diff --git a/src/fsfw/serialize/SerializeIF.h b/src/fsfw/serialize/SerializeIF.h
index de5abaeb5..ad8d37309 100644
--- a/src/fsfw/serialize/SerializeIF.h
+++ b/src/fsfw/serialize/SerializeIF.h
@@ -66,7 +66,7 @@ class SerializeIF {
    * Gets the size of a object if it would be serialized in a buffer
    * @return Size of serialized object
    */
-  virtual size_t getSerializedSize() const = 0;
+  [[nodiscard]] virtual size_t getSerializedSize() const = 0;
 
   /**
    * @brief
@@ -99,7 +99,7 @@ class SerializeIF {
    * @param streamEndianness
    * @return
    */
-  virtual ReturnValue_t  serialize(uint8_t* buffer, size_t maxSize, Endianness streamEndianness) {
+  virtual ReturnValue_t  serialize(uint8_t* buffer, size_t maxSize, Endianness streamEndianness) const {
     size_t tmpSize = 0;
     return serialize(&buffer, &tmpSize, maxSize, streamEndianness);
   }
diff --git a/unittests/tmtcpacket/testCcsds.cpp b/unittests/tmtcpacket/testCcsds.cpp
index 28b255e5b..a2679896d 100644
--- a/unittests/tmtcpacket/testCcsds.cpp
+++ b/unittests/tmtcpacket/testCcsds.cpp
@@ -43,7 +43,7 @@ TEST_CASE("CCSDS Packet ID", "[ccsds-packet-id]") {
     packetId.secHeaderFlag = false;
     packetId.packetType = ccsds::PacketType::TM;
     REQUIRE(packetId.raw() == 0x1ff);
-    REQUIRE(packetId.serialize(&ptr, &serLen, buf.size(), SerializeIF::Endianness::NETWORK) ==
+    REQUIRE(packetId.serialize(buf.data(), buf.size(), SerializeIF::Endianness::NETWORK) ==
             HasReturnvaluesIF::RETURN_OK);
     REQUIRE(buf[0] == 0x1);
     REQUIRE(buf[1] == 0xff);