diff --git a/pkg/prebuild/prepare/core_test.go b/pkg/prebuild/prepare/core_test.go
index 3d856cb3..75e5c348 100644
--- a/pkg/prebuild/prepare/core_test.go
+++ b/pkg/prebuild/prepare/core_test.go
@@ -5,10 +5,104 @@
 package prepare
 
 import (
+	"os"
+	"os/exec"
 	"slices"
 	"testing"
+
+	"github.com/arduino/go-paths-helper"
+	"github.com/roddhjav/apparmor.d/pkg/prebuild/cfg"
 )
 
+func chdirGitRoot() {
+	cmd := exec.Command("git", "rev-parse", "--show-toplevel")
+	out, err := cmd.Output()
+	if err != nil {
+		panic(err)
+	}
+	root := string(out)[0 : len(out)-1]
+	if err := os.Chdir(root); err != nil {
+		panic(err)
+	}
+}
+
+func TestTask_Apply(t *testing.T) {
+	tests := []struct {
+		name        string
+		task        Task
+		want        string
+		wantErr     bool
+		wantFiles   paths.PathList
+		wantNoFiles paths.PathList
+	}{
+		{
+			name:      "synchronise",
+			task:      Tasks["synchronise"],
+			wantErr:   false,
+			wantFiles: paths.PathList{cfg.RootApparmord.Join("/groups/_full/systemd")},
+		},
+		{
+			name:    "ignore",
+			task:    Tasks["ignore"],
+			wantErr: false,
+			want:    "dists/ignore/main.ignore",
+		},
+		{
+			name:      "merge",
+			task:      Tasks["merge"],
+			wantErr:   false,
+			wantFiles: paths.PathList{cfg.RootApparmord.Join("aa-log")},
+		},
+		{
+			name:    "configure",
+			task:    Tasks["configure"],
+			wantErr: false,
+		},
+		{
+			name:    "setflags",
+			task:    Tasks["setflags"],
+			wantErr: false,
+			want:    "dists/flags/main.flags",
+		},
+		{
+			name:      "systemd-default",
+			task:      Tasks["systemd-default"],
+			wantErr:   false,
+			wantFiles: paths.PathList{cfg.Root.Join("systemd/system/dbus.service")},
+		},
+		{
+			name:      "systemd-early",
+			task:      Tasks["systemd-early"],
+			wantErr:   false,
+			wantFiles: paths.PathList{cfg.Root.Join("systemd/system/pcscd.service")},
+		},
+		{
+			name:      "fsp",
+			task:      Tasks["fsp"],
+			wantErr:   false,
+			wantFiles: paths.PathList{cfg.RootApparmord.Join("systemd")},
+		},
+	}
+	chdirGitRoot()
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := tt.task.Apply()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Task.Apply() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if tt.want != "" && !slices.Contains(got, tt.want) {
+				t.Errorf("Task.Apply() = %v, want %v", got, tt.want)
+			}
+			for _, file := range tt.wantFiles {
+				if file.NotExist() {
+					t.Errorf("Task.Apply() = %v, want %v", file, "exist")
+				}
+			}
+		})
+	}
+}
+
 func TestRegister(t *testing.T) {
 	tests := []struct {
 		name        string
@@ -22,7 +116,6 @@ func TestRegister(t *testing.T) {
 		},
 	}
 	for _, tt := range tests {
-
 		t.Run(tt.name, func(t *testing.T) {
 			Register(tt.names...)
 			for _, name := range tt.names {