diff --git a/.github/workflows/check.yaml b/.github/workflows/check.yaml
index 6f59b6e..2ca16fb 100644
--- a/.github/workflows/check.yaml
+++ b/.github/workflows/check.yaml
@@ -20,7 +20,7 @@ jobs:
         uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          toolchain: 1.76.0
+          toolchain: 1.78.0
           components: rustfmt, clippy
           override: true
       - name: Check ✅
diff --git a/Earthfile b/Earthfile
index 3583c9e..c33ea16 100644
--- a/Earthfile
+++ b/Earthfile
@@ -17,9 +17,9 @@ docker:
   SAVE IMAGE --push fuwn/september:$tag
 
 deps:
-  ARG rustc="1.76.0"
+  ARG rustc="1.78.0"
 
-  FROM clux/muslrust:$rustc
+  FROM clux/muslrust:$rustc-stable
 
   RUN curl "https://static.rust-lang.org/rustup/archive/${RUSTUP_VER}/${RUST_ARCH}/rustup-init" -o rustup-init \
     && chmod +x rustup-init \