diff --git a/pkg/wakaama/Kconfig b/pkg/wakaama/Kconfig
index 609f0f8e31..c6fd07d6ab 100644
--- a/pkg/wakaama/Kconfig
+++ b/pkg/wakaama/Kconfig
@@ -26,6 +26,14 @@ config LWM2M_DEVICE_TTL
     default 300
     help
         Lifetime of the device on the LwM2M server, expressed in seconds.
+        
+config LWM2M_COAP_DEFAULT_BLOCK_SIZE 
+     int "CoAP block size" 
+     range 4 10 
+     default 10
+     help 
+         Block transfer options support only power-of-two block sizes, from 2**4 (16) to 2**10 (1024) bytes.
+         This option represents the exponent of 2, which will be used for the block size.
 
 config LWM2M_LOCAL_PORT
     string "Port for the local LwM2M CoAP"
diff --git a/pkg/wakaama/Makefile.dep b/pkg/wakaama/Makefile.dep
index 4f9f449e22..ec713ee9e9 100644
--- a/pkg/wakaama/Makefile.dep
+++ b/pkg/wakaama/Makefile.dep
@@ -12,7 +12,6 @@ USEMODULE += wakaama_objects
 USEMODULE += wakaama_objects_device
 USEMODULE += wakaama_objects_security
 
-
 ifneq (,$(filter wakaama_objects_barometer,$(USEMODULE)))
     USEMODULE += wakaama_objects_ipso_sensor_base
 endif
@@ -39,6 +38,7 @@ endif
 
 USEMODULE += ztimer
 USEMODULE += ztimer_sec
+USEMODULE += random
 USEPKG += tlsf
 
 # If logs for the package are active, we need fmt
diff --git a/pkg/wakaama/Makefile.include b/pkg/wakaama/Makefile.include
index 8180eb4fc3..69ca42848e 100644
--- a/pkg/wakaama/Makefile.include
+++ b/pkg/wakaama/Makefile.include
@@ -9,9 +9,6 @@ INCLUDES += -I$(PKGDIRBASE)/wakaama/coap/er-coap-13
 # NOTE: Use wakaama in client mode
 CFLAGS += -DLWM2M_CLIENT_MODE
 
-# NOTE: "Default CoAP block size; Used if not set on a per-target basis"
-CFLAGS += -DLWM2M_COAP_DEFAULT_BLOCK_SIZE=1024
-
 # Translate 'CONFIG_' options to package specific flags. This checks if the
 # option is being set via Kconfig or CFLAGS
 ifneq (,$(or $(CONFIG_LWM2M_BOOTSTRAP),$(filter -DCONFIG_LWM2M_BOOTSTRAP=1,$(CFLAGS))))
@@ -22,5 +19,12 @@ ifneq (,$(or $(CONFIG_LWM2M_WITH_LOGS),$(filter -DCONFIG_LWM2M_WITH_LOGS=1,$(CFL
   CFLAGS += -DLWM2M_WITH_LOGS=1
 endif
 
+# NOTE: "Default CoAP block size; Used if not set on a per-target basis"
+ifeq (,$(CONFIG_LWM2M_COAP_DEFAULT_BLOCK_SIZE))
+  CFLAGS += -DLWM2M_COAP_DEFAULT_BLOCK_SIZE=1024
+else
+  CFLAGS += -DLWM2M_COAP_DEFAULT_BLOCK_SIZE='1<<$(CONFIG_LWM2M_COAP_DEFAULT_BLOCK_SIZE)'
+endif
+
 PSEUDOMODULES += wakaama
 PSEUDOMODULES += wakaama_client_dtls
diff --git a/pkg/wakaama/contrib/lwm2m_platform.c b/pkg/wakaama/contrib/lwm2m_platform.c
index 0097398be5..46b9cfc9a2 100644
--- a/pkg/wakaama/contrib/lwm2m_platform.c
+++ b/pkg/wakaama/contrib/lwm2m_platform.c
@@ -36,6 +36,7 @@
 
 #include "ztimer.h"
 #include "tlsf.h"
+#include "random.h"
 
 #include "lwm2m_platform.h"
 #include "lwm2m_client_config.h"
@@ -106,6 +107,10 @@ time_t lwm2m_gettime(void)
     return (time_t)(ztimer_now(ZTIMER_SEC));
 }
 
+int lwm2m_seed(void) {
+    return random_uint32();
+}
+
 /* For clang we need to specify that the first argument will be a format string
  * for print
  */