diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
new file mode 100644
index 0000000..178d5cb
--- /dev/null
+++ b/.github/workflows/checks.yml
@@ -0,0 +1,33 @@
+name: Code checks
+on:
+  pull_request:
+    branches: [ "main" ]
+jobs:
+  scalafmt-lint:
+    name: Scalafmt lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+      - uses: jrouly/scalafmt-native-action@v4
+
+  scalafix-lint:
+    name: Scalafix lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+
+      - name: Setup JDK
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: 21
+          cache: sbt
+
+      - name: Setup SBT
+        uses: sbt/setup-sbt@v1
+
+      - run: sbt 'scalafixAll --check'
diff --git a/.scalafix.conf b/.scalafix.conf
new file mode 100644
index 0000000..7b1e65a
--- /dev/null
+++ b/.scalafix.conf
@@ -0,0 +1,7 @@
+rules = [
+  RemoveUnused
+  ExplicitResultTypes
+  ProcedureSyntax
+  RedundantSyntax
+]
+ExplicitResultTypes.memberVisibility = [Public]
diff --git a/.scalafmt.conf b/.scalafmt.conf
new file mode 100644
index 0000000..72988b1
--- /dev/null
+++ b/.scalafmt.conf
@@ -0,0 +1,7 @@
+version = 3.8.6
+runner.dialect = scala36
+maxColumn = 100
+align.preset=none
+rewrite.trailingCommas.style = always
+newlines.selectChains.style = keep
+newlines.selectChains.classicKeepAfterFirstBreak = true
diff --git a/README.md b/README.md
index 08195d3..e91e46a 100644
--- a/README.md
+++ b/README.md
@@ -28,3 +28,8 @@ $ ./jelly-cli --help
 - The binary will be available at `./target/graalvm-native-image/jelly-cli`.
 
 Alternatively, you can use the utility with your JVM (no ahead-of-time compilation), by running `sbt run`. 
+
+## Developer notes
+
+Run `sbt fixAll` before committing. Your code should be formatted and free of warnings.
+The CI checks will not pass if this is not the case.
diff --git a/build.sbt b/build.sbt
index 21d0d67..09be481 100644
--- a/build.sbt
+++ b/build.sbt
@@ -1,5 +1,4 @@
-ThisBuild / version := "0.1.0-SNAPSHOT"
-
+ThisBuild / semanticdbEnabled := true
 ThisBuild / scalaVersion := "3.6.4"
 
 resolvers +=
@@ -8,6 +7,8 @@ resolvers +=
 lazy val jenaV = "5.3.0"
 lazy val jellyV = "2.8.0+14-4181e89a-SNAPSHOT"
 
+addCommandAlias("fixAll", "scalafixAll; scalafmtAll")
+
 def isDevBuild: Boolean =
   sys.env.get("DEV_BUILD").exists(s => s != "0" && s != "false")
 
@@ -25,6 +26,14 @@ lazy val root = (project in file("."))
       "com.github.alexarchambault" %% "case-app" % "2.1.0-M30",
       "org.scalatest" %% "scalatest" % "3.2.19" % Test,
     ),
+    scalacOptions ++= Seq(
+      "-Wunused:imports",
+      "-Werror",
+      "-feature",
+      "-deprecation",
+      "-unchecked",
+      "-explain",
+    ),
     buildInfoKeys := Seq[BuildInfoKey](
       version,
       scalaVersion,
diff --git a/project/plugins.sbt b/project/plugins.sbt
index 9abd225..4a1ca1c 100644
--- a/project/plugins.sbt
+++ b/project/plugins.sbt
@@ -1,3 +1,5 @@
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.13.1")
 addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.9.3")
 addSbtPlugin("com.github.sbt" % "sbt-native-packager" % "1.11.1")
+addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.14.0")
+addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.4")
diff --git a/src/main/scala/eu/neverblink/jelly/cli/App.scala b/src/main/scala/eu/neverblink/jelly/cli/App.scala
index 7973cf6..ef394a5 100644
--- a/src/main/scala/eu/neverblink/jelly/cli/App.scala
+++ b/src/main/scala/eu/neverblink/jelly/cli/App.scala
@@ -3,9 +3,8 @@ package eu.neverblink.jelly.cli
 import caseapp.*
 import eu.neverblink.jelly.cli.command.*
 
-/**
- * Main entrypoint.
- */
+/** Main entrypoint.
+  */
 object App extends CommandsEntryPoint:
   override def progName: String = "jelly-cli"
 
diff --git a/src/main/scala/eu/neverblink/jelly/cli/JellyCommand.scala b/src/main/scala/eu/neverblink/jelly/cli/JellyCommand.scala
index 118b818..9bb527e 100644
--- a/src/main/scala/eu/neverblink/jelly/cli/JellyCommand.scala
+++ b/src/main/scala/eu/neverblink/jelly/cli/JellyCommand.scala
@@ -9,17 +9,17 @@ import scala.compiletime.uninitialized
 object JellyCommand:
   val emptyRemainingArgs: RemainingArgs = RemainingArgs(Seq.empty, Seq.empty)
 
-abstract class JellyCommand[T : {Parser, Help}] extends Command[T]:
+abstract class JellyCommand[T: {Parser, Help}] extends Command[T]:
   private var isTest = false
   private var out = System.out
   private var err = System.err
   private var osOut: ByteArrayOutputStream = uninitialized
   private var osErr: ByteArrayOutputStream = uninitialized
 
-  /**
-   * Enable the "test mode" which captures stdout, stderr, exit code, and so on.
-   * @param test true to enable, false to disable
-   */
+  /** Enable the "test mode" which captures stdout, stderr, exit code, and so on.
+    * @param test
+    *   true to enable, false to disable
+    */
   def testMode(test: Boolean): Unit =
     this.isTest = test
     if test then
@@ -47,13 +47,16 @@ abstract class JellyCommand[T : {Parser, Help}] extends Command[T]:
       s
     else throw new IllegalStateException("Not in test mode")
 
-  /**
-   * Run the command in test mode, capturing stdout and stderr.
-   * @param options the command options
-   * @param remainingArgs the remaining arguments
-   * @throws ExitError if the command exits
-   * @return (stdout, stderr)
-   */
+  /** Run the command in test mode, capturing stdout and stderr.
+    * @param options
+    *   the command options
+    * @param remainingArgs
+    *   the remaining arguments
+    * @throws ExitError
+    *   if the command exits
+    * @return
+    *   (stdout, stderr)
+    */
   @throws[ExitError]
   def runTest(options: T, remainingArgs: RemainingArgs = emptyRemainingArgs): (String, String) =
     if !isTest then testMode(true)
diff --git a/src/main/scala/eu/neverblink/jelly/cli/command/FoolAround.scala b/src/main/scala/eu/neverblink/jelly/cli/command/FoolAround.scala
index 8425f8b..9f1b2f2 100644
--- a/src/main/scala/eu/neverblink/jelly/cli/command/FoolAround.scala
+++ b/src/main/scala/eu/neverblink/jelly/cli/command/FoolAround.scala
@@ -4,13 +4,12 @@ import caseapp.*
 import eu.neverblink.jelly.cli.JellyCommand
 
 case class FoolAroundOptions(
-  @HelpMessage("What to say")
-  say: String = "Hello, World!"
+    @HelpMessage("What to say")
+    say: String = "Hello, World!",
 )
 
-/**
- * "foo-bar" kind of command.
- */
+/** "foo-bar" kind of command.
+  */
 object FoolAround extends JellyCommand[FoolAroundOptions]:
   // https://alexarchambault.github.io/case-app/commands/
   override def names: List[List[String]] = List(
diff --git a/src/main/scala/eu/neverblink/jelly/cli/command/Version.scala b/src/main/scala/eu/neverblink/jelly/cli/command/Version.scala
index 5c265ae..29fe4f0 100644
--- a/src/main/scala/eu/neverblink/jelly/cli/command/Version.scala
+++ b/src/main/scala/eu/neverblink/jelly/cli/command/Version.scala
@@ -16,10 +16,10 @@ object Version extends JellyCommand[VersionOptions]:
       .find(_.startsWith("org.apache.jena:jena-core:")).get.split(":")(2)
     val jellyV = BuildInfo.libraryDependencies
       .find(_.startsWith("eu.ostrzyciel.jelly:jelly-jena:")).get.split(":")(2)
-    printLine(
-      f"""jelly-cli   ${BuildInfo.version}
+    printLine(f"""
+         |jelly-cli   ${BuildInfo.version}
          |----------------------------------------------
          |Jelly-JVM   $jellyV
          |Apache Jena $jenaV
          |JVM         ${System.getProperty("java.vm.name")} ${System.getProperty("java.vm.version")}
-         |""".stripMargin)
+         |""".stripMargin.trim)
diff --git a/src/test/scala/eu/neverblink/jelly/cli/command/VersionSpec.scala b/src/test/scala/eu/neverblink/jelly/cli/command/VersionSpec.scala
index fc4f9f9..3059933 100644
--- a/src/test/scala/eu/neverblink/jelly/cli/command/VersionSpec.scala
+++ b/src/test/scala/eu/neverblink/jelly/cli/command/VersionSpec.scala
@@ -7,8 +7,8 @@ class VersionSpec extends AnyWordSpec, Matchers:
   "version command" should {
     "print something" in {
       val (out, err) = Version.runTest(VersionOptions())
-      out should startWith ("jelly-cli")
-      out should include ("Jelly-JVM")
-      out should include ("Apache Jena")
+      out should startWith("jelly-cli")
+      out should include("Jelly-JVM")
+      out should include("Apache Jena")
     }
   }