diff --git a/Cargo.toml b/Cargo.toml
index 1855224..efbc275 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -50,7 +50,7 @@ napi = { version = "2.16", features = ["full"], optional = true }
 napi-derive = { version="2.16",  optional = true}
 
 # glue (python)
-pyo3 = { version = "0.22", features = ["extension-module", "experimental-async"], optional = true}
+pyo3 = { version = "0.22", features = ["extension-module", "abi3-py38"], optional = true}
 
 # extra
 async-trait = { version = "0.1", optional = true }
diff --git a/dist/py/pyproject.toml b/dist/py/pyproject.toml
index 98a8bd4..f059255 100644
--- a/dist/py/pyproject.toml
+++ b/dist/py/pyproject.toml
@@ -1,18 +1,18 @@
 [project]
 name = "codemp"
-version = "0.0.1"
+version = "0.0.5"
 description = "code multiplexer"
-requires-python = ">=3.8"
+requires-python = ">= 3.8"
 license = "GPL-3.0-only"
 keywords = ["codemp", "cooperative", "rust", "python"]
 authors = [
-	{ name = "Camillo Schenone", email = "cschen@codemp.dev" },
+	{ name = "cschen", email = "cschen@codemp.dev" },
 	{ name = "alemi", email = "me@alemi.dev" },
 	{ name = "zaaarf", email = "me@zaaarf.foo" },
 	{ name = "frelodev", email = "frelodev@gmail.com" },
 ]
 maintainers = [
-	{ name = "Camillo Schenone", email = "cschen@codemp.dev" },
+	{ name = "cschen", email = "cschen@codemp.dev" },
 ]
 classifiers = [
 	"Programming Language :: Python"
diff --git a/src/ffi/python/controllers.rs b/src/ffi/python/controllers.rs
index 08c09ce..580cb02 100644
--- a/src/ffi/python/controllers.rs
+++ b/src/ffi/python/controllers.rs
@@ -3,8 +3,8 @@ use crate::api::Cursor;
 use crate::api::TextChange;
 use crate::buffer::Controller as BufferController;
 use crate::cursor::Controller as CursorController;
+use pyo3::exceptions::PyValueError;
 use pyo3::prelude::*;
-use pyo3::types::PyFunction;
 
 use super::Promise;
 use crate::a_sync_allow_threads;
@@ -49,15 +49,18 @@ impl CursorController {
 	}
 
 	#[pyo3(name = "callback")]
-	fn pycallback(&self, py: Python, cb: Py<PyFunction>) {
-		py.allow_threads(move || {
-			self.callback(move |ctl| {
-				Python::with_gil(|py| {
-					// TODO what to do with this error?
-					let _ = cb.call1(py, (ctl,));
-				})
+	fn pycallback(&self, py: Python, cb: PyObject) -> PyResult<()> {
+		if !cb.bind_borrowed(py).is_callable() {
+			return Err(PyValueError::new_err("The object passed must be callable."));
+		}
+
+		self.callback(move |ctl| {
+			Python::with_gil(|py| {
+				// TODO what to do with this error?
+				let _ = cb.call1(py, (ctl,));
 			})
-		})
+		});
+		Ok(())
 	}
 
 	#[pyo3(name = "clear_callback")]
@@ -116,15 +119,18 @@ impl BufferController {
 	}
 
 	#[pyo3(name = "callback")]
-	fn pycallback(&self, py: Python, cb: Py<PyFunction>) {
-		py.allow_threads(move || {
-			self.callback(move |ctl| {
-				Python::with_gil(|py| {
-					// TODO what to do with this error?
-					let _ = cb.call1(py, (ctl,));
-				})
+	fn pycallback(&self, py: Python, cb: PyObject) -> PyResult<()> {
+		if !cb.bind_borrowed(py).is_callable() {
+			return Err(PyValueError::new_err("The object passed must be callable."));
+		}
+
+		self.callback(move |ctl| {
+			Python::with_gil(|py| {
+				// TODO what to do with this error?
+				let _ = cb.call1(py, (ctl,));
 			})
-		})
+		});
+		Ok(())
 	}
 
 	#[pyo3(name = "clear_callback")]
diff --git a/src/ffi/python/mod.rs b/src/ffi/python/mod.rs
index 088b556..9833663 100644
--- a/src/ffi/python/mod.rs
+++ b/src/ffi/python/mod.rs
@@ -13,11 +13,8 @@ use crate::{
 	Client, Workspace,
 };
 
+use pyo3::exceptions::{PyConnectionError, PyRuntimeError, PySystemError};
 use pyo3::prelude::*;
-use pyo3::{
-	exceptions::{PyConnectionError, PyRuntimeError, PySystemError},
-	types::PyFunction,
-};
 
 use std::sync::OnceLock;
 use tokio::sync::{mpsc, oneshot};
@@ -158,7 +155,10 @@ fn connect(host: String, username: String, password: String) -> PyResult<Promise
 }
 
 #[pyfunction]
-fn set_logger(logging_cb: Py<PyFunction>, debug: bool) -> bool {
+fn set_logger(py: Python, logging_cb: PyObject, debug: bool) -> bool {
+	if !logging_cb.bind_borrowed(py).is_callable() {
+		return false;
+	}
 	let (tx, mut rx) = mpsc::unbounded_channel();
 	let level = if debug {
 		tracing::Level::DEBUG