diff --git a/src/ast.cpp b/src/ast.cpp
index 0ee4ee1..dd18fe1 100644
--- a/src/ast.cpp
+++ b/src/ast.cpp
@@ -49,7 +49,16 @@ namespace AST {
     std::string Function::formatted() {
         std::stringstream out{ "" };
         out << this->m_name;
-        out << "() -> ";
+        out << "(";
+
+        int counter = 0;
+        for (auto& param : this->m_params) {
+            if (counter++ > 0)
+                out << ", ";
+            out << param.second->formatted() << " " << param.first;
+        }
+
+        out << ") -> ";
         out << this->m_return_ty->formatted();
         out << " {\n";
         for (auto& statement : this->m_statements) {
diff --git a/src/codegen.cpp b/src/codegen.cpp
index 0f00f4d..6cf21d3 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -115,6 +115,9 @@ namespace AST {
 
         auto ret_ty = this->m_return_ty->codegen(builder);
         std::vector<llvm::Type*> params{};
+        for (auto& param : this->m_params) {
+            params.push_back(param.second->codegen(builder));
+        }
 
 
         auto fn_ty = llvm::FunctionType::get(ret_ty, params, false);
diff --git a/src/parsing.cpp b/src/parsing.cpp
index 7471f07..d6126c8 100644
--- a/src/parsing.cpp
+++ b/src/parsing.cpp
@@ -175,6 +175,17 @@ namespace parsing {
             auto type = parse_type(inner).unwrap();
             auto name_token = inner.expect(token::Type::Ident);
             inner.expect(token::Type::Symbol, "(");
+
+            std::vector<std::pair<std::string, std::unique_ptr<types::Type>>> params;
+            while (inner.peek().content != ")") {
+                if (params.size() > 0) {
+                    inner.expect(token::Type::Symbol, ",");
+                }
+                auto param_ty = parse_type(inner).unwrap();
+                auto param_name = inner.expect(token::Type::Ident);
+                params.push_back(std::pair(param_name.content, std::move(param_ty)));
+            }
+
             inner.expect(token::Type::Symbol, ")");
             inner.expect(token::Type::Symbol, "{");
 
@@ -191,7 +202,7 @@ namespace parsing {
 
             stream.m_position = inner.m_position;
 
-            auto fun = new AST::Function{ std::move(type), {}, name_token.content, std::move(statements) };
+            auto fun = new AST::Function{ std::move(type), std::move(params), name_token.content, std::move(statements) };
             return new std::unique_ptr<AST::TopLevelStatement>{ fun };
         }
         catch (std::runtime_error error) {
diff --git a/test.c b/test.c
index 7eb00a6..9f182a7 100644
--- a/test.c
+++ b/test.c
@@ -1,3 +1,7 @@
+int fibonacci(int n, int b) {
+    return 0;
+}
+
 int main() {
     int a = 5;
     a = 15 + 20;