diff --git a/CHANGELOG.md b/CHANGELOG.md
index c90b7c0b..bc77d936 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ## [Unreleased]
 
 - [#710]: Update CI
+- [#707]: `defmt-rtt`: Use `atomic-polyfill`
 - [#706]: Satisfy clippy
 - [#704]: Release `defmt-macros 0.3.3`, `defmt-print 0.3.3`, `defmt-rtt 0.4.0`
 - [#703]: `defmt-print`: Update to `clap 4.0`.
@@ -27,6 +28,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - [#678]: Satisfy clippy
 
 [#710]: https://github.com/knurling-rs/defmt/pull/710
+[#707]: https://github.com/knurling-rs/defmt/pull/707
 [#706]: https://github.com/knurling-rs/defmt/pull/706
 [#704]: https://github.com/knurling-rs/defmt/pull/704
 [#703]: https://github.com/knurling-rs/defmt/pull/703
diff --git a/firmware/defmt-rtt/Cargo.toml b/firmware/defmt-rtt/Cargo.toml
index 0b97c3c8..13e7c9cf 100644
--- a/firmware/defmt-rtt/Cargo.toml
+++ b/firmware/defmt-rtt/Cargo.toml
@@ -11,5 +11,6 @@ repository = "https://github.com/knurling-rs/defmt"
 version = "0.4.0"
 
 [dependencies]
+atomic-polyfill = "1"
 defmt = { version = "0.3", path = "../../defmt" }
 critical-section = "1.1"
diff --git a/firmware/defmt-rtt/src/channel.rs b/firmware/defmt-rtt/src/channel.rs
index 552f1e5d..c82be867 100644
--- a/firmware/defmt-rtt/src/channel.rs
+++ b/firmware/defmt-rtt/src/channel.rs
@@ -1,7 +1,6 @@
-use core::{
-    ptr,
-    sync::atomic::{AtomicUsize, Ordering},
-};
+use core::ptr;
+
+use atomic_polyfill::{AtomicUsize, Ordering};
 
 use crate::{consts::BUF_SIZE, MODE_BLOCK_IF_FULL, MODE_MASK};
 
diff --git a/firmware/defmt-rtt/src/lib.rs b/firmware/defmt-rtt/src/lib.rs
index c81c4709..69bbcaa5 100644
--- a/firmware/defmt-rtt/src/lib.rs
+++ b/firmware/defmt-rtt/src/lib.rs
@@ -36,7 +36,7 @@
 mod channel;
 mod consts;
 
-use core::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
+use atomic_polyfill::{AtomicBool, AtomicUsize, Ordering};
 
 use crate::{channel::Channel, consts::BUF_SIZE};