diff --git a/README.md b/README.md
index d19c874..e0599a6 100644
--- a/README.md
+++ b/README.md
@@ -210,6 +210,7 @@ Only main chapters:
:small_orange_diamond: strace - diagnostic, debugging and instructional userspace utility for Linux.
:small_orange_diamond: DTrace - is a performance analysis and troubleshooting tool.
:small_orange_diamond: ltrace - is a library call tracer, used to trace calls made by programs to library functions.
+ :small_orange_diamond: perf-tools - performance analysis tools based on Linux perf_events (aka perf) and ftrace.
:small_orange_diamond: sysdig - system exploration and troubleshooting tool with first class support for containers.
:small_orange_diamond: Valgrind - is an instrumentation framework for building dynamic analysis tools.
:small_orange_diamond: glances - cross-platform system monitoring tool written in Python.