diff --git a/pkg/cayenne-lpp/doc.txt b/pkg/cayenne-lpp/doc.txt
index 4420b5d20d..05f3377df4 100644
--- a/pkg/cayenne-lpp/doc.txt
+++ b/pkg/cayenne-lpp/doc.txt
@@ -1,7 +1,7 @@
 /**
  * @defgroup pkg_cayenne-lpp Cayenne Low Power Payload (LPP)
  * @ingroup  pkg
- * @ingroup  sys
+ * @ingroup  sys_serialization
  * @brief    Provides a RIOT support for Cayenne LPP format
  *
  * The Cayenne Low Power Payload (LPP) provides a convenient and easy way to
diff --git a/pkg/cn-cbor/doc.txt b/pkg/cn-cbor/doc.txt
index ed68b593d4..07ac83099d 100644
--- a/pkg/cn-cbor/doc.txt
+++ b/pkg/cn-cbor/doc.txt
@@ -1,7 +1,7 @@
 /**
  * @defgroup pkg_cn-cbor cn-cbor
  * @ingroup  pkg
- * @ingroup  sys
+ * @ingroup  sys_serialization
  * @brief    A constrained node implementation of CBOR in C
  *
  * @see      https://github.com/cabo/cn-cbor
diff --git a/pkg/jsmn/doc.txt b/pkg/jsmn/doc.txt
index 76cbd8a10e..a251a6cdf6 100644
--- a/pkg/jsmn/doc.txt
+++ b/pkg/jsmn/doc.txt
@@ -1,8 +1,8 @@
 /**
  * @defgroup pkg_jsmn  JSON parser library
  * @ingroup  pkg
- * @ingroup  sys
+ * @ingroup  sys_serialization
  * @brief    Provides a JSON parser library to RIOT
  *
  * @see      https://github.com/zserge/jsmn
- */
\ No newline at end of file
+ */
diff --git a/pkg/minmea/doc.txt b/pkg/minmea/doc.txt
index db71764e21..61b12ce207 100644
--- a/pkg/minmea/doc.txt
+++ b/pkg/minmea/doc.txt
@@ -1,7 +1,7 @@
 /**
  * @defgroup pkg_minmea   GPS parser library 
  * @ingroup  pkg
- * @ingroup  sys
+ * @ingroup  sys_serialization
  * @brief    Provides a GPS parser library to RIOT
  *
  * # Introduction
@@ -15,4 +15,4 @@
  * Licensed under WTFPL.
  *
  * @see      https://github.com/cloudyourcar/minmea
- */
\ No newline at end of file
+ */
diff --git a/sys/doc.txt b/sys/doc.txt
index ee4a2fca9d..12497fb07b 100644
--- a/sys/doc.txt
+++ b/sys/doc.txt
@@ -34,3 +34,9 @@
  * @ingroup     sys
  * @brief       Provides memory management implementations and utilities
  */
+
+/**
+ * @defgroup    sys_serialization Serialization
+ * @ingroup     sys
+ * @brief       Utilities for data serialization
+ */
diff --git a/sys/include/base64.h b/sys/include/base64.h
index 46f332a321..c678ef368a 100644
--- a/sys/include/base64.h
+++ b/sys/include/base64.h
@@ -9,7 +9,7 @@
 
 /**
  * @defgroup    sys_base64 base64 encoder decoder
- * @ingroup     sys
+ * @ingroup     sys_serialization
  * @brief       base64 encoder and decoder
  * @{
  *
diff --git a/sys/include/ubjson.h b/sys/include/ubjson.h
index fad8544fa1..fd60cb9c3c 100644
--- a/sys/include/ubjson.h
+++ b/sys/include/ubjson.h
@@ -17,9 +17,9 @@
  */
 
 /**
- * @defgroup    sys_ubjson Universal Binary JSON
- * @ingroup     sys
- * @brief       A library to read and write UBJSON serialized data.
+ * @defgroup sys_ubjson  Universal Binary JSON library
+ * @ingroup  sys_serialization
+ * @brief    Provides a library to read and write UBJSON serialized data
  * @{
  *
  * @file
diff --git a/sys/ubjson/ubjson-read.c b/sys/ubjson/ubjson-read.c
index 42dfb85dbe..c53d56fb66 100644
--- a/sys/ubjson/ubjson-read.c
+++ b/sys/ubjson/ubjson-read.c
@@ -17,7 +17,7 @@
  */
 
 /**
- * @ingroup     sys
+ * @ingroup     sys_ubjson
  * @{
  * @file
  * @brief       Universal Binary JSON deserializer
diff --git a/sys/ubjson/ubjson-write.c b/sys/ubjson/ubjson-write.c
index 9a05539fa5..4c8af605c9 100644
--- a/sys/ubjson/ubjson-write.c
+++ b/sys/ubjson/ubjson-write.c
@@ -17,7 +17,7 @@
  */
 
 /**
- * @ingroup     sys
+ * @ingroup     sys_ubjson
  * @{
  * @file
  * @brief       Universal Binary JSON deserializer