diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 27e1f98..beeec7f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -5,6 +5,9 @@ on:
      branches:
        - main
 
+env:
+  RUST_TOOLCHAIN: "1.90"
+
 # This workflow runs on pull requests to the main branch
 # It builds the project for 2 platforms, Linux arm64 and macOS arm64,
 # and runs tests for each platform. All platforms tested on merge to main
@@ -16,7 +19,7 @@ jobs:
        - uses: actions/checkout@v4
        - uses: actions-rs/toolchain@v1
          with:
-           toolchain: 1.88.0
+           toolchain: ${{ env.RUST_TOOLCHAIN }}
            profile: minimal
            override: true
        - uses: swatinem/rust-cache@v2
@@ -34,7 +37,7 @@ jobs:
        - uses: actions/checkout@v4
        - uses: actions-rs/toolchain@v1
          with:
-           toolchain: 1.88.0
+           toolchain: ${{ env.RUST_TOOLCHAIN }}
            profile: minimal
            override: true
        - uses: swatinem/rust-cache@v2
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index abe38f9..4debe1d 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -4,6 +4,8 @@ on:
   push:
     branches:
       - main
+env:
+  RUST_TOOLCHAIN: "1.90"
 
 jobs:
   # ──────────────── Linux (via Makefile) ────────────────
@@ -15,7 +17,7 @@ jobs:
 
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.88.0
+          toolchain: ${{ env.RUST_TOOLCHAIN }}
           profile: minimal
           override: true
 
@@ -69,7 +71,7 @@ jobs:
 
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.88.0
+          toolchain: ${{ env.RUST_TOOLCHAIN }}
           profile: minimal
           override: true
 
@@ -123,7 +125,7 @@ jobs:
 
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.88.0
+          toolchain: ${{ env.RUST_TOOLCHAIN }}
           profile: minimal
           override: true
 
@@ -154,7 +156,7 @@ jobs:
 
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.88.0
+          toolchain: ${{ env.RUST_TOOLCHAIN }}
           profile: minimal
           override: true
 
@@ -185,7 +187,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.88.0
+          toolchain: ${{ env.RUST_TOOLCHAIN }}
           profile: minimal
           override: true