diff --git a/src/compiler.rs b/src/compiler.rs
index 6d07bef..4df31e2 100644
--- a/src/compiler.rs
+++ b/src/compiler.rs
@@ -33,6 +33,7 @@ pub enum Op {
     MatchWord,
     PanicIfNoMatch,
     MatchConstant,
+    MatchType,
     MatchTuple,
     PushTuple,
     LoadTuple,
@@ -140,6 +141,7 @@ impl std::fmt::Display for Op {
             ResetMatch => "reset_match",
             PanicIfNoMatch => "panic_if_no_match",
             MatchConstant => "match_constant",
+            MatchType => "match_type",
             MatchTuple => "match_tuple",
             PushTuple => "push_tuple",
             LoadTuple => "load_tuple",
@@ -210,7 +212,7 @@ impl Chunk {
             | PanicIfNoMatch | MatchWord | ResetMatch | GetKey | PanicNoWhen | PanicNoMatch
             | TypeOf | Duplicate | Decrement | Truncate | Noop | LoadTuple | LoadList | Eq
             | Add | Sub | Mult | Div | Unbox | BoxStore | Assert | Get | At | Not | Panic
-            | EmptyString | ConcatStrings | Stringify => {
+            | EmptyString | ConcatStrings | Stringify | MatchType => {
                 println!("{i:04}: {op}")
             }
             Constant | MatchConstant => {
@@ -359,10 +361,12 @@ impl Compiler {
             )
         }
         self.chunk.constants.push(val);
-        self.chunk.bytecode.push(Op::Constant as u8);
-        self.spans.push(self.span);
-        self.chunk.bytecode.push(constant_index as u8);
-        self.spans.push(self.span);
+        self.emit_op(Op::Constant);
+        // self.chunk.bytecode.push(Op::Constant as u8);
+        // self.spans.push(self.span);
+        self.emit_byte(constant_index);
+        // self.chunk.bytecode.push(constant_index as u8);
+        // self.spans.push(self.span);
         self.stack_depth += 1;
     }
 
@@ -380,10 +384,12 @@ impl Compiler {
         if constant_index == self.chunk.constants.len() {
             self.chunk.constants.push(val);
         }
-        self.chunk.bytecode.push(Op::MatchConstant as u8);
-        self.spans.push(self.span);
-        self.chunk.bytecode.push(constant_index as u8);
-        self.spans.push(self.span);
+        self.emit_op(Op::MatchConstant);
+        self.emit_byte(constant_index);
+        // self.chunk.bytecode.push(Op::MatchConstant as u8);
+        // self.spans.push(self.span);
+        // self.chunk.bytecode.push(constant_index as u8);
+        // self.spans.push(self.span);
     }
 
     fn emit_op(&mut self, op: Op) {
@@ -572,6 +578,12 @@ impl Compiler {
                 }
                 self.match_constant(Value::Keyword(kw_index));
             }
+            AsPattern(word, typ) => {
+                self.emit_constant(self.chunk.kw_from(typ).unwrap());
+                self.emit_op(Op::MatchType);
+                self.stack_depth -= 1;
+                self.bind(word);
+            }
             StringPattern(s) => {
                 let existing_str = self.chunk.strings.iter().position(|e| e == s);
                 let str_index = match existing_str {
@@ -1142,7 +1154,6 @@ impl Compiler {
             | Do(..)
             | Splat(..)
             | InterpolatedPattern(..)
-            | AsPattern(..)
             | Splattern(..) => todo!(),
             And | Or => unreachable!(),
         }
@@ -1160,7 +1171,7 @@ impl Compiler {
                 | MatchFalse | MatchWord | ResetMatch | PanicIfNoMatch | GetKey | PanicNoWhen
                 | PanicNoMatch | TypeOf | Duplicate | Truncate | Decrement | LoadTuple
                 | LoadList | Eq | Add | Sub | Mult | Div | Unbox | BoxStore | Assert | Get | At
-                | Not | Panic | EmptyString | ConcatStrings | Stringify => {
+                | Not | Panic | EmptyString | ConcatStrings | Stringify | MatchType => {
                     println!("{i:04}: {op}")
                 }
                 Constant | MatchConstant => {
diff --git a/src/main.rs b/src/main.rs
index 770a628..34bbed9 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -74,10 +74,8 @@ pub fn run(src: &'static str) {
 pub fn main() {
     env::set_var("RUST_BACKTRACE", "1");
     let src = "
-let x = 42
-let y = :foo
-let z = \"thing\"
-\"{x} {y} {z}\"
+let (x as :keyword, y as :number) = (:ok, 42)
+[x, y]
     ";
     run(src);
 }
diff --git a/src/vm.rs b/src/vm.rs
index ca6088d..405ada7 100644
--- a/src/vm.rs
+++ b/src/vm.rs
@@ -249,6 +249,15 @@ impl<'a> Vm<'a> {
                 self.matches = true;
                 self.ip += 1;
             }
+            MatchType => {
+                let as_type = self.pop();
+                let idx = self.stack.len() - self.match_depth as usize - 1;
+                let val_type = self.stack[idx].type_of();
+                let val_type = self.chunk.kw_from(val_type).unwrap();
+                self.matches = val_type == as_type;
+                self.ip += 1;
+                self.interpret()
+            }
             MatchNil => {
                 let idx = self.stack.len() - self.match_depth as usize - 1;
                 if self.stack[idx] == Value::Nil {
@@ -579,14 +588,15 @@ impl<'a> Vm<'a> {
                 self.push(Value::String(Rc::new("".to_string())));
                 self.ip += 1;
             }
+            //TODO: don't use the schlemiel's algo here
             ConcatStrings => {
                 let second = self.pop();
                 let first = self.pop();
                 let combined = match (first, second) {
                     (Value::String(first), Value::String(second)) => {
-                        let mut newstr = first.as_ref().clone();
-                        newstr.push_str(second.as_str());
-                        Value::String(Rc::new(newstr))
+                        let mut new = first.as_ref().clone();
+                        new.push_str(second.as_str());
+                        Value::String(Rc::new(new))
                     }
                     _ => unreachable!(),
                 };