diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 711e2f3..f9a0909 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -39,5 +39,5 @@ jobs:
           path: .devenv/state/.bundle
           key: ${{ runner.os }}-gems-${{ hashFiles('Gemfile.lock') }}
           restore-keys: ${{ runner.os }}-gems-
-      - name: Run the default task
-        run: devenv shell -- bin/rake
+      - name: Run the tests
+        run: devenv tasks run test:unit test:mutate
diff --git a/Rakefile b/Rakefile
index eead8d7..6a897fa 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,17 +1,4 @@
 # frozen_string_literal: true
 
 require "bundler/gem_tasks"
-require "minitest/test_task"
 require_relative "lib/en57/tasks"
-
-Minitest::TestTask.create
-
-task :mutate do
-  system("bin/mutant run")
-end
-
-task :mutate_since do
-  system("bin/mutant run --since #{ENV.fetch("MUTANT_SINCE")}")
-end
-
-task default: %i[test mutate_since]
diff --git a/devenv.nix b/devenv.nix
index 7644da6..9e725eb 100644
--- a/devenv.nix
+++ b/devenv.nix
@@ -20,9 +20,16 @@
     "app:setup".exec = "bundle install --quiet";
     "devenv:enterShell".after = [ "app:setup" ];
     "app:format".exec = "treefmt";
-    "app:test".exec = "bin/rake test";
-    "app:mutate".exec = "bin/mutant run";
-    "app:check".exec = "bin/rake"; # default: test + mutate_since
+
+    "test:unit" = {
+      exec = "bin/m test";
+      after = [ "app:setup" ];
+    };
+    "test:mutate" = {
+      exec = ''bin/mutant run --since "''${MUTANT_SINCE:-HEAD}"'';
+      after = [ "app:setup" ];
+    };
+    "test:pg".exec = "pg-regress";
   };
 
   treefmt.enable = true;
@@ -93,12 +100,11 @@
       --schedule=test/pg_regress/schedule_existing
   '';
 
-  git-hooks.hooks.rake = {
+  git-hooks.hooks.test = {
     enable = true;
-    name = "rake (test + mutate_since)";
-    entry = "${pkgs.writeShellScript "rake-precommit" ''
-      export MUTANT_SINCE="''${MUTANT_SINCE:-HEAD}"
-      exec bin/rake
+    name = "test:unit + test:mutate";
+    entry = "${pkgs.writeShellScript "pre-commit-test" ''
+      exec devenv tasks run test:unit test:mutate
     ''}";
     pass_filenames = false;
     language = "system";