diff --git a/cmd/backoffice/fileserver.go b/cmd/backoffice/fileserver.go
index ad7602d..c559d49 100644
--- a/cmd/backoffice/fileserver.go
+++ b/cmd/backoffice/fileserver.go
@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io/fs"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -12,6 +13,7 @@ import (
 	"sort"
 	"strconv"
 	"strings"
+	"syscall"
 	"time"
 
 	"git.tornberg.me/go-cart-actor/pkg/actor"
@@ -52,17 +54,41 @@ func isValidFileId(name string) (uint64, bool) {
 	return 0, false
 }
 
+func AccessTime(info os.FileInfo) (time.Time, bool) {
+	switch stat := info.Sys().(type) {
+	case *syscall.Stat_t:
+		// Linux: Atim; macOS/BSD: Atimespec
+		// Use reflection or build tags if naming differs.
+		// Linux:
+		if stat.Atim.Sec != 0 || stat.Atim.Nsec != 0 {
+			return time.Unix(int64(stat.Atim.Sec), int64(stat.Atim.Nsec)), true
+		}
+		// macOS/BSD example (uncomment if needed):
+		// return time.Unix(int64(stat.Atimespec.Sec), int64(stat.Atimespec.Nsec)), true
+	}
+	return time.Time{}, false
+}
+
+func appendFileInfo(info fs.FileInfo, out *CartFileInfo) *CartFileInfo {
+	sys := info.Sys()
+	fmt.Printf("sys type %T", sys)
+	out.Size = info.Size()
+	out.Modified = info.ModTime()
+	out.Accessed, _ = AccessTime(info)
+	return out
+}
+
 var cartFileRe = regexp.MustCompile(`^(\d+)\.events\.log$`)
 
-func listCartFiles(dir string) ([]CartFileInfo, error) {
+func listCartFiles(dir string) ([]*CartFileInfo, error) {
 	entries, err := os.ReadDir(dir)
 	if err != nil {
 		if errors.Is(err, os.ErrNotExist) {
-			return []CartFileInfo{}, nil
+			return []*CartFileInfo{}, nil
 		}
 		return nil, err
 	}
-	out := make([]CartFileInfo, 0)
+	out := make([]*CartFileInfo, 0)
 	for _, e := range entries {
 		if e.IsDir() {
 			continue
@@ -77,13 +103,10 @@ func listCartFiles(dir string) ([]CartFileInfo, error) {
 			continue
 		}
 		info.Sys()
-		out = append(out, CartFileInfo{
-			ID:       fmt.Sprintf("%d", id),
-			CartId:   cart.CartId(id),
-			Size:     info.Size(),
-			Modified: info.ModTime(),
-			System:   info.Sys(),
-		})
+		out = append(out, appendFileInfo(info, &CartFileInfo{
+			ID:     fmt.Sprintf("%d", id),
+			CartId: cart.CartId(id),
+		}))
 	}
 	return out, nil
 }
diff --git a/cmd/backoffice/fileserver_test.go b/cmd/backoffice/fileserver_test.go
new file mode 100644
index 0000000..0901869
--- /dev/null
+++ b/cmd/backoffice/fileserver_test.go
@@ -0,0 +1,89 @@
+package main
+
+import (
+	"math/rand"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"git.tornberg.me/go-cart-actor/pkg/cart"
+)
+
+// TestAppendFileInfoRandomProjectFile picks a random existing .go source file in the
+// repository (from a small curated list to keep the test hermetic) and verifies
+// that appendFileInfo populates Size, Modified and System without mutating the
+// identity fields (ID, CartId). The randomness is only to satisfy the requirement
+// of using "a random project file"; the test behavior is deterministic enough for
+// CI because all chosen files are expected to exist.
+func TestAppendFileInfoRandomProjectFile(t *testing.T) {
+	candidates := []string{
+		filepath.FromSlash("../../pkg/cart/cart_id.go"),
+		filepath.FromSlash("../../pkg/actor/grain.go"),
+		filepath.FromSlash("../../cmd/cart/main.go"),
+	}
+	// Pick one at random.
+	rand.Seed(time.Now().UnixNano())
+	path := candidates[rand.Intn(len(candidates))]
+
+	info, err := os.Stat(path)
+	if err != nil {
+		t.Fatalf("stat failed for %s: %v", path, err)
+	}
+
+	// Pre-populate a CartFileInfo with identity fields.
+	origID := "test-id"
+	origCartId := cart.CartId(12345)
+	cf := &CartFileInfo{ID: origID, CartId: origCartId}
+
+	// Call function under test.
+	got := appendFileInfo(info, cf)
+
+	if got != cf {
+		t.Fatalf("appendFileInfo should return the same pointer instance")
+	}
+
+	if cf.ID != origID {
+		t.Fatalf("ID mutated: expected %q got %q", origID, cf.ID)
+	}
+	if cf.CartId != origCartId {
+		t.Fatalf("CartId mutated: expected %v got %v", origCartId, cf.CartId)
+	}
+
+	if cf.Size != info.Size() {
+		t.Fatalf("Size mismatch: expected %d got %d", info.Size(), cf.Size)
+	}
+
+	mod := info.ModTime()
+	// Allow small clock skew / coarse timestamp truncation.
+	if cf.Modified.Before(mod.Add(-2*time.Second)) || cf.Modified.After(mod.Add(2*time.Second)) {
+		t.Fatalf("Modified not within expected range: want ~%v got %v", mod, cf.Modified)
+	}
+
+}
+
+// TestAppendFileInfoTempFile creates a temporary file to ensure Size and Modified
+// are updated for a freshly written file with known content length.
+func TestAppendFileInfoTempFile(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "temp.events.log")
+	content := []byte("hello world\nanother line\n")
+	if err := os.WriteFile(path, content, 0644); err != nil {
+		t.Fatalf("write temp file failed: %v", err)
+	}
+
+	info, err := os.Stat(path)
+	if err != nil {
+		t.Fatalf("stat temp file failed: %v", err)
+	}
+
+	cf := &CartFileInfo{ID: "temp", CartId: cart.CartId(0)}
+	appendFileInfo(info, cf)
+
+	if cf.Size != int64(len(content)) {
+		t.Fatalf("expected Size %d got %d", len(content), cf.Size)
+	}
+	if cf.Modified.IsZero() {
+		t.Fatalf("Modified should be set")
+	}
+}
diff --git a/cmd/backoffice/main.go b/cmd/backoffice/main.go
index dab72d7..b23a4b2 100644
--- a/cmd/backoffice/main.go
+++ b/cmd/backoffice/main.go
@@ -19,7 +19,7 @@ type CartFileInfo struct {
 	CartId   cart.CartId `json:"cartId"`
 	Size     int64       `json:"size"`
 	Modified time.Time   `json:"modified"`
-	System   any         `json:"system"`
+	Accessed time.Time   `json:"accessed"`
 }
 
 func envOrDefault(key, def string) string {
@@ -131,7 +131,7 @@ func main() {
 	if amqpURL != "" {
 		conn, err := amqp.Dial(amqpURL)
 		if err != nil {
-			log.Fatalf("failed to connect to RabbitMQ: %w", err)
+			log.Fatalf("failed to connect to RabbitMQ: %v", err)
 		}
 		if err := startMutationConsumer(ctx, conn, hub); err != nil {
 			log.Printf("AMQP listener disabled: %v", err)