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diff --git a/ocaml/lib/io/dill.ml b/ocaml/lib/io/dill.ml
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+(* Dill - Terminal I/O Driver with Eio
+ *
+ * This is the terminal driver for ship console interaction.
+ * Uses Eio for async terminal I/O - non-blocking console operations!
+ *
+ * Key innovation vs C Vere:
+ * - C Vere: Blocking terminal I/O, single-threaded input processing
+ * - Overe: Async terminal I/O with Eio, concurrent input/output handling
+ *)
+
+(* Dill configuration *)
+type config = {
+  prompt: string;  (* Command prompt to display *)
+}
+
+(* Dill driver state *)
+type t = {
+  config: config;
+  mutable stats: stats;
+}
+
+and stats = {
+  mutable lines_read: int64;
+  mutable lines_written: int64;
+  mutable bytes_read: int64;
+  mutable bytes_written: int64;
+}
+
+(* Create Dill driver *)
+let create config = {
+  config;
+  stats = {
+    lines_read = 0L;
+    lines_written = 0L;
+    bytes_read = 0L;
+    bytes_written = 0L;
+  };
+}
+
+(* Write output to terminal *)
+let write_output dill ~env text =
+  let stdout = Eio.Stdenv.stdout env in
+
+  (* Async write - doesn't block! *)
+  Eio.Flow.copy_string text stdout;
+
+  dill.stats.lines_written <- Int64.succ dill.stats.lines_written;
+  dill.stats.bytes_written <- Int64.add dill.stats.bytes_written
+    (Int64.of_int (String.length text))
+
+(* Write prompt *)
+let write_prompt dill ~env =
+  write_output dill ~env (dill.config.prompt ^ " ")
+
+(* Read input line from terminal *)
+let read_input dill ~env =
+  let stdin = Eio.Stdenv.stdin env in
+
+  (* Read line - async, doesn't block other operations! *)
+  let buf = Buffer.create 256 in
+  let chunk = Cstruct.create 1 in
+
+  let rec read_until_newline () =
+    match Eio.Flow.single_read stdin chunk with
+    | 0 -> None  (* EOF *)
+    | _ ->
+        let char = Cstruct.get_char chunk 0 in
+        if char = '\n' then
+          Some (Buffer.contents buf)
+        else begin
+          Buffer.add_char buf char;
+          read_until_newline ()
+        end
+  in
+
+  match read_until_newline () with
+  | Some line ->
+      dill.stats.lines_read <- Int64.succ dill.stats.lines_read;
+      dill.stats.bytes_read <- Int64.add dill.stats.bytes_read
+        (Int64.of_int (String.length line));
+      Some line
+  | None -> None
+
+(* Input fiber - continuously reads terminal input *)
+let input_fiber dill ~env ~sw:_ ~event_stream =
+  Printf.printf "[Dill] Input fiber started\n%!";
+
+  let rec loop () =
+    try
+      (* Show prompt *)
+      write_prompt dill ~env;
+
+      (* Read input line - async! *)
+      (match read_input dill ~env with
+       | Some line ->
+           Printf.printf "[Dill] Read input: %s\n%!" line;
+
+           (* Create ovum for runtime *)
+           let ovum = Nock_lib.Effects.make_ovum
+             ~wire:(Nock_lib.Noun.atom 0)
+             ~card:(Nock_lib.Noun.cell
+                     (Nock_lib.Noun.atom 4)  (* dill tag *)
+                     (Nock_lib.Noun.atom 0))  (* simplified - would be parsed command *)
+           in
+
+           (* Send to runtime event queue *)
+           Eio.Stream.add event_stream ovum;
+
+           loop ()
+
+       | None ->
+           Printf.printf "[Dill] EOF on input\n%!"
+      )
+    with
+    | End_of_file ->
+        Printf.printf "[Dill] Input fiber closed\n%!"
+    | Eio.Cancel.Cancelled _ ->
+        Printf.printf "[Dill] Input fiber cancelled\n%!"
+  in
+
+  loop ()
+
+(* Output fiber - handles terminal output *)
+let output_fiber dill ~env ~sw:_ output_stream =
+  Printf.printf "[Dill] Output fiber started\n%!";
+
+  let rec loop () =
+    try
+      (* Wait for output from runtime *)
+      let text = Eio.Stream.take output_stream in
+
+      (* Write to terminal - async! *)
+      write_output dill ~env text;
+
+      loop ()
+    with
+    | End_of_file ->
+        Printf.printf "[Dill] Output fiber closed\n%!"
+    | Eio.Cancel.Cancelled _ ->
+        Printf.printf "[Dill] Output fiber cancelled\n%!"
+  in
+
+  loop ()
+
+(* Run Dill driver - spawns input and output fibers *)
+let run dill ~env ~sw ~event_stream =
+  Printf.printf "[Dill] Starting terminal driver\n%!";
+
+  (* Create output stream for terminal output *)
+  let output_stream = Eio.Stream.create 100 in
+
+  (* Spawn input fiber *)
+  Eio.Fiber.fork ~sw (fun () ->
+    input_fiber dill ~env ~sw ~event_stream
+  );
+
+  (* Spawn output fiber *)
+  Eio.Fiber.fork ~sw (fun () ->
+    output_fiber dill ~env ~sw output_stream
+  );
+
+  Printf.printf "[Dill] Terminal driver running!\n%!";
+
+  output_stream  (* Return output stream so runtime can send output *)
+
+(* Get statistics *)
+let get_stats dill = dill.stats