diff --git a/rtic-macros/src/syntax/analyze.rs b/rtic-macros/src/syntax/analyze.rs
index 57f9f2cdaf..3e5e80bd76 100644
--- a/rtic-macros/src/syntax/analyze.rs
+++ b/rtic-macros/src/syntax/analyze.rs
@@ -193,7 +193,7 @@ pub(crate) fn app(app: &App) -> Result<Analysis, syn::Error> {
 
     // Collect errors if any and return/halt
     if !error.is_empty() {
-        let mut err = error.get(0).unwrap().clone();
+        let mut err = error.first().unwrap().clone();
         error.iter().for_each(|e| err.combine(e.clone()));
         return Err(err);
     }
diff --git a/rtic-monotonics/src/lib.rs b/rtic-monotonics/src/lib.rs
index b34f9d6259..8757eb8595 100644
--- a/rtic-monotonics/src/lib.rs
+++ b/rtic-monotonics/src/lib.rs
@@ -23,7 +23,6 @@
 #![no_std]
 #![deny(missing_docs)]
 #![allow(incomplete_features)]
-#![feature(async_fn_in_trait)]
 #![cfg_attr(docsrs, feature(doc_cfg))]
 
 pub use rtic_time::{Monotonic, TimeoutError, TimerQueue};
diff --git a/rtic-time/src/lib.rs b/rtic-time/src/lib.rs
index 05c502605f..0c3e349580 100644
--- a/rtic-time/src/lib.rs
+++ b/rtic-time/src/lib.rs
@@ -6,7 +6,6 @@
 #![no_std]
 #![deny(missing_docs)]
 #![allow(incomplete_features)]
-#![feature(async_fn_in_trait)]
 
 use core::future::{poll_fn, Future};
 use core::pin::Pin;
diff --git a/rtic/src/export/cortex_basepri.rs b/rtic/src/export/cortex_basepri.rs
index e40ece4f3f..14017543d1 100644
--- a/rtic/src/export/cortex_basepri.rs
+++ b/rtic/src/export/cortex_basepri.rs
@@ -3,7 +3,7 @@ use cortex_m::register::basepri;
 pub use cortex_m::{
     asm::wfi,
     interrupt,
-    peripheral::{scb::SystemHandler, DWT, NVIC, SCB, SYST},
+    peripheral::{scb::SystemHandler, DWT, SCB, SYST},
     Peripherals,
 };
 
diff --git a/xtask/src/main.rs b/xtask/src/main.rs
index 30c3da0503..90ba13fbe7 100644
--- a/xtask/src/main.rs
+++ b/xtask/src/main.rs
@@ -23,7 +23,7 @@ pub struct Target<'a> {
 }
 
 impl<'a> Target<'a> {
-    const DEFAULT_FEATURES: &str = "test-critical-section";
+    const DEFAULT_FEATURES: &'static str = "test-critical-section";
 
     pub const fn new(triple: &'a str, has_std: bool) -> Self {
         Self { triple, has_std }