    )").to_string_ptr(-1), "HelloWorld");
 
     ASSERT_EQ(run(R"(
         .const
diff --git a/src/vm/value.cc b/src/vm/value.cc
index 07523b4..27f873c 100644
--- a/src/vm/value.cc
+++ b/src/vm/value.cc
@@ -41,4 +41,13 @@ std::string Value::to_string() const
     }, value_);
 }
 
+const char* Value::as_string_ptr() const
+{
+    if (auto s = std::get_if<std::string>(&value_))
+        return s->c_str();
+    if (auto s = std::get_if<const char*>(&value_))
+        return *s;
+    throw std::logic_error("Shouldn't get here");
+}
+
 }
diff --git a/src/vm/value.hh b/src/vm/value.hh
index 65c98ce..8bb2cde 100644
--- a/src/vm/value.hh
+++ b/src/vm/value.hh
@@ -26,6 +26,7 @@ public:
     static Value createInteger(int32_t v) { return Value(v); }
     static Value createFloat(float f) { return Value(f); }
     static Value createString(std::string const& str) { return Value(str); }
+    static Value createStringFromConstant(const char* str) { return Value(str); }
     static Value createFunctionId(FunctionId f_id) { return Value(Function { f_id }); }
 
     static Value createFalse() { return createInteger(0); }
@@ -36,13 +37,13 @@ public:
 
     [[nodiscard]] int32_t     as_integer() const     { return std::get<int32_t>(value_); }
     [[nodiscard]] float       as_float() const       { return std::get<float>(value_); }
-    [[nodiscard]] std::string as_string() const      { return std::get<std::string>(value_); }
+    [[nodiscard]] const char* as_string_ptr() const;
     [[nodiscard]] FunctionId  as_function_id() const { return std::get<Function>(value_).f_id; }
 
     [[nodiscard]] std::string to_string() const;
 
 private:
-    using Internal = std::variant<std::monostate, int32_t, float, std::string, Function>;
+    using Internal = std::variant<std::monostate, int32_t, float, std::string, const char*, Function>;
     Internal value_;
 
     explicit Value(Internal const& internal) : value_(internal) {}
diff --git a/src/vm/vm.cc b/src/vm/vm.cc
index ab8ac99..6afeb4a 100644
--- a/src/vm/vm.cc
+++ b/src/vm/vm.cc
@@ -49,11 +49,11 @@ float VM::to_float(int index) const
     throw VMTypeError(Type::Float, f.type());
 }
 
-std::string VM::to_string(int index) const
+const char* VM::to_string_ptr(int index) const
 {
-    Value i = stack_.at(index);
-    assert_type(i, Type::String);
-    return i.as_string();
+    Value s = stack_.at(index);
+    assert_type(s, Type::String);
+    return s.as_string_ptr();
 }
 
 VM& VM::push_nil()
@@ -110,8 +110,8 @@ void VM::step()
             auto cnst = code_.bytecode().get_constant(op.operator_);
             if (auto f = std::get_if<float>(&cnst))
                 push_float(*f);
-            else if (auto s = std::get_if<std::string>(&cnst))
-                push_string(*s);
+            else if (auto s = std::get_if<const char*>(&cnst))
+                stack_.push(Value::createStringFromConstant(*s));
             else
                 throw std::logic_error("Shouldn't get here");
             break;
diff --git a/src/vm/vm.hh b/src/vm/vm.hh
index 4367df6..848ed3c 100644
--- a/src/vm/vm.hh
+++ b/src/vm/vm.hh
@@ -31,7 +31,7 @@ public:
 
     [[nodiscard]] int32_t     to_integer(int index) const;
     [[nodiscard]] float       to_float(int index) const;
-    [[nodiscard]] std::string to_string(int index) const;
+    [[nodiscard]] const char* to_string_ptr(int index) const;
 
     [[nodiscard]] std::string debug_stack() const { return stack_.debug(); }