diff --git a/src/lib.rs b/src/lib.rs
index ab7f48b..9f887ce 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,17 +1,93 @@
-use nvim_oxi as oxi;
-use oxi::{api::{opts::CreateCommandOpts, types::{CommandNArgs, CommandArgs}}, libuv::AsyncHandle};
+use std::collections::BTreeMap;
 
-use codemp::{prelude::*, Controller, tokio::sync::mpsc, errors::IgnorableError};
+use nvim_oxi as oxi;
+use oxi::{api::{opts::{CreateCommandOpts, CreateAugroupOpts, CreateAutocmdOpts, GetTextOpts}, types::{CommandNArgs, CommandArgs}, Buffer}, libuv::AsyncHandle};
+
+use codemp::{prelude::*, Controller, tokio::sync::mpsc, errors::IgnorableError, proto::{RowCol, CursorEvent}, buffer::factory::OperationFactory};
 use codemp::instance::RUNTIME;
 
+#[derive(Default)]
+struct CursorStorage {
+	storage: BTreeMap<String, u32>
+}
+
+fn multiline_hl(buf: &mut Buffer, namespace: u32, hl: &str, start: RowCol, end: RowCol) -> oxi::Result<()> {
+	for i in start.row..=end.row {
+		if i == start.row && i == end.row {
+			buf.add_highlight(namespace, hl, i as usize, (start.col as usize)..=(end.col as usize))?;
+		} else if i == start.row {
+			buf.add_highlight(namespace, hl, i as usize, (start.col as usize)..)?;
+		} else if i == end.row {
+			buf.add_highlight(namespace, hl, i as usize, 0..=(end.col as usize))?;
+		} else {
+			buf.add_highlight(namespace, hl, i as usize, 0..)?;
+		}
+	}
+
+	Ok(())
+}
+
+fn byte2rowcol(buf: &Buffer, index: usize) -> RowCol {
+	buf.get_offset(index)
+	
+	oxi::api::
+}
+
+fn multiline_set_text(buf: &mut Buffer, change: CodempTextChange) -> oxi::Result<()> {
+	for i in change.span
+
+
+	Ok(())
+}
+
+fn cursor_position() -> oxi::Result<CodempCursorPosition> {
+	let buf = oxi::api::get_current_buf().get_name()?;
+	let cur = oxi::api::get_current_win().get_cursor()?;
+	Ok(CodempCursorPosition {
+		buffer: buf.to_str().unwrap_or("").to_string(),
+		start: Some(RowCol { row: cur.0 as i32, col: cur.1 as i32 }),
+		end: Some(RowCol { row: cur.0 as i32, col: cur.1 as i32 +1 }),
+	})
+}
+
+fn buffer_content(buf: &Buffer) -> oxi::Result<String> {
+	let mut out = String::new();
+	for line in buf.get_text(0.., 0, 0, &GetTextOpts::default())? {
+		out.push_str(&line.to_string_lossy());
+		out.push('\n');
+	}
+	Ok(out)
+}
+
+impl CursorStorage {
+	pub fn update(&mut self, user: &str, pos: Option<CodempCursorPosition>) -> oxi::Result<()> {
+		let mut buf = oxi::api::get_current_buf();
+
+		if let Some(prev) = self.storage.get(user) {
+			buf.clear_namespace(*prev, 0..)?;
+		}
+
+		if let Some(position) = pos {
+			let namespace = oxi::api::create_namespace(user);
+			// TODO don't hardcode highlight color but create one for each user
+			multiline_hl(&mut buf, namespace, "ErrorMsg", position.start(), position.end())?;
+			self.storage.insert(user.into(), namespace);
+		}
+
+		Ok(())
+	}
+}
+
 #[oxi::module]
 fn api() -> oxi::Result<()> {
 	oxi::api::create_user_command(
 		"Connect",
 		|args: CommandArgs| {
 			let addr = args.args.unwrap_or("http://alemi.dev:50051".into());
+
 			RUNTIME.block_on(CODEMP_INSTANCE.connect(&addr))
 				.map_err(|e| nvim_oxi::api::Error::Other(format!("xx could not connect: {}", e)))?;
+
 			oxi::print!("++ connected to {}", addr);
 			Ok(())
 		},
@@ -25,19 +101,39 @@ fn api() -> oxi::Result<()> {
 		"Join",
 		|args: CommandArgs| {
 			let workspace = args.args.expect("one arg required but not provided");
+
 			let controller = RUNTIME.block_on(CODEMP_INSTANCE.join(&workspace))
 				.map_err(|e| nvim_oxi::api::Error::Other(format!("xx could not join: {}", e)))?;
-			let (tx, mut rx) = mpsc::unbounded_channel();
+
+			let (tx, mut rx) = mpsc::unbounded_channel::<CursorEvent>();
+			let mut container = CursorStorage::default();
+
 			let handle = AsyncHandle::new(move || {
 				while let Ok(x) = rx.try_recv() { // TODO do this inside oxi::schedule() to not block vim
-					oxi::print!("cursor: {:?}", x);
+					container.update(&x.user, x.position)?;
 				}
 				Ok::<_, oxi::Error>(())
 			}).map_err(|e| oxi::api::Error::Other(format!("xx could not create handle: {}", e)))?;
-			controller.callback(move |x| {
+
+			controller.clone().callback(move |x| {
 				tx.send(x).unwrap_or_warn("could not enqueue callback");
 				handle.send().unwrap_or_warn("could not wake async handle");
 			});
+
+			let au = oxi::api::create_augroup(&workspace, &CreateAugroupOpts::builder().clear(true).build())?;
+			oxi::api::create_autocmd(
+			[ "CursorMovedI", "CursorMoved", "CompleteDone", "InsertEnter", "InsertLeave" ],
+				&CreateAutocmdOpts::builder()
+					.group(au)
+					.desc("update cursor position")
+					.callback(move |_x| {
+						RUNTIME.block_on(controller.send(cursor_position()?))
+							.map_err(|e| oxi::api::Error::Other(format!("could not send cursor position: {}", e)))?;
+						Ok::<bool, oxi::Error>(true)
+					})
+					.build()
+			)?;
+
 			oxi::print!("++ joined workspace session '{}'", workspace);
 			Ok(())
 		},
@@ -51,8 +147,45 @@ fn api() -> oxi::Result<()> {
 		"Attach",
 		|args: CommandArgs| {
 			let buffer = args.args.expect("one arg required but not provided");
+
 			let controller = RUNTIME.block_on(CODEMP_INSTANCE.attach(&buffer))
 				.map_err(|e| nvim_oxi::api::Error::Other(format!("xx could not attach: {}", e)))?;
+
+			let buf = oxi::api::get_current_buf();
+			let (tx, mut rx) = mpsc::unbounded_channel::<CodempTextChange>();
+			// let mut container = CursorStorage::default();
+
+			let handle = AsyncHandle::new(move || {
+				while let Ok(x) = rx.try_recv() { // TODO do this inside oxi::schedule() to not block vim
+					buf.set_text(line_range, start_col, end_col, replacement)
+				}
+				Ok::<_, oxi::Error>(())
+			}).map_err(|e| oxi::api::Error::Other(format!("xx could not create handle: {}", e)))?;
+
+			controller.clone().callback(move |x| {
+				tx.send(x).unwrap_or_warn("could not enqueue callback");
+				handle.send().unwrap_or_warn("could not wake async handle");
+			});
+
+			let au = oxi::api::create_augroup(&buffer, &CreateAugroupOpts::builder().clear(true).build())?;
+			oxi::api::create_autocmd(
+			[ "CursorMovedI", "CursorMoved", "CompleteDone", "InsertEnter", "InsertLeave" ],
+				&CreateAutocmdOpts::builder()
+					.group(au)
+					.desc("update cursor position")
+					.callback(move |_x| {
+						if let Some(op) = controller.replace(&buffer_content(&buf)?) {
+							RUNTIME.block_on(controller.send(op))
+								.map_err(|e| oxi::api::Error::Other(format!("could not send cursor position: {}", e)))?;
+							Ok::<bool, oxi::Error>(true)
+						} else {
+							Ok::<bool, oxi::Error>(false)
+						}
+						
+					})
+					.build()
+			)?;
+
 			oxi::print!("++ attached to buffer '{}'", buffer);
 			Ok(())
 		},