diff --git a/clean.sh b/clean.sh
index f466c62..f618bdf 100755
--- a/clean.sh
+++ b/clean.sh
@@ -2,4 +2,5 @@
 
 rm -f brb
 rm -f *.o
+rm -f *.asm
 rm -rf *.dSYM
\ No newline at end of file
diff --git a/src/CodeGenerator.cpp b/src/CodeGenerator.cpp
index 0abd80c..7c7b0af 100644
--- a/src/CodeGenerator.cpp
+++ b/src/CodeGenerator.cpp
@@ -5,7 +5,7 @@ using namespace std;
 CodeGenerator::CodeGenerator(shared_ptr<llvm::Module> module): module(module) {
 }
 
-void CodeGenerator::generateObjectFile(string fileName) {
+void CodeGenerator::generateObjectFile(OutputKind outputKind) {
     llvm::InitializeAllTargetInfos();
     llvm::InitializeAllTargets();
     llvm::InitializeAllTargetMCs();
@@ -26,6 +26,19 @@ void CodeGenerator::generateObjectFile(string fileName) {
     module->setDataLayout(targetMachine->createDataLayout());
     module->setTargetTriple(targetTriple);
 
+    string fileName;
+    llvm::CodeGenFileType codeGenFileType;
+    switch (outputKind) {
+        case OutputKind::ASSEMBLY:
+            fileName = string(module->getName()) + ".asm";
+            codeGenFileType = llvm::CodeGenFileType::AssemblyFile;
+            break;
+        case OutputKind::OBJECT:
+            fileName = string(module->getName()) + ".o";
+            codeGenFileType = llvm::CodeGenFileType::ObjectFile;
+            break;
+    }
+
     error_code errorCode;
     llvm::raw_fd_ostream outputFile(fileName, errorCode, llvm::sys::fs::OF_None);
     if (errorCode) {
@@ -34,8 +47,8 @@ void CodeGenerator::generateObjectFile(string fileName) {
     }
 
     llvm::legacy::PassManager passManager;
-    if (targetMachine->addPassesToEmitFile(passManager, outputFile, nullptr, llvm::CodeGenFileType::AssemblyFile)) {
-        cerr << "Failed to emit file" << endl;
+    if (targetMachine->addPassesToEmitFile(passManager, outputFile, nullptr, codeGenFileType)) {
+        cerr << "Failed to generate file " << fileName << endl;
         exit(1);
     }
 
diff --git a/src/CodeGenerator.h b/src/CodeGenerator.h
index 5dc3a44..48efa5d 100644
--- a/src/CodeGenerator.h
+++ b/src/CodeGenerator.h
@@ -14,12 +14,18 @@
 using namespace std;
 
 class CodeGenerator {
+public:
+    enum class OutputKind {
+        ASSEMBLY,
+        OBJECT
+    };
+
 private:
     shared_ptr<llvm::Module> module;
 
 public:
     CodeGenerator(shared_ptr<llvm::Module> module);
-    void generateObjectFile(string fileName);
+    void generateObjectFile(OutputKind outputKind);
 };
 
 #endif
\ No newline at end of file
diff --git a/src/ModuleBuilder.cpp b/src/ModuleBuilder.cpp
index caddce7..29670cf 100644
--- a/src/ModuleBuilder.cpp
+++ b/src/ModuleBuilder.cpp
@@ -51,7 +51,7 @@ void ModuleBuilder::buildFunctionDeclaration(shared_ptr<StatementFunctionDeclara
 
     // build function declaration
     llvm::FunctionType *funType = llvm::FunctionType::get(typeForValueType(statement->getReturnValueType()), types, false);
-    llvm::Function *fun = llvm::Function::Create(funType, llvm::GlobalValue::InternalLinkage, statement->getName(), module.get());
+    llvm::Function *fun = llvm::Function::Create(funType, llvm::GlobalValue::ExternalLinkage, statement->getName(), module.get());
     funMap[statement->getName()] = fun;
 
     // define function body
diff --git a/src/main.cpp b/src/main.cpp
index f9b2f36..f6ecc7a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -37,8 +37,15 @@ void versionPrinter(llvm::raw_ostream &os) {
 int main(int argc, char **argv) {
     llvm::cl::SetVersionPrinter(versionPrinter);
     llvm::cl::extrahelp("\nADDITIONAL HELP:\n\n  This is the extra help\n");
-
     llvm::cl::opt<bool> isVerbose("v", llvm::cl::desc("Verbos output"), llvm::cl::init(false));
+    llvm::cl::opt<CodeGenerator::OutputKind> outputKind(
+        llvm::cl::desc("Choose generated output:"),
+        llvm::cl::init(CodeGenerator::OutputKind::OBJECT),
+        llvm::cl::values(
+            clEnumValN(CodeGenerator::OutputKind::OBJECT, "c", "Generate object file"),
+            clEnumValN(CodeGenerator::OutputKind::ASSEMBLY, "S", "Generate assembly file")
+        )
+    );
     llvm::cl::opt<string> inputFileName(llvm::cl::Positional, llvm::cl::desc("<input file>"), llvm::cl::Required);
     llvm::cl::ParseCommandLineOptions(argc, argv, "Bits Runner Builder - LLVM based compiler for the Bits Runner Code language");
 
@@ -73,8 +80,8 @@ int main(int argc, char **argv) {
         module->print(llvm::outs(), nullptr);
     }
 
-    //CodeGenerator codeGenerator(module);
-    //codeGenerator.generateObjectFile("dummy.s");
+    CodeGenerator codeGenerator(module);
+    codeGenerator.generateObjectFile(outputKind);
 
     return 0;
 }
\ No newline at end of file