diff --git a/lang/src/codegen.rs b/lang/src/codegen.rs
index cda4d2b..bbca41f 100644
--- a/lang/src/codegen.rs
+++ b/lang/src/codegen.rs
@@ -1352,7 +1352,7 @@ impl Codegen {
                     ),
                 }
             }
-            E::BinOp { left, op: T::Decl, right } if self.has_ct(left) => {
+            E::BinOp { left, op: T::Decl, right, .. } if self.has_ct(left) => {
                 let slot_base = self.ct.vm.read_reg(reg::STACK_PTR).0;
                 let (cnt, ty) = self.eval_const_low(self.ci.file, right, None);
                 if self.assign_ct_pattern(left, ty, cnt as _) {
@@ -1360,7 +1360,7 @@ impl Codegen {
                 }
                 Some(Value::void())
             }
-            E::BinOp { left, op: T::Decl, right } => {
+            E::BinOp { left, op: T::Decl, right, .. } => {
                 let value = self.expr(right)?;
                 self.assign_pattern(left, value)
             }
@@ -1506,7 +1506,7 @@ impl Codegen {
             E::If { cond, then, mut else_, .. } => {
                 let mut then = Some(then);
                 let jump_offset;
-                if let &E::BinOp { left, op, right } = cond
+                if let &E::BinOp { left, op, right, .. } = cond
                     && let ty = self.infer_type(left)
                     && let Some((op, swapped)) = op.cond_op(ty.is_signed())
                 {
@@ -1605,7 +1605,7 @@ impl Codegen {
                 self.ci.emit(jmp(loop_.offset as i32 - offset as i32));
                 None
             }
-            E::BinOp { left, op: op @ (T::And | T::Or), right } => {
+            E::BinOp { left, op: op @ (T::And | T::Or), right, .. } => {
                 let lhs = self.expr_ctx(left, Ctx::default().with_ty(ty::BOOL))?;
                 let lhs = self.loc_to_reg(lhs.loc, 1);
                 let jump_offset = self.ci.code.len() + 3;
@@ -1622,7 +1622,7 @@ impl Codegen {
 
                 Some(Value { ty: ty::Id::BOOL, loc: Loc::reg(lhs) })
             }
-            E::BinOp { left, op, right } if op != T::Decl => 'ops: {
+            E::BinOp { left, op, right, .. } if op != T::Decl => 'ops: {
                 let left = self.expr_ctx(left, Ctx {
                     ty: ctx.ty.filter(|_| op.is_homogenous()),
                     check: ctx.check,
diff --git a/lang/src/fmt.rs b/lang/src/fmt.rs
index 05ade5c..54c3f4f 100644
--- a/lang/src/fmt.rs
+++ b/lang/src/fmt.rs
@@ -358,7 +358,8 @@ impl<'a> Formatter<'a> {
             Expr::BinOp {
                 left,
                 op: TokenKind::Assign,
-                right: &Expr::BinOp { left: lleft, op, right },
+                right: &Expr::BinOp { left: lleft, op, right, .. },
+                ..
             } if left.pos() == lleft.pos() => {
                 self.fmt(left, f)?;
                 f.write_str(" ")?;
@@ -366,7 +367,7 @@ impl<'a> Formatter<'a> {
                 f.write_str("= ")?;
                 self.fmt(right, f)
             }
-            Expr::BinOp { right, op, left } => {
+            Expr::BinOp { right, op, left, .. } => {
                 let prec_miss_left = |e: &Expr| {
                     matches!(
                         e, Expr::BinOp { op: lop, .. } if op.precedence() > lop.precedence()
diff --git a/lang/src/parser.rs b/lang/src/parser.rs
index 1032164..de3b1d5 100644
--- a/lang/src/parser.rs
+++ b/lang/src/parser.rs
@@ -159,7 +159,7 @@ impl<'a, 'b> Parser<'a, 'b> {
                 break;
             }
 
-            let op = self.next().kind;
+            let Token { kind: op, start: pos, .. } = self.next();
 
             if op == TokenKind::Decl {
                 self.declare_rec(&fold, top_level);
@@ -172,10 +172,15 @@ impl<'a, 'b> Parser<'a, 'b> {
 
             if let Some(op) = op.ass_op() {
                 self.flag_idents(*left, idfl::MUTABLE);
-                let right = Expr::BinOp { left: self.arena.alloc(fold), op, right };
-                fold = Expr::BinOp { left, op: TokenKind::Assign, right: self.arena.alloc(right) };
+                let right = Expr::BinOp { left: self.arena.alloc(fold), pos, op, right };
+                fold = Expr::BinOp {
+                    left,
+                    pos,
+                    op: TokenKind::Assign,
+                    right: self.arena.alloc(right),
+                };
             } else {
-                fold = Expr::BinOp { left, right, op };
+                fold = Expr::BinOp { left, right, pos, op };
                 if op == TokenKind::Assign {
                     self.flag_idents(*left, idfl::MUTABLE);
                 }
@@ -762,6 +767,7 @@ generate_expr! {
         /// `Expr OP Expr`
         BinOp {
             left:  &'a Self,
+            pos: Pos,
             op:    TokenKind,
             right: &'a Self,
         },
diff --git a/lang/src/son.rs b/lang/src/son.rs
index dcad7bd..46fb4e1 100644
--- a/lang/src/son.rs
+++ b/lang/src/son.rs
@@ -2265,7 +2265,7 @@ impl<'a> Codegen<'a> {
                 }
                 Some(self.ci.nodes.new_node_lit(val.ty, Kind::UnOp { op }, [VOID, val.id]))
             }
-            Expr::BinOp { left, op: TokenKind::Decl, right } => {
+            Expr::BinOp { left, op: TokenKind::Decl, right, .. } => {
                 let mut right = self.expr(right)?;
                 if right.ty.loc(&self.tys) == Loc::Stack {
                     let stck = self.ci.nodes.new_node_nop(right.ty, Kind::Stck, [VOID, MEM]);
@@ -2276,11 +2276,11 @@ impl<'a> Codegen<'a> {
                 self.assign_pattern(left, right);
                 Some(Value::VOID)
             }
-            Expr::BinOp { left, op: TokenKind::Assign, right } => {
+            Expr::BinOp { left, pos, op: TokenKind::Assign, right } => {
                 let dest = self.raw_expr(left)?;
                 let mut value = self.expr_ctx(right, Ctx::default().with_ty(dest.ty))?;
 
-                self.assert_ty(left.pos(), &mut value, dest.ty, "assignment source");
+                self.assert_ty(pos, &mut value, dest.ty, "assignment source");
 
                 if dest.var {
                     let var = &mut self.ci.scope.vars[(u16::MAX - dest.id) as usize];
@@ -2295,12 +2295,12 @@ impl<'a> Codegen<'a> {
                 } else if dest.ptr {
                     self.store_mem(dest.id, dest.ty, value.id);
                 } else {
-                    self.report(left.pos(), "cannot assign to this expression");
+                    self.report(pos, "cannot assign to this expression");
                 }
 
                 Some(Value::VOID)
             }
-            Expr::BinOp { left, op, right }
+            Expr::BinOp { left, pos, op, right }
                 if !matches!(op, TokenKind::Assign | TokenKind::Decl) =>
             {
                 let mut lhs = self.raw_expr_ctx(left, ctx)?;
@@ -2316,7 +2316,7 @@ impl<'a> Codegen<'a> {
                         self.ci.nodes.unlock(lhs.id);
                         let mut rhs = rhs?;
                         self.strip_var(&mut rhs);
-                        let ty = self.binop_ty(right.pos(), &mut lhs, &mut rhs, op);
+                        let ty = self.binop_ty(pos, &mut lhs, &mut rhs, op);
                         let inps = [VOID, lhs.id, rhs.id];
                         Some(self.ci.nodes.new_node_lit(
                             ty::bin_ret(ty, op),
@@ -2330,15 +2330,15 @@ impl<'a> Codegen<'a> {
                         self.ci.nodes.unlock(lhs.id);
                         let mut rhs = rhs?;
                         self.strip_var(&mut rhs);
-                        self.assert_ty(right.pos(), &mut rhs, lhs.ty, "struct operand");
+                        self.assert_ty(pos, &mut rhs, lhs.ty, "struct operand");
                         let dst = self.ci.nodes.new_node(lhs.ty, Kind::Stck, [VOID, MEM]);
                         self.struct_op(left.pos(), op, s, dst, lhs.id, rhs.id);
                         Some(Value::ptr(dst).ty(lhs.ty))
                     }
                     _ => {
                         self.report(
-                            left.pos(),
-                            fa!("'{0} {op} {0}' is not supported", self.ty_display(lhs.ty),),
+                            pos,
+                            fa!("'{} {op} _' is not supported", self.ty_display(lhs.ty)),
                         );
                         Value::NEVER
                     }
diff --git a/lang/tests/son_tests_arrays.txt b/lang/tests/son_tests_arrays.txt
index b1783fe..69efca3 100644
--- a/lang/tests/son_tests_arrays.txt
+++ b/lang/tests/son_tests_arrays.txt
@@ -4,9 +4,9 @@ main:
     LI64 r7, 4d
     LI64 r8, 2d
     LI64 r9, 1d
-    LI64 r6, 1d
-    LI64 r10, 255d
-    LI64 r11, 0d
+    LI8 r6, 1b
+    LI8 r10, 255b
+    LI8 r11, 0b
     ADDI64 r12, r254, 0d
     ST r11, r254, 0a, 1h
     ST r11, r254, 1a, 1h
@@ -24,14 +24,14 @@ main:
     ADDI64 r254, r254, 36d
     JALA r0, r31, 0a
 pass:
-    LD r3, r2, 8a, 8h
-    MULI64 r8, r3, 8d
+    LD r4, r2, 8a, 8h
+    MULI64 r8, r4, 8d
     ADD64 r10, r8, r2
     LD r8, r10, 0a, 8h
-    LD r9, r2, 0a, 8h
-    ADD64 r11, r3, r9
+    LD r7, r2, 0a, 8h
+    ADD64 r11, r4, r7
     ADD64 r1, r8, r11
     JALA r0, r31, 0a
-code size: 348
+code size: 327
 ret: 8
 status: Ok(())
diff --git a/lang/tests/son_tests_c_strings.txt b/lang/tests/son_tests_c_strings.txt
index 34feef6..782ffb0 100644
--- a/lang/tests/son_tests_c_strings.txt
+++ b/lang/tests/son_tests_c_strings.txt
@@ -12,7 +12,7 @@ main:
     ADDI64 r254, r254, 16d
     JALA r0, r31, 0a
 str_len:
-    LI64 r6, 0d
+    LI8 r6, 0b
     LI64 r1, 0d
  2: LD r8, r2, 0a, 1h
     ANDI r8, r8, 255d
@@ -23,6 +23,6 @@ str_len:
     ADDI64 r1, r1, 1d
     JMP :2
  1: JALA r0, r31, 0a
-code size: 226
+code size: 219
 ret: 16
 status: Ok(())
diff --git a/lang/tests/son_tests_different_types.txt b/lang/tests/son_tests_different_types.txt
index 45dfca4..ae9a9db 100644
--- a/lang/tests/son_tests_different_types.txt
+++ b/lang/tests/son_tests_different_types.txt
@@ -1,9 +1,9 @@
 main:
     ADDI64 r254, r254, -24d
-    LI64 r6, 2d
-    LI64 r5, 0d
-    LI64 r8, 0d
-    LI64 r9, 255d
+    LI32 r6, 2w
+    LI32 r5, 0w
+    LI8 r8, 0b
+    LI8 r9, 255b
     ADDI64 r10, r254, 0d
     ADDI64 r7, r254, 12d
     ST r9, r254, 12a, 1h
@@ -43,6 +43,6 @@ main:
     ANDI r1, r12, 4294967295d
  1: ADDI64 r254, r254, 24d
     JALA r0, r31, 0a
-code size: 449
+code size: 427
 ret: 512
 status: Ok(())
diff --git a/lang/tests/son_tests_generic_functions.txt b/lang/tests/son_tests_generic_functions.txt
index c2b5557..eb53bd7 100644
--- a/lang/tests/son_tests_generic_functions.txt
+++ b/lang/tests/son_tests_generic_functions.txt
@@ -7,7 +7,7 @@ add:
 main:
     ADDI64 r254, r254, -16d
     ST r31, r254, 0a, 16h
-    LI64 r3, 2d
+    LI32 r3, 2w
     CP r2, r3
     JAL r31, r0, :add
     CP r32, r1
@@ -20,6 +20,6 @@ main:
     LD r31, r254, 0a, 16h
     ADDI64 r254, r254, 16d
     JALA r0, r31, 0a
-code size: 165
+code size: 161
 ret: 0
 status: Ok(())
diff --git a/lang/tests/son_tests_idk.txt b/lang/tests/son_tests_idk.txt
index ed973f3..f9b3b0f 100644
--- a/lang/tests/son_tests_idk.txt
+++ b/lang/tests/son_tests_idk.txt
@@ -1,20 +1,20 @@
 main:
     ADDI64 r254, r254, -128d
-    LI64 r6, 69d
+    LI8 r7, 69b
     LI64 r5, 128d
-    LI64 r7, 0d
+    LI64 r6, 0d
     ADDI64 r4, r254, 0d
- 2: JLTU r7, r5, :0
-    LD r2, r254, 42a, 1h
-    ANDI r1, r2, 255d
+ 2: JLTU r6, r5, :0
+    LD r3, r254, 42a, 1h
+    ANDI r1, r3, 255d
     JMP :1
- 0: ADDI64 r8, r7, 1d
-    ADD64 r3, r7, r4
-    ST r6, r3, 0a, 1h
-    CP r7, r8
+ 0: ADDI64 r8, r6, 1d
+    ADD64 r6, r6, r4
+    ST r7, r6, 0a, 1h
+    CP r6, r8
     JMP :2
  1: ADDI64 r254, r254, 128d
     JALA r0, r31, 0a
-code size: 152
+code size: 145
 ret: 69
 status: Ok(())
diff --git a/lang/tests/son_tests_intcast_store.txt b/lang/tests/son_tests_intcast_store.txt
index d051b3f..2b76f16 100644
--- a/lang/tests/son_tests_intcast_store.txt
+++ b/lang/tests/son_tests_intcast_store.txt
@@ -15,8 +15,8 @@ main:
     JALA r0, r31, 0a
 set:
     ADDI64 r254, r254, -25d
-    LI64 r9, 8d
-    LI64 r8, 5d
+    LI32 r9, 8w
+    LI8 r8, 5b
     ANDI r10, r4, 4294967295d
     ADDI64 r1, r254, 0d
     ST r8, r254, 0a, 1h
@@ -27,6 +27,6 @@ set:
     LD r1, r254, 1a, 4h
     ADDI64 r254, r254, 25d
     JALA r0, r31, 0a
-code size: 309
+code size: 298
 ret: 1024
 status: Ok(())
diff --git a/lang/tests/son_tests_request_page.txt b/lang/tests/son_tests_request_page.txt
index 38d1f4a..1c088ce 100644
--- a/lang/tests/son_tests_request_page.txt
+++ b/lang/tests/son_tests_request_page.txt
@@ -7,7 +7,7 @@ create_back_buffer:
     JAL r31, r0, :request_page
     JMP :1
  0: CP r33, r2
-    LI64 r34, 255d
+    LI8 r34, 255b
     CP r2, r34
     JAL r31, r0, :request_page
     CP r35, r1
@@ -45,6 +45,6 @@ request_page:
     ST r12, r4, 1a, 1h
     ECA 
     JALA r0, r31, 0a
-code size: 346
+code size: 339
 ret: 42
 status: Ok(())
diff --git a/lang/tests/son_tests_struct_operators.txt b/lang/tests/son_tests_struct_operators.txt
index d48dd36..df05924 100644
--- a/lang/tests/son_tests_struct_operators.txt
+++ b/lang/tests/son_tests_struct_operators.txt
@@ -1,8 +1,8 @@
 main:
     ADDI64 r254, r254, -168d
-    LI64 r11, 4d
-    LI64 r5, 1d
-    LI64 r3, 0d
+    LI8 r11, 4b
+    LI8 r5, 1b
+    LI8 r3, 0b
     ADDI64 r6, r254, 144d
     ADDI64 r6, r254, 148d
     ST r3, r254, 148a, 1h
@@ -115,6 +115,6 @@ main:
     ADD64 r1, r5, r3
  1: ADDI64 r254, r254, 168d
     JALA r0, r31, 0a
-code size: 1247
+code size: 1226
 ret: 10
 status: Ok(())
diff --git a/lang/tests/son_tests_struct_patterns.txt b/lang/tests/son_tests_struct_patterns.txt
index cebce40..7b19b93 100644
--- a/lang/tests/son_tests_struct_patterns.txt
+++ b/lang/tests/son_tests_struct_patterns.txt
@@ -34,7 +34,7 @@ fib_iter:
 main:
     ADDI64 r254, r254, -18d
     ST r31, r254, 2a, 16h
-    LI64 r1, 10d
+    LI8 r1, 10b
     ADDI64 r3, r254, 0d
     ST r1, r254, 0a, 1h
     ST r1, r254, 1a, 1h
@@ -50,6 +50,6 @@ main:
     LD r31, r254, 2a, 16h
     ADDI64 r254, r254, 18d
     JALA r0, r31, 0a
-code size: 382
+code size: 375
 ret: 0
 status: Ok(())
diff --git a/lang/tests/son_tests_struct_return_from_module_function.txt b/lang/tests/son_tests_struct_return_from_module_function.txt
index f0fa334..cf37ae2 100644
--- a/lang/tests/son_tests_struct_return_from_module_function.txt
+++ b/lang/tests/son_tests_struct_return_from_module_function.txt
@@ -1,6 +1,6 @@
 foo:
     ADDI64 r254, r254, -16d
-    LI64 r3, 2d
+    LI32 r3, 2w
     LI64 r5, 3d
     ADDI64 r4, r254, 0d
     ST r5, r254, 0a, 8h
@@ -33,6 +33,6 @@ main:
     LD r31, r254, 48a, 8h
     ADDI64 r254, r254, 56d
     JALA r0, r31, 0a
-code size: 359
+code size: 355
 ret: 0
 status: Ok(())
diff --git a/lang/tests/son_tests_tests_ptr_to_ptr_copy.txt b/lang/tests/son_tests_tests_ptr_to_ptr_copy.txt
index 0c9f616..ce6a245 100644
--- a/lang/tests/son_tests_tests_ptr_to_ptr_copy.txt
+++ b/lang/tests/son_tests_tests_ptr_to_ptr_copy.txt
@@ -1,6 +1,6 @@
 main:
     ADDI64 r254, r254, -10240d
-    LI64 r6, 64d
+    LI8 r6, 64b
     LI64 r7, 1024d
     LI64 r9, 1d
     LI64 r8, 0d
@@ -25,6 +25,6 @@ main:
     JMP :4
  2: ADDI64 r254, r254, 10240d
     JALA r0, r31, 0a
-code size: 205
+code size: 198
 ret: 64
 status: Ok(())
diff --git a/lang/tests/son_tests_wide_ret.txt b/lang/tests/son_tests_wide_ret.txt
index 55cd32a..3b6709a 100644
--- a/lang/tests/son_tests_wide_ret.txt
+++ b/lang/tests/son_tests_wide_ret.txt
@@ -8,10 +8,10 @@ main:
     ST r1, r254, 16a, 16h
     ADDI64 r7, r254, 0d
     BMC r32, r7, 16h
-    LD r1, r254, 12a, 1h
+    LD r12, r254, 12a, 1h
     LD r11, r254, 3a, 1h
-    SUB8 r2, r11, r1
-    ANDI r1, r2, 255d
+    SUB8 r3, r11, r12
+    ANDI r1, r3, 255d
     LD r31, r254, 32a, 16h
     ADDI64 r254, r254, 48d
     JALA r0, r31, 0a
@@ -21,9 +21,9 @@ maina:
     ADDI64 r32, r254, 36d
     JAL r31, r0, :small_struct
     ST r1, r254, 36a, 4h
-    LI64 r2, 1d
-    LI64 r3, 3d
-    LI64 r1, 0d
+    LI8 r2, 1b
+    LI8 r3, 3b
+    LI8 r1, 0b
     ADDI64 r6, r254, 0d
     ADDI64 r8, r6, 8d
     ADDI64 r7, r254, 16d
@@ -47,13 +47,13 @@ maina:
     JALA r0, r31, 0a
 small_struct:
     ADDI64 r254, r254, -4d
-    LI64 r2, 0d
+    LI16 r2, 0h
     ADDI64 r3, r254, 0d
     ST r2, r254, 0a, 2h
     ST r2, r254, 2a, 2h
     LD r1, r3, 0a, 4h
     ADDI64 r254, r254, 4d
     JALA r0, r31, 0a
-code size: 573
+code size: 546
 ret: 2
 status: Ok(())