diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index ba6c596..f8c4a8e 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -16,20 +16,15 @@ env:
 jobs:
   build:
     runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        features:
-          - --no-default-features
-          - --features async
     steps:
     - uses: dtolnay/rust-toolchain@master
       with:
-        toolchain: nightly-2023-10-21
+        toolchain: stable
         components: clippy
     - uses: actions/checkout@v3
     - name: Build
-      run: cargo build ${{ matrix.features }}
+      run: cargo build
     - name: Clippy
-      run: cargo clippy ${{ matrix.features }}
+      run: cargo clippy
     - name: Run tests
-      run: cargo test ${{ matrix.features }}
+      run: cargo test
diff --git a/Cargo.toml b/Cargo.toml
index bb15f71..bdd0474 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "buffered-io"
-version = "0.4.3"
+version = "0.5.0"
 edition = "2021"
 description = "Bufferering types for embedded-io"
 readme = "README.md"
@@ -10,12 +10,9 @@ license = "MIT / Apache-2.0"
 keywords = ["embedded", "buffer", "embedded-io", "read", "write"]
 exclude = [".github"]
 
-[features]
-async = ["embedded-io-async"]
-
 [dependencies]
 embedded-io = { version = "0.6" }
-embedded-io-async = { version = "0.6", optional = true }
+embedded-io-async = { version = "0.6" }
 
 [dev-dependencies]
 embedded-io-async = { version = "0.6", features = ["std"] }
diff --git a/rust-toolchain b/rust-toolchain
deleted file mode 100644
index 4cb3e45..0000000
--- a/rust-toolchain
+++ /dev/null
@@ -1 +0,0 @@
-nightly-2023-10-21
\ No newline at end of file
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
new file mode 100644
index 0000000..bdb08b3
--- /dev/null
+++ b/rust-toolchain.toml
@@ -0,0 +1,3 @@
+[toolchain]
+channel = "1.75"
+components = ["clippy"]
diff --git a/src/lib.rs b/src/lib.rs
index 87dd886..e711e28 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,8 +1,3 @@
 #![doc = include_str!("../README.md")]
 #![cfg_attr(not(test), no_std)]
-#![feature(impl_trait_projections)]
-#![feature(async_fn_in_trait)]
-#![allow(stable_features, unknown_lints, async_fn_in_trait)]
-
-#[cfg(feature = "async")]
 pub mod asynch;