diff --git a/README.md b/README.md
index b3efa27..fe697be 100644
--- a/README.md
+++ b/README.md
@@ -5,25 +5,40 @@ ebpf - Pure-Perl interface for eBPF (extended Berkeley Packet Filter)
 
 # SYNOPSIS
 
-    use Sys::Ebpf::;
+    use utf8;
+    use Sys::Ebpf::Loader;
+    use Sys::Ebpf::Link::Perf::Kprobe;
 
-    # Create a new eBPF loader
-    my $loader = Sys::Ebpf::loader->new();
+    my $file   = "kprobe.o";
+    my $loader = Sys::Ebpf::Loader->new($file);
+    my $data   = $loader->load_elf();
 
-    # Load a BPF map
-    my $map_fd = $loader->load_bpf_map({
-        map_type => Sys::Ebpf::Constants::bpf_map_type::BPF_MAP_TYPE_ARRAY,
-        key_size => 4,
-        value_size => 8,
-        max_entries => 1,
-        map_flags => 0,
-        map_name => "my_map"
-    });
+    my $kprobe_fn = "kprobe/sys_execve";
+
+    my ( $map_data, $prog_fd ) = $loader->load_bpf($kprobe_fn);
+    my $map_kprobe_map = $map_data->{kprobe_map};
+    $map_kprobe_map->{key_schema}   = [ [ 'kprobe_map_key',   'uint32' ], ];
+    $map_kprobe_map->{value_schema} = [ [ 'kprobe_map_value', 'uint64' ], ];
 
     # Pin the map to a file
     $loader->pin_bpf_map($map_fd, "/sys/fs/bpf/my_map");
 
-    # TBA...
+    # attach kprobe
+    my $kprobe_info = Sys::Ebpf::Link::Perf::Kprobe::attach_kprobe( $prog_fd, $kprobe_fn );
+
+    # show map code from kprobe
+    while (1) {
+        my $key   = { kprobe_map_key => 0 };
+        my $value = $map_kprobe_map->lookup($key);
+        if ( defined $value ) {
+            print Dumper($value);
+            printf "%s called %d times\n", $kprobe_fn, $value->{kprobe_map_value};
+        }
+        else {
+            warn "Failed to read map value\n";
+        }
+        sleep(1);
+    }
 
 # DESCRIPTION