Update CI

.github/workflows/ci.yml

@@ -28,3 +28,14 @@ jobs:
         run: cargo build --all --verbose
       - name: Run tests
         run: cargo test --all --verbose
+
+      # build on nightly
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: nightly
+          override: true
+          components: clippy, rustfmt
+      - name: Build on nightly without features
+        run: cargo build --no-default-features
+      - name: Build on nightly
+        run: cargo build --all --verbose