diff --git a/SUBSYSTEMS.md b/SUBSYSTEMS.md
index e965338857..27d202ca43 100644
--- a/SUBSYSTEMS.md
+++ b/SUBSYSTEMS.md
@@ -78,10 +78,14 @@ affect more than one module.
 
 # Kernel (core)
 
+  - Kaspar Schleiser (@kaspar030)
+
 # System libraries
 
 ## High-level timer API (xtimer, ztimer)
 
+  - Kaspar Schleiser (@kaspar030)
+
 ## Power Management
 
 ## MTD Subsystem
@@ -101,6 +105,7 @@ affect more than one module.
 ## RUST support
 
   - Christian Amsüss (@chrysn)
+  - Kaspar Schleiser (@kaspar030)
 
 ## C++ support
 
@@ -192,6 +197,10 @@ affect more than one module.
 
 # Build System
 
+  - Kaspar Schleiser (@kaspar030)
+
 # Documentation
 
 # Testing/CI
+
+  - Kaspar Schleiser (@kaspar030)