diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..1125fd4
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,32 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  check:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install Nix
+        uses: DeterminateSystems/nix-installer-action@v17
+
+      - name: Enable Nix cache
+        uses: DeterminateSystems/magic-nix-cache-action@v8
+
+      - name: Build
+        run: nix develop --command cargo build
+
+      - name: Test
+        run: nix develop --command cargo test
+
+      - name: Clippy
+        run: nix develop --command cargo clippy -- -D warnings
diff --git a/README.md b/README.md
index 9ae4614..6957e20 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,8 @@
 # njalla-cli
 
+[![CI](https://github.com/orveth/njalla-cli/actions/workflows/ci.yml/badge.svg)](https://github.com/orveth/njalla-cli/actions/workflows/ci.yml)
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+
 Privacy-first domain management CLI for [Njalla](https://njal.la), built in Rust.
 
 > **Disclaimer:** This is an unofficial project and is not affiliated with or endorsed by Njalla. Use at your own risk. Always verify important operations through the official Njalla web interface.
diff --git a/src/client.rs b/src/client.rs
index 66d0e2b..a1f8ab8 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -88,7 +88,7 @@ impl NjallaClient {
         };
 
         if self.debug {
-            eprintln!("[DEBUG] Request: {} {:?}", method, params);
+            eprintln!("[DEBUG] Request: {method} {params:?}");
         }
 
         let response = self
@@ -102,7 +102,7 @@ impl NjallaClient {
         let response_text = response.text().await?;
 
         if self.debug {
-            eprintln!("[DEBUG] Response: {}", response_text);
+            eprintln!("[DEBUG] Response: {response_text}");
         }
 
         let api_response: ApiResponse<T> = serde_json::from_str(&response_text)?;
diff --git a/src/output.rs b/src/output.rs
index a4215fd..9524e6c 100644
--- a/src/output.rs
+++ b/src/output.rs
@@ -339,7 +339,7 @@ pub fn format_transactions(transactions: &[Transaction], format: OutputFormat) -
 
                 // Pad before coloring to avoid ANSI codes breaking alignment
                 let amount_raw = format!("€{}", t.amount);
-                let amount_padded = format!("{:<10}", amount_raw);
+                let amount_padded = format!("{amount_raw:<10}");
                 let amount_str = if t.completed.is_some() {
                     amount_padded.green().to_string()
                 } else {