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diff --git a/ocaml/lib/dill.ml b/ocaml/lib/dill.ml
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+(** Dill - Terminal I/O driver using Eio *)
+
+open Noun
+
+(** Belt event types (keyboard input) *)
+type belt =
+  | Aro of [`d | `l | `r | `u]  (* Arrow keys *)
+  | Bac                          (* Backspace *)
+  | Ctl of char                  (* Control-X *)
+  | Del                          (* Delete *)
+  | Met of char                  (* Meta/Alt-X *)
+  | Ret                          (* Return/Enter *)
+  | Txt of string list           (* Text input *)
+
+(** Blit event types (terminal output) *)
+type blit =
+  | Lin of string                (* Line of text *)
+  | Klr of noun                  (* Styled text *)
+  | Mor of blit list             (* Multiple blits *)
+  | Hop of int                   (* Cursor hop *)
+  | Clr                          (* Clear screen *)
+
+type effect = {
+  wire: noun;
+  blit: blit;
+}
+
+(** Render a blit to the terminal using Eio *)
+let rec render_blit ~stdout = function
+  | Lin text ->
+      Eio.Flow.copy_string (text ^ "\n") stdout
+  | Klr _styled ->
+      (* TODO: Parse styled text and convert to ANSI codes *)
+      Eio.Flow.copy_string "<styled text>\n" stdout
+  | Mor blits ->
+      List.iter (render_blit ~stdout) blits
+  | Hop n ->
+      (* ANSI cursor movement *)
+      let ansi = Printf.sprintf "\x1b[%dC" n in
+      Eio.Flow.copy_string ansi stdout
+  | Clr ->
+      (* ANSI clear screen and home cursor *)
+      Eio.Flow.copy_string "\x1b[2J\x1b[H" stdout
+
+(** Create a belt event noun from keyboard input *)
+let make_belt_event wire belt_type =
+  let belt_atom = match belt_type with
+    | Ret -> atom_of_string "ret"
+    | Bac -> atom_of_string "bac"
+    | Del -> atom_of_string "del"
+    | Aro `u -> cell (atom_of_string "aro") (atom_of_string "u")
+    | Aro `d -> cell (atom_of_string "aro") (atom_of_string "d")
+    | Aro `l -> cell (atom_of_string "aro") (atom_of_string "l")
+    | Aro `r -> cell (atom_of_string "aro") (atom_of_string "r")
+    | Ctl c -> cell (atom_of_string "ctl") (atom (Z.of_int (Char.code c)))
+    | Met c -> cell (atom_of_string "met") (atom (Z.of_int (Char.code c)))
+    | Txt strs ->
+        let rec build_list = function
+          | [] -> atom Z.zero
+          | s :: rest ->
+              (* Each string in the list becomes a character code *)
+              let code = if String.length s > 0 then Char.code s.[0] else 0 in
+              cell (atom (Z.of_int code)) (build_list rest)
+        in
+        cell (atom_of_string "txt") (build_list strs)
+  in
+  let card = cell (atom_of_string "belt") belt_atom in
+  cell wire card
+
+(** Parse line input into belt event *)
+let parse_input line =
+  if String.length line = 0 then
+    Ret
+  else if line = "\x7f" || line = "\x08" then
+    Bac
+  else if String.length line = 1 && Char.code line.[0] < 32 then
+    Ctl line.[0]
+  else
+    let char_list = String.to_seq line |> List.of_seq in
+    let str_list = List.map (String.make 1) char_list in
+    Txt str_list
+
+(** Run terminal input loop using Eio *)
+let input_loop ~stdin ~state ~wire process_effects =
+  let buf_read = Eio.Buf_read.of_flow stdin ~max_size:4096 in
+  let rec loop () =
+    (* Read a line from terminal *)
+    try
+      let line = Eio.Buf_read.line buf_read in
+      let belt = parse_input (String.trim line) in
+      let ovum = make_belt_event wire belt in
+
+      (* Poke Arvo with belt event *)
+      let result = State.poke state ovum in
+
+      (* Process effects *)
+      process_effects result;
+
+      loop ()
+    with End_of_file -> ()
+  in
+  loop ()
+
+(** Render effects to terminal *)
+let render_effects ~stdout effects_noun =
+
+  (* Parse effects and filter for Dill *)
+  let rec parse_effects_list = function
+    | Atom z when Z.equal z Z.zero -> []
+    | Cell (Cell (wire, card), rest) ->
+        (* Check if this is a Dill effect *)
+        let is_dill = match wire with
+          | Cell (Atom d, Cell (Atom term, _)) ->
+              Z.equal d (Z.of_int (Char.code 'd')) &&
+              Z.equal term (Z.of_string "0x6d726574")  (* 'term' *)
+          | _ -> false
+        in
+        if is_dill then
+          (wire, card) :: parse_effects_list rest
+        else
+          parse_effects_list rest
+    | _ -> []
+  in
+
+  let dill_effects = parse_effects_list effects_noun in
+
+  (* Render each blit *)
+  List.iter (fun (_wire, card) ->
+    match card with
+    | Cell (Atom tag, blit_noun) when Z.equal tag (Z.of_string "0x74696c62") (* 'blit' *) ->
+        (* Parse and render blit *)
+        let blit = match blit_noun with
+          | Cell (Atom lin_tag, Cell (Cell (_, text), _))
+            when Z.equal lin_tag (Z.of_string "0x6e696c") -> (* 'lin' *)
+              let str = match text with
+                | Atom z ->
+                    if Z.equal z Z.zero then ""
+                    else Z.to_bits z
+                | _ -> "(complex text)"
+              in
+              Lin str
+          | _ -> Lin "(unparsed blit)"
+        in
+        render_blit ~stdout blit
+    | _ -> ()
+  ) dill_effects