diff --git a/src/builtins.c b/src/builtins.c
index d75e860..cdc76f2 100644
--- a/src/builtins.c
+++ b/src/builtins.c
@@ -182,3 +182,15 @@ struct ucl_object *ucl_builtin_list(struct ucl_state *state, struct ucl_object *
 
     return head;
 }
+
+LISP_FUNC_2(ucl_builtin_mapcar, state, fun, elems) {
+    // TODO: Support arbitrary number of 'elems' lists
+    struct ucl_object *result = ucl_nil_create();
+    FOREACH_LIST(elems, iter, elem) {
+        struct ucl_object *form = ucl_tuple_create(fun, elem);
+        struct ucl_object *value = ucl_evaluate(state, form);
+        UCL_RET_IF_ERROR(value);
+        ucl_list_append(result, value);
+    }
+    return result;
+}
diff --git a/src/builtins.h b/src/builtins.h
index 4cc65fe..1b4053b 100644
--- a/src/builtins.h
+++ b/src/builtins.h
@@ -23,6 +23,8 @@ struct ucl_object *ucl_builtin_car(struct ucl_state *state, struct ucl_object *a
 struct ucl_object *ucl_builtin_cdr(struct ucl_state *state, struct ucl_object *args);
 struct ucl_object *ucl_builtin_nth(struct ucl_state *state, struct ucl_object *args);
 struct ucl_object *ucl_builtin_list(struct ucl_state *state, struct ucl_object *args);
+struct ucl_object *ucl_builtin_mapcar(struct ucl_state *state, struct ucl_object *args);
+
 struct ucl_object *ucl_builtin_print(struct ucl_state *state, struct ucl_object *args);
 struct ucl_object *ucl_builtin_printl(struct ucl_state *state, struct ucl_object *args);
 
diff --git a/src/evaluate.c b/src/evaluate.c
index 7c478db..f611fc9 100644
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -15,6 +15,7 @@ struct ucl_object *ucl_evaluate_builtin_form(struct ucl_state *state, struct ucl
 
     FOREACH_LIST(list, iter, item) {
         struct ucl_object *obj = ucl_evaluate(state, item);
+        UCL_RET_IF_ERROR(obj);
         ucl_list_append(evaluated_list, obj);
     };
 
@@ -47,20 +48,7 @@ struct ucl_object *ucl_evaluate_special_form(struct ucl_state *state, struct ucl
     // TODO: Recursively eval args
     const char *fun_sym = ucl_car(list)->symbol;
 
-    struct ucl_object *fun = ucl_state_get(state, ucl_car(list)->symbol);
-    struct ucl_object *args = ucl_cdr(list);
-    struct ucl_object *result = NULL;
-
-    result = fun->special(state, args);
-
-    return result;
-}
-
-struct ucl_object *ucl_evaluate_lisp_form(struct ucl_state *state, struct ucl_object *list) {
-    // TODO: Recursively eval args
-    const char *fun_sym = ucl_car(list)->symbol;
-
-    struct ucl_object *fun = ucl_state_get(state, ucl_car(list)->symbol);
+    struct ucl_object *fun = ucl_state_get(state, fun_sym);
     struct ucl_object *args = ucl_cdr(list);
     struct ucl_object *result = NULL;
 
@@ -74,11 +62,7 @@ struct ucl_object *ucl_evaluate_list(struct ucl_state *state, struct ucl_object
         return list;
     }
 
-    struct ucl_object *fun_sym = ucl_car(list);
-    if (fun_sym->type != UCL_TYPE_SYMBOL) {
-        return ucl_error_create("Unknown function symbol");
-    }
-    struct ucl_object *fun = ucl_state_get(state, fun_sym->symbol);
+    struct ucl_object *fun = ucl_evaluate(state, ucl_car(list));
     UCL_RET_IF_ERROR(fun);
 
     if (fun->type == UCL_TYPE_SPECIAL) {
diff --git a/src/main.c b/src/main.c
index 9836640..95ac9c4 100644
--- a/src/main.c
+++ b/src/main.c
@@ -26,7 +26,6 @@ int main(int argc, const char **argv) {
 
     ucl_state_put(state, "print", ucl_builtin_create(ucl_builtin_print));
     ucl_state_put(state, "printl", ucl_builtin_create(ucl_builtin_printl));
-    ucl_state_put(state, "list", ucl_builtin_create(ucl_builtin_list));
     // TODO:
     //   - object -> string
     //   - formatted printing?
@@ -47,9 +46,13 @@ int main(int argc, const char **argv) {
     ucl_state_put(state, "string-p", ucl_builtin_create(ucl_builtin_string_p));
     ucl_state_put(state, "int-p", ucl_builtin_create(ucl_builtin_int_p));
     ucl_state_put(state, "list-p", ucl_builtin_create(ucl_builtin_list_p));
+
+    ucl_state_put(state, "list", ucl_builtin_create(ucl_builtin_list));
     ucl_state_put(state, "car", ucl_builtin_create(ucl_builtin_car));
     ucl_state_put(state, "cdr", ucl_builtin_create(ucl_builtin_cdr));
     ucl_state_put(state, "nth", ucl_builtin_create(ucl_builtin_nth));
+    ucl_state_put(state, "mapcar", ucl_builtin_create(ucl_builtin_mapcar));
+
     // TODO:
     //   - equality
     //   - map
diff --git a/src/special.c b/src/special.c
index 67420cc..e82ac50 100644
--- a/src/special.c
+++ b/src/special.c
@@ -27,7 +27,7 @@ struct ucl_object *ucl_special_let(struct ucl_state *state, struct ucl_object *a
         ucl_state_put(let_state, sym->symbol, value);
     }
 
-    struct ucl_object *result = ucl_progn(state, expressions);
+    struct ucl_object *result = ucl_progn(let_state, expressions);
     ucl_state_delete(let_state);
     return result;
 }
@@ -95,7 +95,7 @@ struct ucl_object *ucl_special_setq(struct ucl_state *state, struct ucl_object *
 
     ucl_state_put(root_state, sym->symbol, value);
 
-    return sym;
+    return value;
 }
 
 struct ucl_object *ucl_special_progn(struct ucl_state *state, struct ucl_object *args) {
diff --git a/src/utility.c b/src/utility.c
index 93bf12f..ef11613 100644
--- a/src/utility.c
+++ b/src/utility.c
@@ -73,7 +73,7 @@ struct ucl_object *ucl_list_length(struct ucl_object *list) {
 struct ucl_object *ucl_list_nth(struct ucl_object *list, int n) {
     UCL_COND_OR_RET_ERROR(
         list != NULL && list->type == UCL_TYPE_CELL,
-        "Invalid type of argument 0 to 'ucl_list_'");
+        "Invalid type of argument 0 to 'ucl_list_nth'");
 
     int length = ucl_list_length(list)->integer;
     UCL_COND_OR_RET_ERROR(length > n, "Position n >= list length in ucl_list_nth");
diff --git a/test/test_e2e.c b/test/test_e2e.c
index 19c8b88..76974ec 100644
--- a/test/test_e2e.c
+++ b/test/test_e2e.c
@@ -24,6 +24,13 @@ void setUp(void) {
     ucl_state_put(state, "+", ucl_builtin_create(ucl_builtin_add));
     ucl_state_put(state, "error", ucl_builtin_create(ucl_builtin_error));
     ucl_state_put(state, "list", ucl_builtin_create(ucl_builtin_list));
+    ucl_state_put(state, "setq", ucl_special_create(ucl_special_setq));
+    ucl_state_put(state, "car", ucl_builtin_create(ucl_builtin_car));
+    ucl_state_put(state, "cdr", ucl_builtin_create(ucl_builtin_cdr));
+    ucl_state_put(state, "nth", ucl_builtin_create(ucl_builtin_nth));
+    ucl_state_put(state, "mapcar", ucl_builtin_create(ucl_builtin_mapcar));
+    ucl_state_put(state, "lambda", ucl_special_create(ucl_special_lambda));
+    ucl_state_put(state, "quote", ucl_special_create(ucl_special_quote));
 }
 
 void tearDown(void) {
@@ -130,6 +137,108 @@ void test_eval_defun(void) {
     TEST_ASSERT_EQUAL_STRING(response->symbol, "foo");
 }
 
+void test_call_function(void) {
+    response = eval("(defun foo (a b) (+ a b))");
+
+    TEST_ASSERT_OBJ_SYMBOL(response);
+    TEST_ASSERT_EQUAL_STRING(response->symbol, "foo");
+
+    response = eval("(foo 2 3)");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 5);
+}
+
+void test_setq(void) {
+    response = eval("(setq bar 2)");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->symbol, 2);
+
+    response = eval("bar");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->symbol, 2);
+}
+
+void test_setq_from_function(void) {
+    response = eval("(defun foo (a) (setq bar a))");
+
+    TEST_ASSERT_OBJ_SYMBOL(response);
+    TEST_ASSERT_EQUAL_STRING(response->symbol, "foo");
+
+    response = eval("(foo 2)");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->symbol, 2);
+
+    response = eval("bar");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->symbol, 2);
+}
+
+void test_lambda(void) {
+    response = eval("((lambda (x) (+ x 2)) 2)");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 4);
+}
+
+void test_mapcar_lambda(void) {
+    response = eval("(car (mapcar (quote (lambda (x) (+ x 2))) (list 5)))");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 7);
+}
+
+void test_mapcar_function(void) {
+    response = eval("(defun foo (a) (+ a 2))");
+
+    TEST_ASSERT_OBJ_SYMBOL(response);
+    TEST_ASSERT_EQUAL_STRING(response->symbol, "foo");
+
+    response = eval("(car (mapcar (quote foo) (list 5)))");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 7);
+}
+
+void test_car(void) {
+    response = eval("(car (list 2 3 4))");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 2);
+}
+
+void test_cdr(void) {
+    response = eval("(car (cdr (list 2 3 4)))");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 3);
+}
+
+void test_nth_0(void) {
+    response = eval("(nth 0 (list 2 3 4))");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 2);
+}
+
+void test_nth_1(void) {
+    response = eval("(nth 1 (list 2 3 4))");
+
+    TEST_ASSERT_OBJ_INT(response);
+    TEST_ASSERT_EQUAL(response->integer, 3);
+}
+
+void test_nth_oob(void) {
+    response = eval("(nth 3 (list 2 3 4))");
+
+    TEST_ASSERT_OBJ_ERROR(response);
+}
+
+
 int main(void) {
     UNITY_BEGIN();
 
@@ -147,6 +256,17 @@ int main(void) {
     RUN_TEST(test_eval_nested_error);
     RUN_TEST(test_eval_list);
     RUN_TEST(test_eval_defun);
+    RUN_TEST(test_call_function);
+    RUN_TEST(test_setq);
+    RUN_TEST(test_setq_from_function);
+    RUN_TEST(test_lambda);
+    RUN_TEST(test_mapcar_lambda);
+    RUN_TEST(test_car);
+    RUN_TEST(test_cdr);
+    RUN_TEST(test_nth_0);
+    RUN_TEST(test_nth_1);
+    RUN_TEST(test_nth_oob);
+
 
     return UNITY_END();
 }