diff --git a/runtime/json.hpp b/runtime/json.hpp
index 8789356..38b73f2 100644
--- a/runtime/json.hpp
+++ b/runtime/json.hpp
@@ -295,8 +295,8 @@ public:
     auto parse_val() -> Res<std::unique_ptr<Value>>;
 
 private:
-    inline auto unexpected_tok_err(
-        TokTyp expected, std::string_view msg) -> Res<std::unique_ptr<Value>>
+    inline auto unexpected_tok_err(TokTyp expected, std::string_view msg)
+        -> Res<std::unique_ptr<Value>>
     {
         return Err {
             .pos = this->cur.val().pos,
diff --git a/runtime/main.cpp b/runtime/main.cpp
index 98843d2..51c3ac3 100644
--- a/runtime/main.cpp
+++ b/runtime/main.cpp
@@ -2,12 +2,91 @@
 #include "vm.hpp"
 #include <format>
 #include <iostream>
+#include <string>
 #include <utility>
 #include <variant>
 
+enum class AsmLineType {
+    Op,
+    Lit,
+    Loc,
+    Ref,
+};
+
+struct Loc {
+    explicit Loc(std::string value)
+        : value(value)
+    {
+    }
+
+    std::string value;
+};
+
+struct Ref {
+    explicit Ref(std::string value)
+        : value(value)
+    {
+    }
+
+    std::string value;
+};
+
+struct AsmLine {
+    /* clang-format off */
+    AsmLine(sliger::Op value) : type(AsmLineType::Op), value(value) {}
+    AsmLine(uint32_t value) : type(AsmLineType::Lit), value(value) {}
+    AsmLine(Loc value) : type(AsmLineType::Loc), value(value) {}
+    AsmLine(Ref value) : type(AsmLineType::Ref), value(value) {}
+    /* clang-format on */
+
+    AsmLineType type;
+    std::variant<sliger::Op, uint32_t, Loc, Ref> value;
+};
+
+auto compile_asm(const std::vector<AsmLine>& lines) -> std::vector<uint32_t>
+{
+    size_t ip = 0;
+    auto output = std::vector<uint32_t>();
+    auto locs = std::unordered_map<std::string, size_t>();
+    auto refs = std::unordered_map<size_t, std::string>();
+    for (const auto& line : lines) {
+        switch (line.type) {
+            case AsmLineType::Op: {
+                output.push_back(
+                    std::to_underlying(std::get<sliger::Op>(line.value)));
+                ip += 1;
+                break;
+            }
+            case AsmLineType::Lit: {
+                output.push_back(std::get<uint32_t>(line.value));
+                ip += 1;
+                break;
+            }
+            case AsmLineType::Loc: {
+                locs.insert_or_assign(std::get<Loc>(line.value).value, ip + 1);
+                break;
+            }
+            case AsmLineType::Ref: {
+                output.push_back(0);
+                refs.insert_or_assign(ip, std::get<Ref>(line.value).value);
+                ip += 1;
+                break;
+            }
+        }
+    }
+    for (size_t i = 0; i < output.size(); ++i) {
+        if (refs.contains(i)) {
+            output.at(i) = static_cast<uint32_t>(locs.at(refs.at(i)));
+        }
+    }
+    return output;
+}
+
 int main()
 {
-    using sliger::Op;
+    using R = Ref;
+    using L = Loc;
+    using enum sliger::Op;
 
     //  fn add(a, b) {
     //      + a b
@@ -21,101 +100,56 @@ int main()
     //      }
     //      result = add(result, 5);
     //  }
-    auto program = std::vector<uint32_t> {
-        std::to_underlying(Op::SourceMap),
-        0,
-        0,
-        0,
-        std::to_underlying(Op::PushPtr),
-        15, // main
-        std::to_underlying(Op::Call),
-        0,
-        std::to_underlying(Op::Pop),
-        std::to_underlying(Op::PushPtr),
-        87, // .l3
-        std::to_underlying(Op::Jump),
-        std::to_underlying(Op::Pop),
-        /*add*/ std::to_underlying(Op::SourceMap),
-        19,
-        2,
-        5,
-        std::to_underlying(Op::Add),
-        std::to_underlying(Op::Return),
-        /*main*/ std::to_underlying(Op::SourceMap),
-        28,
-        5,
-        1,
-        std::to_underlying(Op::PushInt),
-        0,
-        std::to_underlying(Op::SourceMap),
-        44,
-        6,
-        1,
-        std::to_underlying(Op::PushInt),
-        0,
-        std::to_underlying(Op::SourceMap),
-        55,
-        7,
-        1,
-        /*.l0*/ std::to_underlying(Op::SourceMap),
-        66,
-        8,
-        5,
-        std::to_underlying(Op::LoadLocal),
-        1,
-        std::to_underlying(Op::PushInt),
-        0,
-        std::to_underlying(Op::LessThan),
-        std::to_underlying(Op::Not),
-        std::to_underlying(Op::PushPtr),
-        53, // .l1
-        std::to_underlying(Op::JumpIfFalse),
-        std::to_underlying(Op::SourceMap),
-        87,
-        9,
-        9,
-        std::to_underlying(Op::PushPtr),
-        83, // .l2
-        std::to_underlying(Op::Jump),
-        /*.l1*/ std::to_underlying(Op::SourceMap),
-        104,
-        11,
-        5,
-        std::to_underlying(Op::LoadLocal),
-        0,
-        std::to_underlying(Op::PushInt),
-        5,
-        std::to_underlying(Op::PushPtr),
-        9, // add
-        std::to_underlying(Op::Call),
-        2,
-        std::to_underlying(Op::StoreLocal),
-        0,
-        std::to_underlying(Op::SourceMap),
-        133,
-        12,
-        5,
-        std::to_underlying(Op::LoadLocal),
-        1,
-        std::to_underlying(Op::PushInt),
-        1,
-        std::to_underlying(Op::Add),
-        std::to_underlying(Op::StoreLocal),
-        1,
-        std::to_underlying(Op::PushPtr),
-        33, // .l0
-        std::to_underlying(Op::Jump),
-        /*.l2*/ std::to_underlying(Op::Pop),
-        std::to_underlying(Op::Pop),
-        std::to_underlying(Op::PushNull),
-        std::to_underlying(Op::Return),
-        /*.l3*/ std::to_underlying(Op::SourceMap),
-        147,
-        15,
-        1,
-        std::to_underlying(Op::PushInt),
+    auto program_asm = std::vector<AsmLine> {
+        // clang-format off
+        SourceMap,  0, 0, 0,
+        PushPtr,    R("main"),
+        Pop,
+        PushPtr,    R("_exit"),
+        Jump,
+        Pop,
+        L("add"),
+        SourceMap,  19, 2, 5,
+        Add,
+        Return,
+        SourceMap,  28, 5, 1,
+        PushInt,    0,
+        SourceMap,  44, 6, 1,
+        PushInt,    0,
+        SourceMap,  55, 7, 1,
+        L("1"),
+        SourceMap,  66, 8,  5,
+        LoadLocal,  1,
+        PushInt,    0,
+        LessThan,
+        Not,
+        PushPtr,    R("1"),
+        JumpIfFalse,
+        SourceMap,  87, 9, 9,
+        PushPtr,    R("2"),
+        Jump,
+        SourceMap,  104, 11, 5,
+        LoadLocal,  0,
+        PushInt,    5,
+        PushPtr,    R("add"),
+        Call,       2,
+        StoreLocal, 0,
+        SourceMap,  133, 12, 5,
+        LoadLocal,  1,
+        PushInt,    1,
+        Add,
+        StoreLocal, 1,
+        PushPtr,    R("0"),
+        Jump,
+        L("2"),
+        Pop,
+        PushNull,
+        Return,
+        L("_exit"),
+        SourceMap,  147, 15, 1
+        // clang-format on
     };
-
+    auto program = compile_asm(program_asm);
     auto vm = sliger::VM(program,
         {
             .flame_graph = true,
diff --git a/runtime/to_json_2.cpp b/runtime/to_json_2.cpp
new file mode 100644
index 0000000..a8df02c
--- /dev/null
+++ b/runtime/to_json_2.cpp
@@ -0,0 +1,14 @@
+#include "json.hpp"
+#include "vm.hpp"
+
+using namespace sliger;
+
+void FlameGraphBuilder::to_json(json::Writer& writer) const
+{
+    writer.add("null");
+}
+
+void CodeCoverageBuilder::to_json(json::Writer& writer) const
+{
+    writer.add("null");
+}