diff --git a/.github/workflows/run.yaml b/.github/workflows/run.yaml
index 95b409f..fa375cb 100644
--- a/.github/workflows/run.yaml
+++ b/.github/workflows/run.yaml
@@ -30,7 +30,7 @@ jobs:
 
       - name: Run cargo build
         run: |
-          cargo build --release
+          cargo build --profile release-lto
         env:
           RUSTFLAGS: "-C target-cpu=native"
 
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index 29e8813..4c94d59 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2023-07-20"
+channel = "nightly-2023-12-05"
 components = [ "rustfmt", "clippy" ]
diff --git a/src/aoc2022/day17.rs b/src/aoc2022/day17.rs
index 90e31d5..c7b6c10 100644
--- a/src/aoc2022/day17.rs
+++ b/src/aoc2022/day17.rs
@@ -58,7 +58,7 @@ fn set(v: &mut Vec<bool>, index: usize) {
     v[index] = true;
 }
 
-fn get(v: &Vec<bool>, index: usize) -> bool {
+fn get(v: &[bool], index: usize) -> bool {
     if index >= v.len() {
         false
     } else {
diff --git a/src/aoc2022/day18.rs b/src/aoc2022/day18.rs
index 5d53bf3..4489db1 100644
--- a/src/aoc2022/day18.rs
+++ b/src/aoc2022/day18.rs
@@ -83,7 +83,7 @@ fn neighbors(
     z: usize,
     width: usize,
 ) -> impl Iterator<Item = (usize, usize, usize)> {
-    std::iter::from_generator(move || {
+    std::iter::from_coroutine(move || {
         if x > 0 {
             yield (x - 1, y, z);
         }
diff --git a/src/aoc2022/day19.rs b/src/aoc2022/day19.rs
index fd97bc6..d66e3c4 100644
--- a/src/aoc2022/day19.rs
+++ b/src/aoc2022/day19.rs
@@ -237,7 +237,7 @@ impl State {
         let min_use = bp.min_use;
         let max_use = bp.max_use;
 
-        std::iter::from_generator(move || {
+        std::iter::from_coroutine(move || {
             // not buying
             let mut ns = self;
             ns.collect();
diff --git a/src/aoc2022/grid.rs b/src/aoc2022/grid.rs
index 718688a..7b1d6f6 100644
--- a/src/aoc2022/grid.rs
+++ b/src/aoc2022/grid.rs
@@ -63,7 +63,7 @@ impl<T> Grid<T> {
     pub fn get_neighbors(&self, x: usize, y: usize) -> impl Iterator<Item = (usize, usize)> {
         let width = self.width;
         let height = self.height;
-        std::iter::from_generator(move || {
+        std::iter::from_coroutine(move || {
             if x != 0 {
                 yield (x - 1, y);
             }
diff --git a/src/aoc2023/day3.rs b/src/aoc2023/day3.rs
index 64199c3..6df34a9 100644
--- a/src/aoc2023/day3.rs
+++ b/src/aoc2023/day3.rs
@@ -36,7 +36,7 @@ impl Entry {
         &'a self,
         grid: &'b Grid<u8>,
     ) -> impl Iterator<Item = (usize, usize)> + 'b {
-        std::iter::from_generator(move || {
+        std::iter::from_coroutine(move || {
             let x = self.x as i32;
             let y = self.y as i32;
             let len = self.len as i32;
@@ -61,7 +61,7 @@ impl Entry {
 
 #[inline]
 fn get_entries(input: &Grid<u8>) -> impl Iterator<Item = Entry> + '_ {
-    std::iter::from_generator(move || {
+    std::iter::from_coroutine(move || {
         let mut current = None;
         for y in 0..input.height {
             for x in 0..input.width {
diff --git a/src/main.rs b/src/main.rs
index 75bddc3..664acc9 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,8 +1,8 @@
 #![feature(iter_array_chunks)]
 #![feature(array_windows)]
 #![feature(get_many_mut)]
-#![feature(generators)]
-#![feature(iter_from_generator)]
+#![feature(coroutines)]
+#![feature(iter_from_coroutine)]
 
 use std::time::Duration;