diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6d4302c..8926339 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -33,11 +33,11 @@ jobs:
     - name: Build
       run: cargo build
       env:
-        RUST_FLAGS: -Dwarnings
+        RUSTFLAGS: -Dwarnings
     - name: Lint
       run: cargo clippy --all-targets --all-features
       env:
-        RUST_FLAGS: -Dwarnings
+        RUSTFLAGS: -Dwarnings
     - name: Install runtime system dependencies
       run: |
         sudo apt-get update
diff --git a/src/pull.rs b/src/pull.rs
index 184a7e8..d59698a 100644
--- a/src/pull.rs
+++ b/src/pull.rs
@@ -428,7 +428,7 @@ mod tests {
 
         // For determinism, we require for tests that either a distro or series is specified,
         // as no distribution would mean fallback to system distro
-        assert!(dist != None || series != None);
+        assert!(dist.is_some() || series.is_some());
 
         // Use a temp directory as working directory
         let temp_dir = tempfile::tempdir().unwrap();