diff --git a/CHANGELOG.md b/CHANGELOG.md
index e197ee83..b0b98e4d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## Changes
 
+- Bump C++ required version to C++17. Every project which uses the FSFW and every modern
+  compiler supports it
+  PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/622
 - HAL Linux SPI: Set the Clock Default State when setting new SPI speed
   and mode
   PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/573
@@ -52,9 +55,18 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
   PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/594
 - Added ETL dependency and improved library dependency management
   PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/592
+- `Subsystem`: New API to add table and sequence entries
 
 ## Fixed
 
+- TCP TMTC Server: `MutexGuard` was not created properly in
+  `TcpTmTcServer::handleTmSending(socket_t connSocket, bool& tmSent)` call.
+  PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/618
+- Fix infinite recursion in `prepareHealthSetReply` of PUS Health Service 201.
+  Is not currently used right now but might be used in the future
+  PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/617
+- Move some CMake directives further up top so they are not ignored
+  PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/621
 - Small bugfix in STM32 HAL for SPI
   PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/599
 - HAL GPIO: Improved error checking in `LinuxLibgpioIF::configureGpios(...)`. If a GPIO
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d8ca812e..1df1008b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,15 @@
 cmake_minimum_required(VERSION 3.13)
 
+set(LIB_FSFW_NAME fsfw)
+project(${LIB_FSFW_NAME})
+
+if(NOT CMAKE_CXX_STANDARD)
+    set(CMAKE_CXX_STANDARD 17)
+    set(CMAKE_CXX_STANDARD_REQUIRED True)
+elseif(${CMAKE_CXX_STANDARD} LESS 17)
+    message(FATAL_ERROR "Compiling the FSFW requires a minimum of C++17 support")
+endif()
+
 set(FSFW_VERSION 4)
 set(FSFW_SUBVERSION 0)
 set(FSFW_REVISION 0)
@@ -10,14 +20,15 @@ set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake" ${CMAKE_MODULE_PATH})
 set(FSFW_ETL_LIB_MAJOR_VERSION 20 CACHE STRING
     "ETL library major version requirement"
 )
-set(FSFW_ETL_LIB_VERSION ${FSFW_ETL_LIB_MAJOR_VERSION}.27.2 CACHE STRING
+set(FSFW_ETL_LIB_VERSION ${FSFW_ETL_LIB_MAJOR_VERSION}.27.3 CACHE STRING
     "ETL library exact version requirement"
 )
+set(FSFW_ETL_LINK_TARGET etl::etl)
 
 set(FSFW_CATCH2_LIB_MAJOR_VERSION 3 CACHE STRING
     "Catch2 library major version requirement"
 )
-set(FSFW_CATCH2_LIB_VERSION v${FSFW_CATCH2_LIB_MAJOR_VERSION}.0.0-preview4 CACHE STRING
+set(FSFW_CATCH2_LIB_VERSION v${FSFW_CATCH2_LIB_MAJOR_VERSION}.0.0-preview5 CACHE STRING
     "Catch2 library exact version requirement"
 )
 
@@ -54,11 +65,10 @@ option(FSFW_ADD_TMSTORAGE "Compile with tm storage components" OFF)
 # Contrib sources
 option(FSFW_ADD_SGP4_PROPAGATOR "Add SGP4 propagator code" OFF)
 
-set(LIB_FSFW_NAME fsfw)
+
 set(FSFW_TEST_TGT fsfw-tests)
 set(FSFW_DUMMY_TGT fsfw-dummy)
 
-project(${LIB_FSFW_NAME})
 add_library(${LIB_FSFW_NAME})
 
 if(FSFW_BUILD_UNITTESTS)
@@ -76,9 +86,7 @@ if(FSFW_BUILD_UNITTESTS)
             GIT_TAG        ${FSFW_CATCH2_LIB_VERSION}
         )
 
-        FetchContent_MakeAvailable(Catch2)
-        #fixes regression -preview4, to be confirmed in later releases
-        set_target_properties(Catch2 PROPERTIES DEBUG_POSTFIX "")
+        list(APPEND FSFW_FETCH_CONTENT_TARGETS Catch2)
     endif()
 
     set(FSFW_CONFIG_PATH tests/src/fsfw_tests/unit/testcfg)
@@ -123,7 +131,22 @@ if(NOT ${FSFW_ETL_LIB_NAME}_FOUND)
         GIT_TAG        ${FSFW_ETL_LIB_VERSION}
     )
 
-    FetchContent_MakeAvailable(etl)
+    list(APPEND FSFW_FETCH_CONTENT_TARGETS ${FSFW_ETL_LIB_NAME})
+endif()
+
+# The documentation for FetchContent recommends declaring all the dependencies
+# before making them available. We make all declared dependency available here
+# after their declaration
+if(FSFW_FETCH_CONTENT_TARGETS)
+    FetchContent_MakeAvailable(${FSFW_FETCH_CONTENT_TARGETS})
+    if(TARGET ${FSFW_ETL_LIB_NAME})
+        add_library(${FSFW_ETL_LINK_TARGET} ALIAS ${FSFW_ETL_LIB_NAME})
+    endif()
+    if(TARGET Catch2)
+        # Fixes regression -preview4, to be confirmed in later releases
+        # Related GitHub issue: https://github.com/catchorg/Catch2/issues/2417
+        set_target_properties(Catch2 PROPERTIES DEBUG_POSTFIX "")
+    endif()
 endif()
 
 set(FSFW_CORE_INC_PATH "inc")
@@ -138,12 +161,6 @@ target_include_directories(${LIB_FSFW_NAME} INTERFACE
     ${CMAKE_CURRENT_BINARY_DIR}
 )
 
-if(NOT CMAKE_CXX_STANDARD)
-    set(CMAKE_CXX_STANDARD 11)
-    set(CMAKE_CXX_STANDARD_REQUIRED True)
-elseif(${CMAKE_CXX_STANDARD} LESS 11)
-    message(FATAL_ERROR "Compiling the FSFW requires a minimum of C++11 support")
-endif()
 
 # Backwards comptability
 if(OS_FSFW AND NOT FSFW_OSAL)
@@ -387,7 +404,7 @@ target_compile_options(${LIB_FSFW_NAME} PRIVATE
 )
 
 target_link_libraries(${LIB_FSFW_NAME} PRIVATE
-    ${FSFW_ETL_LIB_NAME}
+    ${FSFW_ETL_LINK_TARGET}
     ${FSFW_ADDITIONAL_LINK_LIBS}
 )
 
diff --git a/automation/Dockerfile b/automation/Dockerfile
index 9df67fc8..0eb98fbb 100644
--- a/automation/Dockerfile
+++ b/automation/Dockerfile
@@ -6,3 +6,9 @@ RUN apt-get --yes upgrade
 #tzdata is a dependency, won't install otherwise
 ARG DEBIAN_FRONTEND=noninteractive
 RUN apt-get --yes install gcc g++ cmake make lcov git valgrind nano iputils-ping
+
+RUN git clone https://github.com/catchorg/Catch2.git && \
+	cd Catch2 && \
+	git checkout v3.0.0-preview5 && \
+	cmake -Bbuild -H. -DBUILD_TESTING=OFF && \
+	cmake --build build/ --target install
diff --git a/automation/Jenkinsfile b/automation/Jenkinsfile
index d1459e52..6abf5636 100644
--- a/automation/Jenkinsfile
+++ b/automation/Jenkinsfile
@@ -3,7 +3,7 @@ pipeline {
         BUILDDIR = 'build-tests'
     }
     agent {
-        docker { image 'fsfw-ci:d1'}
+        docker { image 'fsfw-ci:d2'}
     }
     stages {
         stage('Clean') {
diff --git a/hal/src/fsfw_hal/linux/CMakeLists.txt b/hal/src/fsfw_hal/linux/CMakeLists.txt
index 56d4bf48..f6d1a460 100644
--- a/hal/src/fsfw_hal/linux/CMakeLists.txt
+++ b/hal/src/fsfw_hal/linux/CMakeLists.txt
@@ -12,9 +12,14 @@ if(FSFW_HAL_LINUX_ADD_PERIPHERAL_DRIVERS)
 if(FSFW_HAL_LINUX_ADD_LIBGPIOD)
 	add_subdirectory(gpio)
 endif()
-	add_subdirectory(spi)
-	add_subdirectory(i2c)
 	add_subdirectory(uart)
+	# Adding those does not really make sense on Apple systems which
+	# are generally host systems. It won't even compile as the headers
+	# are missing
+	if(NOT APPLE)
+		add_subdirectory(i2c)
+		add_subdirectory(spi)
+	endif()
 endif()
 
 add_subdirectory(uio)
diff --git a/hal/src/fsfw_hal/linux/spi/SpiCookie.cpp b/hal/src/fsfw_hal/linux/spi/SpiCookie.cpp
index e6271c5e..c94fcdf1 100644
--- a/hal/src/fsfw_hal/linux/spi/SpiCookie.cpp
+++ b/hal/src/fsfw_hal/linux/spi/SpiCookie.cpp
@@ -1,4 +1,4 @@
-#include "fsfw_hal/linux/spi/SpiCookie.h"
+#include "SpiCookie.h"
 
 SpiCookie::SpiCookie(address_t spiAddress, gpioId_t chipSelect, std::string spiDev,
                      const size_t maxSize, spi::SpiModes spiMode, uint32_t spiSpeed)
diff --git a/hal/src/fsfw_hal/linux/uart/UartComIF.cpp b/hal/src/fsfw_hal/linux/uart/UartComIF.cpp
index 5aa72138..72c79df6 100644
--- a/hal/src/fsfw_hal/linux/uart/UartComIF.cpp
+++ b/hal/src/fsfw_hal/linux/uart/UartComIF.cpp
@@ -265,6 +265,7 @@ void UartComIF::configureBaudrate(struct termios* options, UartCookie* uartCooki
       cfsetispeed(options, B230400);
       cfsetospeed(options, B230400);
       break;
+#ifndef __APPLE__
     case UartBaudRate::RATE_460800:
       cfsetispeed(options, B460800);
       cfsetospeed(options, B460800);
@@ -313,6 +314,7 @@ void UartComIF::configureBaudrate(struct termios* options, UartCookie* uartCooki
       cfsetispeed(options, B4000000);
       cfsetospeed(options, B4000000);
       break;
+#endif // ! __APPLE__
     default:
 #if FSFW_CPP_OSTREAM_ENABLED == 1
       sif::warning << "UartComIF::configureBaudrate: Baudrate not supported" << std::endl;
diff --git a/src/fsfw/cfdp/pdu/HeaderSerializer.h b/src/fsfw/cfdp/pdu/HeaderSerializer.h
index 8f2fc3fd..1de97d63 100644
--- a/src/fsfw/cfdp/pdu/HeaderSerializer.h
+++ b/src/fsfw/cfdp/pdu/HeaderSerializer.h
@@ -44,7 +44,7 @@ class HeaderSerializer : public SerializeIF, public PduHeaderIF {
   cfdp::WidthInBytes getLenEntityIds() const override;
   cfdp::WidthInBytes getLenSeqNum() const override;
   cfdp::SegmentMetadataFlag getSegmentMetadataFlag() const override;
-  bool hasSegmentMetadataFlag() const;
+  bool hasSegmentMetadataFlag() const override;
   void setSegmentationControl(cfdp::SegmentationControl);
 
   void getSourceId(cfdp::EntityId& sourceId) const override;
diff --git a/src/fsfw/container/FixedArrayList.h b/src/fsfw/container/FixedArrayList.h
index c09a421e..11882537 100644
--- a/src/fsfw/container/FixedArrayList.h
+++ b/src/fsfw/container/FixedArrayList.h
@@ -2,6 +2,7 @@
 #define FIXEDARRAYLIST_H_
 
 #include <cmath>
+#include <limits>
 
 #include "ArrayList.h"
 /**
@@ -9,10 +10,8 @@
  */
 template <typename T, size_t MAX_SIZE, typename count_t = uint8_t>
 class FixedArrayList : public ArrayList<T, count_t> {
-#if !defined(_MSC_VER)
-  static_assert(MAX_SIZE <= (std::pow(2, sizeof(count_t) * 8) - 1),
+  static_assert(MAX_SIZE <= std::numeric_limits<count_t>::max(),
                 "count_t is not large enough to hold MAX_SIZE");
-#endif
  private:
   T data[MAX_SIZE];
 
diff --git a/src/fsfw/container/HybridIterator.h b/src/fsfw/container/HybridIterator.h
index e8b24a3d..ad000ec2 100644
--- a/src/fsfw/container/HybridIterator.h
+++ b/src/fsfw/container/HybridIterator.h
@@ -10,16 +10,23 @@ class HybridIterator : public LinkedElement<T>::Iterator, public ArrayList<T, co
   HybridIterator() {}
 
   HybridIterator(typename LinkedElement<T>::Iterator *iter)
-      : LinkedElement<T>::Iterator(*iter), value(iter->value), linked(true) {}
+      : LinkedElement<T>::Iterator(*iter), linked(true) {
+    if (iter != nullptr) {
+      value = iter->value;
+    }
+  }
 
-  HybridIterator(LinkedElement<T> *start)
-      : LinkedElement<T>::Iterator(start), value(start->value), linked(true) {}
+  HybridIterator(LinkedElement<T> *start) : LinkedElement<T>::Iterator(start), linked(true) {
+    if (start != nullptr) {
+      value = start->value;
+    }
+  }
 
   HybridIterator(typename ArrayList<T, count_t>::Iterator start,
                  typename ArrayList<T, count_t>::Iterator end)
       : ArrayList<T, count_t>::Iterator(start), value(start.value), linked(false), end(end.value) {
     if (value == this->end) {
-      value = NULL;
+      value = nullptr;
     }
   }
 
diff --git a/src/fsfw/controller/ControllerBase.h b/src/fsfw/controller/ControllerBase.h
index 7032f817..227b859b 100644
--- a/src/fsfw/controller/ControllerBase.h
+++ b/src/fsfw/controller/ControllerBase.h
@@ -55,7 +55,7 @@ class ControllerBase : public HasModesIF,
   virtual void performControlOperation() = 0;
 
   virtual ReturnValue_t checkModeCommand(Mode_t mode, Submode_t submode,
-                                         uint32_t *msToReachTheMode) = 0;
+                                         uint32_t *msToReachTheMode) override = 0;
 
   const object_id_t parentId;
 
@@ -80,9 +80,9 @@ class ControllerBase : public HasModesIF,
 
   /** Mode helpers */
   virtual void modeChanged(Mode_t mode, Submode_t submode);
-  virtual void startTransition(Mode_t mode, Submode_t submode);
-  virtual void getMode(Mode_t *mode, Submode_t *submode);
-  virtual void setToExternalControl();
+  virtual void startTransition(Mode_t mode, Submode_t submode) override;
+  virtual void getMode(Mode_t *mode, Submode_t *submode) override;
+  virtual void setToExternalControl() override;
   virtual void announceMode(bool recursive);
   /** HK helpers */
   virtual void changeHK(Mode_t mode, Submode_t submode, bool enable);
diff --git a/src/fsfw/datapool/PoolDataSetBase.h b/src/fsfw/datapool/PoolDataSetBase.h
index 1b4bacda..dc6ec135 100644
--- a/src/fsfw/datapool/PoolDataSetBase.h
+++ b/src/fsfw/datapool/PoolDataSetBase.h
@@ -109,7 +109,7 @@ class PoolDataSetBase : public PoolDataSetIF, public SerializeIF, public HasRetu
    */
   virtual ReturnValue_t unlockDataPool() override;
 
-  virtual uint16_t getFillCount() const;
+  virtual uint16_t getFillCount() const override;
 
   /* SerializeIF implementations */
   virtual ReturnValue_t serialize(uint8_t** buffer, size_t* size, const size_t maxSize,
diff --git a/src/fsfw/datapoollocal/LocalPoolDataSetBase.cpp b/src/fsfw/datapoollocal/LocalPoolDataSetBase.cpp
index 4a076212..62fdb184 100644
--- a/src/fsfw/datapoollocal/LocalPoolDataSetBase.cpp
+++ b/src/fsfw/datapoollocal/LocalPoolDataSetBase.cpp
@@ -94,13 +94,14 @@ ReturnValue_t LocalPoolDataSetBase::serializeWithValidityBuffer(
   ReturnValue_t result = HasReturnvaluesIF::RETURN_OK;
   const uint8_t validityMaskSize = std::ceil(static_cast<float>(fillCount) / 8.0);
   uint8_t *validityPtr = nullptr;
-#ifdef _MSC_VER
-  /* Use a std::vector here because MSVC will (rightly) not create a fixed size array
-  with a non constant size specifier */
-  std::vector<uint8_t> validityMask(validityMaskSize);
+#if defined(_MSC_VER) || defined(__clang__)
+  // Use a std::vector here because MSVC will (rightly) not create a fixed size array
+  // with a non constant size specifier. The Apple compiler (LLVM) will not accept
+  // the  initialization of a variable sized array
+  std::vector<uint8_t> validityMask(validityMaskSize, 0);
   validityPtr = validityMask.data();
 #else
-  uint8_t validityMask[validityMaskSize] = {0};
+  uint8_t validityMask[validityMaskSize] = {};
   validityPtr = validityMask;
 #endif
   uint8_t validBufferIndex = 0;
diff --git a/src/fsfw/datapoollocal/LocalPoolObjectBase.h b/src/fsfw/datapoollocal/LocalPoolObjectBase.h
index 56e190df..b2ffa4c1 100644
--- a/src/fsfw/datapoollocal/LocalPoolObjectBase.h
+++ b/src/fsfw/datapoollocal/LocalPoolObjectBase.h
@@ -23,8 +23,8 @@ class LocalPoolObjectBase : public PoolVariableIF, public HasReturnvaluesIF, pub
   LocalPoolObjectBase(object_id_t poolOwner, lp_id_t poolId, DataSetIF* dataSet = nullptr,
                       pool_rwm_t setReadWriteMode = pool_rwm_t::VAR_READ_WRITE);
 
-  void setReadWriteMode(pool_rwm_t newReadWriteMode);
-  pool_rwm_t getReadWriteMode() const;
+  void setReadWriteMode(pool_rwm_t newReadWriteMode) override;
+  pool_rwm_t getReadWriteMode() const override;
 
   bool isValid() const override;
   void setValid(bool valid) override;
diff --git a/src/fsfw/devicehandlers/DeviceHandlerBase.h b/src/fsfw/devicehandlers/DeviceHandlerBase.h
index 5e974831..5808b8e6 100644
--- a/src/fsfw/devicehandlers/DeviceHandlerBase.h
+++ b/src/fsfw/devicehandlers/DeviceHandlerBase.h
@@ -163,7 +163,7 @@ class DeviceHandlerBase : public DeviceHandlerIF,
    * @param counter Specifies which Action to perform
    * @return RETURN_OK for successful execution
    */
-  virtual ReturnValue_t performOperation(uint8_t counter);
+  virtual ReturnValue_t performOperation(uint8_t counter) override;
 
   /**
    * @brief  Initializes the device handler
@@ -173,7 +173,7 @@ class DeviceHandlerBase : public DeviceHandlerIF,
    * Calls fillCommandAndReplyMap().
    * @return
    */
-  virtual ReturnValue_t initialize();
+  virtual ReturnValue_t initialize() override;
 
   /**
    * @brief   Intialization steps performed after all tasks have been created.
@@ -1058,11 +1058,11 @@ class DeviceHandlerBase : public DeviceHandlerIF,
    * @param parameter1	Optional parameter 1
    * @param parameter2	Optional parameter 2
    */
-  void triggerEvent(Event event, uint32_t parameter1 = 0, uint32_t parameter2 = 0);
+  void triggerEvent(Event event, uint32_t parameter1 = 0, uint32_t parameter2 = 0) override;
   /**
    * Same as triggerEvent, but for forwarding if object is used as proxy.
    */
-  virtual void forwardEvent(Event event, uint32_t parameter1 = 0, uint32_t parameter2 = 0) const;
+  virtual void forwardEvent(Event event, uint32_t parameter1 = 0, uint32_t parameter2 = 0) const override;
 
   /**
    * Checks if current mode is transitional mode.
diff --git a/src/fsfw/globalfunctions/matching/MatchTree.h b/src/fsfw/globalfunctions/matching/MatchTree.h
index f7775d45..ec98e22a 100644
--- a/src/fsfw/globalfunctions/matching/MatchTree.h
+++ b/src/fsfw/globalfunctions/matching/MatchTree.h
@@ -25,7 +25,7 @@ class MatchTree : public SerializeableMatcherIF<T>, public BinaryTree<Serializea
       : BinaryTree<SerializeableMatcherIF<T>>(root.element), maxDepth(maxDepth) {}
   MatchTree() : BinaryTree<SerializeableMatcherIF<T>>(), maxDepth(-1) {}
   virtual ~MatchTree() {}
-  virtual bool match(T number) { return matchesTree(number); }
+  virtual bool match(T number) override { return matchesTree(number); }
   bool matchesTree(T number) {
     iterator iter = this->begin();
     if (iter == this->end()) {
@@ -179,6 +179,9 @@ class MatchTree : public SerializeableMatcherIF<T>, public BinaryTree<Serializea
   virtual ReturnValue_t cleanUpElement(iterator position) { return HasReturnvaluesIF::RETURN_OK; }
 
   bool matchSubtree(iterator iter, T number) {
+    if (iter == nullptr) {
+      return false;
+    }
     bool isMatch = iter->match(number);
     if (isMatch) {
       if (iter.left() == this->end()) {
diff --git a/src/fsfw/globalfunctions/matching/RangeMatcher.h b/src/fsfw/globalfunctions/matching/RangeMatcher.h
index 4e1f3922..c5962ab3 100644
--- a/src/fsfw/globalfunctions/matching/RangeMatcher.h
+++ b/src/fsfw/globalfunctions/matching/RangeMatcher.h
@@ -15,7 +15,7 @@ class RangeMatcher : public SerializeableMatcherIF<T> {
   RangeMatcher(T lowerBound, T upperBound, bool inverted = false)
       : inverted(inverted), lowerBound(lowerBound), upperBound(upperBound) {}
 
-  bool match(T input) {
+  bool match(T input) override {
     if (inverted) {
       return !doMatch(input);
     } else {
diff --git a/src/fsfw/monitoring/MonitoringMessageContent.h b/src/fsfw/monitoring/MonitoringMessageContent.h
index 0ac455eb..fb3ace3d 100644
--- a/src/fsfw/monitoring/MonitoringMessageContent.h
+++ b/src/fsfw/monitoring/MonitoringMessageContent.h
@@ -34,7 +34,7 @@ class MonitoringReportContent : public SerialLinkedListAdapter<SerializeIF> {
   SerializeElement<T> limitValue;
   SerializeElement<ReturnValue_t> oldState;
   SerializeElement<ReturnValue_t> newState;
-  uint8_t rawTimestamp[TimeStamperIF::MISSION_TIMESTAMP_SIZE];
+  uint8_t rawTimestamp[TimeStamperIF::MISSION_TIMESTAMP_SIZE] = {};
   SerializeElement<SerialBufferAdapter<uint8_t>> timestampSerializer;
   TimeStamperIF* timeStamper;
   MonitoringReportContent()
@@ -46,7 +46,6 @@ class MonitoringReportContent : public SerialLinkedListAdapter<SerializeIF> {
         limitValue(0),
         oldState(0),
         newState(0),
-        rawTimestamp({0}),
         timestampSerializer(rawTimestamp, sizeof(rawTimestamp)),
         timeStamper(NULL) {
     setAllNext();
diff --git a/src/fsfw/objectmanager/SystemObject.h b/src/fsfw/objectmanager/SystemObject.h
index 6d5b8303..eeb68b8f 100644
--- a/src/fsfw/objectmanager/SystemObject.h
+++ b/src/fsfw/objectmanager/SystemObject.h
@@ -48,9 +48,9 @@ class SystemObject : public SystemObjectIF {
   virtual ~SystemObject();
   object_id_t getObjectId() const override;
   virtual ReturnValue_t initialize() override;
-  virtual ReturnValue_t checkObjectConnections();
+  virtual ReturnValue_t checkObjectConnections() override;
 
-  virtual void forwardEvent(Event event, uint32_t parameter1 = 0, uint32_t parameter2 = 0) const;
+  virtual void forwardEvent(Event event, uint32_t parameter1 = 0, uint32_t parameter2 = 0) const override;
 };
 
 #endif /* FSFW_OBJECTMANAGER_SYSTEMOBJECT_H_ */
diff --git a/src/fsfw/osal/common/TcpTmTcServer.cpp b/src/fsfw/osal/common/TcpTmTcServer.cpp
index 2e6910c5..91cb9574 100644
--- a/src/fsfw/osal/common/TcpTmTcServer.cpp
+++ b/src/fsfw/osal/common/TcpTmTcServer.cpp
@@ -19,6 +19,8 @@
 #include <ws2tcpip.h>
 #elif defined(PLATFORM_UNIX)
 #include <netdb.h>
+
+#include <utility>
 #endif
 
 const std::string TcpTmTcServer::DEFAULT_SERVER_PORT = tcpip::DEFAULT_SERVER_PORT;
@@ -29,7 +31,7 @@ TcpTmTcServer::TcpTmTcServer(object_id_t objectId, object_id_t tmtcTcpBridge,
     : SystemObject(objectId),
       tmtcBridgeId(tmtcTcpBridge),
       receptionMode(receptionMode),
-      tcpConfig(customTcpServerPort),
+      tcpConfig(std::move(customTcpServerPort)),
       receptionBuffer(receptionBufferSize),
       ringBuffer(ringBufferSize, true) {}
 
@@ -103,7 +105,7 @@ ReturnValue_t TcpTmTcServer::initialize() {
 
 TcpTmTcServer::~TcpTmTcServer() { closeSocket(listenerTcpSocket); }
 
-ReturnValue_t TcpTmTcServer::performOperation(uint8_t opCode) {
+[[noreturn]] ReturnValue_t TcpTmTcServer::performOperation(uint8_t opCode) {
   using namespace tcpip;
   // If a connection is accepted, the corresponding socket will be assigned to the new socket
   socket_t connSocket = 0;
@@ -138,7 +140,6 @@ ReturnValue_t TcpTmTcServer::performOperation(uint8_t opCode) {
     closeSocket(connSocket);
     connSocket = 0;
   }
-  return HasReturnvaluesIF::RETURN_OK;
 }
 
 ReturnValue_t TcpTmTcServer::initializeAfterTaskCreation() {
@@ -159,7 +160,7 @@ void TcpTmTcServer::handleServerOperation(socket_t& connSocket) {
 #endif
 
   while (true) {
-    int retval = recv(connSocket, reinterpret_cast<char*>(receptionBuffer.data()),
+    ssize_t retval = recv(connSocket, reinterpret_cast<char*>(receptionBuffer.data()),
                       receptionBuffer.capacity(), tcpConfig.tcpFlags);
     if (retval == 0) {
       size_t availableReadData = ringBuffer.getAvailableReadData();
@@ -252,17 +253,17 @@ ReturnValue_t TcpTmTcServer::handleTcReception(uint8_t* spacePacket, size_t pack
   return result;
 }
 
-std::string TcpTmTcServer::getTcpPort() const { return tcpConfig.tcpPort; }
+const std::string& TcpTmTcServer::getTcpPort() const { return tcpConfig.tcpPort; }
 
-void TcpTmTcServer::setSpacePacketParsingOptions(std::vector<uint16_t> validPacketIds) {
-  this->validPacketIds = validPacketIds;
+void TcpTmTcServer::setSpacePacketParsingOptions(std::vector<uint16_t> validPacketIds_) {
+  this->validPacketIds = std::move(validPacketIds_);
 }
 
 TcpTmTcServer::TcpConfig& TcpTmTcServer::getTcpConfigStruct() { return tcpConfig; }
 
 ReturnValue_t TcpTmTcServer::handleTmSending(socket_t connSocket, bool& tmSent) {
   // Access to the FIFO is mutex protected because it is filled by the bridge
-  MutexGuard(tmtcBridge->mutex, tmtcBridge->timeoutType, tmtcBridge->mutexTimeoutMs);
+  MutexGuard mg(tmtcBridge->mutex, tmtcBridge->timeoutType, tmtcBridge->mutexTimeoutMs);
   store_address_t storeId;
   while ((not tmtcBridge->tmFifo->empty()) and
          (tmtcBridge->packetSentCounter < tmtcBridge->sentPacketsPerCycle)) {
@@ -283,7 +284,7 @@ ReturnValue_t TcpTmTcServer::handleTmSending(socket_t connSocket, bool& tmSent)
 #endif
       arrayprinter::print(storeAccessor.data(), storeAccessor.size());
     }
-    int retval = send(connSocket, reinterpret_cast<const char*>(storeAccessor.data()),
+    ssize_t retval = send(connSocket, reinterpret_cast<const char*>(storeAccessor.data()),
                       storeAccessor.size(), tcpConfig.tcpTmFlags);
     if (retval == static_cast<int>(storeAccessor.size())) {
       // Packet sent, clear FIFO entry
@@ -339,6 +340,9 @@ ReturnValue_t TcpTmTcServer::handleTcRingBufferData(size_t availableReadData) {
   size_t foundSize = 0;
   size_t readLen = 0;
   while (readLen < readAmount) {
+    if(spacePacketParser == nullptr) {
+      return HasReturnvaluesIF::RETURN_FAILED;
+    }
     result =
         spacePacketParser->parseSpacePackets(bufPtrPtr, readAmount, startIdx, foundSize, readLen);
     switch (result) {
diff --git a/src/fsfw/osal/common/TcpTmTcServer.h b/src/fsfw/osal/common/TcpTmTcServer.h
index d062a0ce..faf6e0a1 100644
--- a/src/fsfw/osal/common/TcpTmTcServer.h
+++ b/src/fsfw/osal/common/TcpTmTcServer.h
@@ -17,6 +17,7 @@
 #endif
 
 #include <string>
+#include <utility>
 #include <vector>
 
 class TcpTmTcBridge;
@@ -44,7 +45,7 @@ class TcpTmTcServer : public SystemObject, public TcpIpBase, public ExecutableOb
 
   struct TcpConfig {
    public:
-    TcpConfig(std::string tcpPort) : tcpPort(tcpPort) {}
+    explicit TcpConfig(std::string tcpPort) : tcpPort(std::move(tcpPort)) {}
 
     /**
      * Passed to the recv call
@@ -84,7 +85,7 @@ class TcpTmTcServer : public SystemObject, public TcpIpBase, public ExecutableOb
                 size_t ringBufferSize = RING_BUFFER_SIZE,
                 std::string customTcpServerPort = DEFAULT_SERVER_PORT,
                 ReceptionModes receptionMode = ReceptionModes::SPACE_PACKETS);
-  virtual ~TcpTmTcServer();
+  ~TcpTmTcServer() override;
 
   void enableWiretapping(bool enable);
 
@@ -97,10 +98,10 @@ class TcpTmTcServer : public SystemObject, public TcpIpBase, public ExecutableOb
   void setSpacePacketParsingOptions(std::vector<uint16_t> validPacketIds);
 
   ReturnValue_t initialize() override;
-  ReturnValue_t performOperation(uint8_t opCode) override;
+  [[noreturn]] ReturnValue_t performOperation(uint8_t opCode) override;
   ReturnValue_t initializeAfterTaskCreation() override;
 
-  std::string getTcpPort() const;
+  [[nodiscard]] const std::string& getTcpPort() const;
 
  protected:
   StorageManagerIF* tcStore = nullptr;
@@ -115,7 +116,7 @@ class TcpTmTcServer : public SystemObject, public TcpIpBase, public ExecutableOb
 
   ReceptionModes receptionMode;
   TcpConfig tcpConfig;
-  struct sockaddr tcpAddress;
+  struct sockaddr tcpAddress = {};
   socket_t listenerTcpSocket = 0;
 
   MessageQueueId_t targetTcDestination = MessageQueueIF::NO_QUEUE;
diff --git a/src/fsfw/osal/common/UdpTcPollingTask.cpp b/src/fsfw/osal/common/UdpTcPollingTask.cpp
index ab982a3c..38fb1921 100644
--- a/src/fsfw/osal/common/UdpTcPollingTask.cpp
+++ b/src/fsfw/osal/common/UdpTcPollingTask.cpp
@@ -16,11 +16,13 @@
 //! Debugging preprocessor define.
 #define FSFW_UDP_RECV_WIRETAPPING_ENABLED 0
 
+const timeval UdpTcPollingTask::DEFAULT_TIMEOUT = {0, 500000};
+
 UdpTcPollingTask::UdpTcPollingTask(object_id_t objectId, object_id_t tmtcUdpBridge,
                                    size_t maxRecvSize, double timeoutSeconds)
     : SystemObject(objectId), tmtcBridgeId(tmtcUdpBridge) {
-  if (frameSize > 0) {
-    this->frameSize = frameSize;
+  if (maxRecvSize > 0) {
+    this->frameSize = maxRecvSize;
   } else {
     this->frameSize = DEFAULT_MAX_RECV_SIZE;
   }
@@ -31,22 +33,20 @@ UdpTcPollingTask::UdpTcPollingTask(object_id_t objectId, object_id_t tmtcUdpBrid
   receptionBuffer.resize(this->frameSize);
 
   if (timeoutSeconds == -1) {
-    receptionTimeout = DEFAULT_TIMEOUT;
+    receptionTimeout = UdpTcPollingTask::DEFAULT_TIMEOUT;
   } else {
     receptionTimeout = timevalOperations::toTimeval(timeoutSeconds);
   }
 }
 
-UdpTcPollingTask::~UdpTcPollingTask() {}
-
-ReturnValue_t UdpTcPollingTask::performOperation(uint8_t opCode) {
+[[noreturn]] ReturnValue_t UdpTcPollingTask::performOperation(uint8_t opCode) {
   /* Sender Address is cached here. */
-  struct sockaddr senderAddress;
+  struct sockaddr senderAddress {};
   socklen_t senderAddressSize = sizeof(senderAddress);
 
   /* Poll for new UDP datagrams in permanent loop. */
   while (true) {
-    int bytesReceived =
+    ssize_t bytesReceived =
         recvfrom(this->serverSocket, reinterpret_cast<char*>(receptionBuffer.data()), frameSize,
                  receptionFlags, &senderAddress, &senderAddressSize);
     if (bytesReceived == SOCKET_ERROR) {
@@ -70,7 +70,6 @@ ReturnValue_t UdpTcPollingTask::performOperation(uint8_t opCode) {
     }
     tmtcBridge->checkAndSetClientAddress(senderAddress);
   }
-  return HasReturnvaluesIF::RETURN_OK;
 }
 
 ReturnValue_t UdpTcPollingTask::handleSuccessfullTcRead(size_t bytesRead) {
@@ -155,7 +154,7 @@ void UdpTcPollingTask::setTimeout(double timeoutSeconds) {
 #endif
   }
 #elif defined(PLATFORM_UNIX)
-  timeval tval;
+  timeval tval {};
   tval = timevalOperations::toTimeval(timeoutSeconds);
   int result = setsockopt(serverSocket, SOL_SOCKET, SO_RCVTIMEO, &tval, sizeof(receptionTimeout));
   if (result == -1) {
diff --git a/src/fsfw/osal/common/UdpTcPollingTask.h b/src/fsfw/osal/common/UdpTcPollingTask.h
index afcd32a1..894716d7 100644
--- a/src/fsfw/osal/common/UdpTcPollingTask.h
+++ b/src/fsfw/osal/common/UdpTcPollingTask.h
@@ -21,11 +21,11 @@ class UdpTcPollingTask : public TcpIpBase, public SystemObject, public Executabl
  public:
   static constexpr size_t DEFAULT_MAX_RECV_SIZE = 1500;
   //! 0.5  default milliseconds timeout for now.
-  static constexpr timeval DEFAULT_TIMEOUT = {0, 500};
+  static const timeval DEFAULT_TIMEOUT;
 
   UdpTcPollingTask(object_id_t objectId, object_id_t tmtcUdpBridge, size_t maxRecvSize = 0,
                    double timeoutSeconds = -1);
-  virtual ~UdpTcPollingTask();
+  ~UdpTcPollingTask() override = default;
 
   /**
    * Turn on optional timeout for UDP polling. In the default mode,
@@ -34,9 +34,9 @@ class UdpTcPollingTask : public TcpIpBase, public SystemObject, public Executabl
    */
   void setTimeout(double timeoutSeconds);
 
-  virtual ReturnValue_t performOperation(uint8_t opCode) override;
-  virtual ReturnValue_t initialize() override;
-  virtual ReturnValue_t initializeAfterTaskCreation() override;
+  [[noreturn]] ReturnValue_t performOperation(uint8_t opCode) override;
+  ReturnValue_t initialize() override;
+  ReturnValue_t initializeAfterTaskCreation() override;
 
  protected:
   StorageManagerIF* tcStore = nullptr;
@@ -51,7 +51,7 @@ class UdpTcPollingTask : public TcpIpBase, public SystemObject, public Executabl
   std::vector<uint8_t> receptionBuffer;
 
   size_t frameSize = 0;
-  timeval receptionTimeout;
+  timeval receptionTimeout{};
 
   ReturnValue_t handleSuccessfullTcRead(size_t bytesRead);
 };
diff --git a/src/fsfw/osal/common/UdpTmTcBridge.cpp b/src/fsfw/osal/common/UdpTmTcBridge.cpp
index 0efe1c74..6089f266 100644
--- a/src/fsfw/osal/common/UdpTmTcBridge.cpp
+++ b/src/fsfw/osal/common/UdpTmTcBridge.cpp
@@ -20,13 +20,13 @@
 const std::string UdpTmTcBridge::DEFAULT_SERVER_PORT = tcpip::DEFAULT_SERVER_PORT;
 
 UdpTmTcBridge::UdpTmTcBridge(object_id_t objectId, object_id_t tcDestination,
-                             std::string udpServerPort, object_id_t tmStoreId,
+                             const std::string& udpServerPort_, object_id_t tmStoreId,
                              object_id_t tcStoreId)
     : TmTcBridge(objectId, tcDestination, tmStoreId, tcStoreId) {
-  if (udpServerPort == "") {
-    this->udpServerPort = DEFAULT_SERVER_PORT;
+  if (udpServerPort_.empty()) {
+    udpServerPort = DEFAULT_SERVER_PORT;
   } else {
-    this->udpServerPort = udpServerPort;
+    udpServerPort = udpServerPort_;
   }
 
   mutex = MutexFactory::instance()->createMutex();
@@ -117,7 +117,7 @@ ReturnValue_t UdpTmTcBridge::sendTm(const uint8_t *data, size_t dataLen) {
   tcpip::printAddress(&clientAddress);
 #endif
 
-  int bytesSent = sendto(serverSocket, reinterpret_cast<const char *>(data), dataLen, flags,
+  ssize_t bytesSent = sendto(serverSocket, reinterpret_cast<const char *>(data), dataLen, flags,
                          &clientAddress, clientAddressLen);
   if (bytesSent == SOCKET_ERROR) {
 #if FSFW_CPP_OSTREAM_ENABLED == 1
@@ -150,7 +150,7 @@ void UdpTmTcBridge::checkAndSetClientAddress(sockaddr &newAddress) {
   clientAddressLen = sizeof(clientAddress);
 }
 
-void UdpTmTcBridge::setMutexProperties(MutexIF::TimeoutType timeoutType, dur_millis_t timeoutMs) {
-  this->timeoutType = timeoutType;
-  this->mutexTimeoutMs = timeoutMs;
+void UdpTmTcBridge::setMutexProperties(MutexIF::TimeoutType timeoutType_, dur_millis_t timeoutMs) {
+  timeoutType = timeoutType_;
+  mutexTimeoutMs = timeoutMs;
 }
diff --git a/src/fsfw/osal/common/UdpTmTcBridge.h b/src/fsfw/osal/common/UdpTmTcBridge.h
index 78843ccd..b0a67430 100644
--- a/src/fsfw/osal/common/UdpTmTcBridge.h
+++ b/src/fsfw/osal/common/UdpTmTcBridge.h
@@ -29,10 +29,10 @@ class UdpTmTcBridge : public TmTcBridge, public TcpIpBase {
   /* The ports chosen here should not be used by any other process. */
   static const std::string DEFAULT_SERVER_PORT;
 
-  UdpTmTcBridge(object_id_t objectId, object_id_t tcDestination, std::string udpServerPort = "",
+  UdpTmTcBridge(object_id_t objectId, object_id_t tcDestination, const std::string& udpServerPort = "",
                 object_id_t tmStoreId = objects::TM_STORE,
                 object_id_t tcStoreId = objects::TC_STORE);
-  virtual ~UdpTmTcBridge();
+  ~UdpTmTcBridge() override;
 
   /**
    * Set properties of internal mutex.
@@ -46,12 +46,12 @@ class UdpTmTcBridge : public TmTcBridge, public TcpIpBase {
   std::string getUdpPort() const;
 
  protected:
-  virtual ReturnValue_t sendTm(const uint8_t* data, size_t dataLen) override;
+  ReturnValue_t sendTm(const uint8_t* data, size_t dataLen) override;
 
  private:
   std::string udpServerPort;
 
-  struct sockaddr clientAddress;
+  struct sockaddr clientAddress = {};
   socklen_t clientAddressLen = 0;
 
   //! Access to the client address is mutex protected as it is set by another task.
diff --git a/src/fsfw/osal/host/CMakeLists.txt b/src/fsfw/osal/host/CMakeLists.txt
index 2d29ce5d..8b11a531 100644
--- a/src/fsfw/osal/host/CMakeLists.txt
+++ b/src/fsfw/osal/host/CMakeLists.txt
@@ -1,24 +1,27 @@
-target_sources(${LIB_FSFW_NAME} 
-	PRIVATE 
-		Clock.cpp
-		FixedTimeslotTask.cpp
-		MessageQueue.cpp
-		Mutex.cpp
-		MutexFactory.cpp
-		PeriodicTask.cpp
-		QueueFactory.cpp
-		QueueMapManager.cpp
-		SemaphoreFactory.cpp
-		TaskFactory.cpp
-		taskHelpers.cpp
+target_sources(${LIB_FSFW_NAME} PRIVATE
+  Clock.cpp
+  FixedTimeslotTask.cpp
+  MessageQueue.cpp
+  Mutex.cpp
+  MutexFactory.cpp
+  PeriodicTask.cpp
+  QueueFactory.cpp
+  QueueMapManager.cpp
+  SemaphoreFactory.cpp
+  TaskFactory.cpp
+  taskHelpers.cpp
 )
 
 if(UNIX)
-	find_package(Threads REQUIRED)
-	
-	target_link_libraries(${LIB_FSFW_NAME} 
-	PRIVATE
-		rt
-		${CMAKE_THREAD_LIBS_INIT}
-	)
+  find_package(Threads REQUIRED)
+
+  target_link_libraries(${LIB_FSFW_NAME} PRIVATE
+    ${CMAKE_THREAD_LIBS_INIT}
+  )
+  if(NOT APPLE)
+    target_link_libraries(${LIB_FSFW_NAME} PRIVATE
+      rt
+      )
+  endif()
+
 endif()
\ No newline at end of file
diff --git a/src/fsfw/osal/linux/CMakeLists.txt b/src/fsfw/osal/linux/CMakeLists.txt
index 679b2931..2e88d6d0 100644
--- a/src/fsfw/osal/linux/CMakeLists.txt
+++ b/src/fsfw/osal/linux/CMakeLists.txt
@@ -1,29 +1,29 @@
 target_sources(${LIB_FSFW_NAME} PRIVATE
-    Clock.cpp
-    BinarySemaphore.cpp
-    CountingSemaphore.cpp
-    FixedTimeslotTask.cpp
-    InternalErrorCodes.cpp
-    MessageQueue.cpp
-    Mutex.cpp
-    MutexFactory.cpp
-    PeriodicPosixTask.cpp
-    PosixThread.cpp
-    QueueFactory.cpp
-    SemaphoreFactory.cpp
-    TaskFactory.cpp
-    tcpipHelpers.cpp
-    unixUtility.cpp
-)
+  Clock.cpp
+  BinarySemaphore.cpp
+  CountingSemaphore.cpp
+  FixedTimeslotTask.cpp
+  InternalErrorCodes.cpp
+  MessageQueue.cpp
+  Mutex.cpp
+  MutexFactory.cpp
+  PeriodicPosixTask.cpp
+  PosixThread.cpp
+  QueueFactory.cpp
+  SemaphoreFactory.cpp
+  TaskFactory.cpp
+  tcpipHelpers.cpp
+  unixUtility.cpp
+  )
 
 find_package(Threads REQUIRED)
 
-target_link_libraries(${LIB_FSFW_NAME} PRIVATE
-    ${CMAKE_THREAD_LIBS_INIT}
+target_link_libraries(${LIB_FSFW_NAME} PUBLIC
+  ${CMAKE_THREAD_LIBS_INIT}
+  )
+
+if(NOT APPLE)
+  target_link_libraries(${LIB_FSFW_NAME} PUBLIC
     rt
-)
-
-target_link_libraries(${LIB_FSFW_NAME} INTERFACE
-    ${CMAKE_THREAD_LIBS_INIT}
-)
-
+  )
+endif()
diff --git a/src/fsfw/power/Fuse.h b/src/fsfw/power/Fuse.h
index e6f9c149..787fa38d 100644
--- a/src/fsfw/power/Fuse.h
+++ b/src/fsfw/power/Fuse.h
@@ -54,7 +54,7 @@ class Fuse : public SystemObject,
 
   ReturnValue_t check();
   uint8_t getFuseId() const;
-  ReturnValue_t initialize();
+  ReturnValue_t initialize() override;
   DeviceList devices;
   ReturnValue_t serialize(uint8_t **buffer, size_t *size, size_t maxSize,
                           SerializeIF::Endianness streamEndianness) const override;
diff --git a/src/fsfw/pus/CService201HealthCommanding.cpp b/src/fsfw/pus/CService201HealthCommanding.cpp
index 4d9806f9..f6c49cd3 100644
--- a/src/fsfw/pus/CService201HealthCommanding.cpp
+++ b/src/fsfw/pus/CService201HealthCommanding.cpp
@@ -13,8 +13,6 @@ CService201HealthCommanding::CService201HealthCommanding(object_id_t objectId, u
     : CommandingServiceBase(objectId, apid, serviceId, numParallelCommands, commandTimeoutSeconds) {
 }
 
-CService201HealthCommanding::~CService201HealthCommanding() {}
-
 ReturnValue_t CService201HealthCommanding::isValidSubservice(uint8_t subservice) {
   switch (subservice) {
     case (Subservice::COMMAND_SET_HEALTH):
@@ -43,8 +41,8 @@ ReturnValue_t CService201HealthCommanding::getMessageQueueAndObject(uint8_t subs
 }
 
 ReturnValue_t CService201HealthCommanding::checkInterfaceAndAcquireMessageQueue(
-    MessageQueueId_t *messageQueueToSet, object_id_t *objectId) {
-  HasHealthIF *destination = ObjectManager::instance()->get<HasHealthIF>(*objectId);
+    MessageQueueId_t *messageQueueToSet, const object_id_t *objectId) {
+  auto *destination = ObjectManager::instance()->get<HasHealthIF>(*objectId);
   if (destination == nullptr) {
     return CommandingServiceBase::INVALID_OBJECT;
   }
@@ -77,6 +75,10 @@ ReturnValue_t CService201HealthCommanding::prepareCommand(CommandMessage *messag
       HealthMessage::setHealthMessage(message, HealthMessage::HEALTH_ANNOUNCE_ALL);
       break;
     }
+    default: {
+      // Should never happen, subservice was already checked
+      result = RETURN_FAILED;
+    }
   }
   return result;
 }
@@ -95,10 +97,9 @@ ReturnValue_t CService201HealthCommanding::handleReply(const CommandMessage *rep
 }
 
 // Not used for now, health state already reported by event
-ReturnValue_t CService201HealthCommanding::prepareHealthSetReply(const CommandMessage *reply) {
-  prepareHealthSetReply(reply);
-  uint8_t health = static_cast<uint8_t>(HealthMessage::getHealth(reply));
-  uint8_t oldHealth = static_cast<uint8_t>(HealthMessage::getOldHealth(reply));
+[[maybe_unused]] ReturnValue_t CService201HealthCommanding::prepareHealthSetReply(const CommandMessage *reply) {
+  auto health = static_cast<uint8_t>(HealthMessage::getHealth(reply));
+  auto oldHealth = static_cast<uint8_t>(HealthMessage::getOldHealth(reply));
   HealthSetReply healthSetReply(health, oldHealth);
   return sendTmPacket(Subservice::REPLY_HEALTH_SET, &healthSetReply);
 }
diff --git a/src/fsfw/pus/CService201HealthCommanding.h b/src/fsfw/pus/CService201HealthCommanding.h
index 5e52ab39..7ffa06d2 100644
--- a/src/fsfw/pus/CService201HealthCommanding.h
+++ b/src/fsfw/pus/CService201HealthCommanding.h
@@ -1,7 +1,7 @@
 #ifndef FSFW_PUS_CSERVICE201HEALTHCOMMANDING_H_
 #define FSFW_PUS_CSERVICE201HEALTHCOMMANDING_H_
 
-#include "../tmtcservices/CommandingServiceBase.h"
+#include "fsfw/tmtcservices/CommandingServiceBase.h"
 
 /**
  * @brief   Custom PUS service to set health of all objects
@@ -21,7 +21,7 @@ class CService201HealthCommanding : public CommandingServiceBase {
  public:
   CService201HealthCommanding(object_id_t objectId, uint16_t apid, uint8_t serviceId,
                               uint8_t numParallelCommands = 4, uint16_t commandTimeoutSeconds = 60);
-  virtual ~CService201HealthCommanding();
+  ~CService201HealthCommanding() override = default;
 
  protected:
   /* CSB abstract function implementations */
@@ -38,12 +38,10 @@ class CService201HealthCommanding : public CommandingServiceBase {
                             bool *isStep) override;
 
  private:
-  ReturnValue_t checkAndAcquireTargetID(object_id_t *objectIdToSet, const uint8_t *tcData,
-                                        size_t tcDataLen);
-  ReturnValue_t checkInterfaceAndAcquireMessageQueue(MessageQueueId_t *MessageQueueToSet,
-                                                     object_id_t *objectId);
+  static ReturnValue_t checkInterfaceAndAcquireMessageQueue(MessageQueueId_t *MessageQueueToSet,
+                                                     const object_id_t *objectId);
 
-  ReturnValue_t prepareHealthSetReply(const CommandMessage *reply);
+  [[maybe_unused]] ReturnValue_t prepareHealthSetReply(const CommandMessage *reply);
 
   enum Subservice {
     //! [EXPORT] : [TC] Set health of target object
diff --git a/src/fsfw/pus/Service3Housekeeping.h b/src/fsfw/pus/Service3Housekeeping.h
index c1928891..70f15762 100644
--- a/src/fsfw/pus/Service3Housekeeping.h
+++ b/src/fsfw/pus/Service3Housekeeping.h
@@ -43,7 +43,7 @@ class Service3Housekeeping : public CommandingServiceBase, public AcceptsHkPacke
                             CommandMessage* optionalNextCommand, object_id_t objectId,
                             bool* isStep) override;
 
-  virtual MessageQueueId_t getHkQueue() const;
+  virtual MessageQueueId_t getHkQueue() const override;
 
  private:
   enum class Subservice {
diff --git a/src/fsfw/subsystem/Subsystem.cpp b/src/fsfw/subsystem/Subsystem.cpp
index a837bf83..27e6ae8e 100644
--- a/src/fsfw/subsystem/Subsystem.cpp
+++ b/src/fsfw/subsystem/Subsystem.cpp
@@ -30,11 +30,11 @@ ReturnValue_t Subsystem::checkSequence(HybridIterator<ModeListEntry> iter,
     return FALLBACK_SEQUENCE_DOES_NOT_EXIST;
   }
 
-  if (iter.value == NULL) {
+  if (iter.value == nullptr) {
     return NO_TARGET_TABLE;
   }
 
-  for (; iter.value != NULL; ++iter) {
+  for (; iter.value != nullptr; ++iter) {
     if (!existsModeTable(iter->getTableId())) {
       return TABLE_DOES_NOT_EXIST;
     } else {
@@ -66,13 +66,18 @@ HybridIterator<ModeListEntry> Subsystem::getCurrentTable() {
 void Subsystem::performChildOperation() {
   if (isInTransition) {
     if (commandsOutstanding <= 0) {  // all children of the current table were commanded and replied
-      if (currentSequenceIterator.value == NULL) {  // we're through with this sequence
+      if (currentSequenceIterator.value == nullptr) {  // we're through with this sequence
         if (checkStateAgainstTable(currentTargetTable, targetSubmode) == RETURN_OK) {
           setMode(targetMode, targetSubmode);
           isInTransition = false;
           return;
         } else {
-          transitionFailed(TARGET_TABLE_NOT_REACHED, getSequence(targetMode)->getTableId());
+          Mode_t tableId = 0;
+          auto seq = getSequence(targetMode);
+          if (seq.value != nullptr) {
+            tableId = seq->getTableId();
+          }
+          transitionFailed(TARGET_TABLE_NOT_REACHED, tableId);
           return;
         }
       }
@@ -248,10 +253,13 @@ ReturnValue_t Subsystem::handleCommandMessage(CommandMessage *message) {
     case ModeSequenceMessage::READ_TABLE: {
       ReturnValue_t result;
       Mode_t table = ModeSequenceMessage::getSequenceId(message);
-      EntryPointer *entry = NULL;
+      EntryPointer *entry = nullptr;
       result = modeTables.find(table, &entry);
-      if (result != RETURN_OK) {
+      if (result != RETURN_OK or entry == nullptr) {
         replyToCommand(result, 0);
+        if (entry == nullptr) {
+          return result;
+        }
       }
 
       SerializeIF *elements[2];
@@ -299,6 +307,11 @@ void Subsystem::replyToCommand(ReturnValue_t status, uint32_t parameter) {
   }
 }
 
+ReturnValue_t Subsystem::addSequence(SequenceEntry sequence) {
+  return addSequence(sequence.table, sequence.mode, sequence.fallbackMode, sequence.inStore,
+                     sequence.preInit);
+}
+
 ReturnValue_t Subsystem::addSequence(ArrayList<ModeListEntry> *sequence, Mode_t id,
                                      Mode_t fallbackSequence, bool inStore, bool preInit) {
   ReturnValue_t result;
@@ -342,6 +355,10 @@ ReturnValue_t Subsystem::addSequence(ArrayList<ModeListEntry> *sequence, Mode_t
   return result;
 }
 
+ReturnValue_t Subsystem::addTable(TableEntry table) {
+  return addTable(table.table, table.mode, table.inStore, table.preInit);
+}
+
 ReturnValue_t Subsystem::addTable(ArrayList<ModeListEntry> *table, Mode_t id, bool inStore,
                                   bool preInit) {
   ReturnValue_t result;
@@ -450,6 +467,7 @@ ReturnValue_t Subsystem::initialize() {
   }
 
   mode = initialMode;
+  submode = initSubmode;
 
   return RETURN_OK;
 }
@@ -587,7 +605,10 @@ ReturnValue_t Subsystem::checkObjectConnections() {
   return RETURN_OK;
 }
 
-void Subsystem::setInitialMode(Mode_t mode) { initialMode = mode; }
+void Subsystem::setInitialMode(Mode_t mode, Submode_t submode) {
+  this->initialMode = mode;
+  this->initSubmode = submode;
+}
 
 void Subsystem::cantKeepMode() {
   ReturnValue_t result;
diff --git a/src/fsfw/subsystem/Subsystem.h b/src/fsfw/subsystem/Subsystem.h
index 2c78c8cd..855c8f7a 100644
--- a/src/fsfw/subsystem/Subsystem.h
+++ b/src/fsfw/subsystem/Subsystem.h
@@ -1,16 +1,37 @@
 #ifndef FSFW_SUBSYSTEM_SUBSYSTEM_H_
 #define FSFW_SUBSYSTEM_SUBSYSTEM_H_
 
-#include <FSFWConfig.h>
-
 #include "../container/FixedArrayList.h"
 #include "../container/FixedMap.h"
 #include "../container/HybridIterator.h"
 #include "../container/SinglyLinkedList.h"
 #include "../serialize/SerialArrayListAdapter.h"
 #include "SubsystemBase.h"
+#include "fsfw/FSFW.h"
 #include "modes/ModeDefinitions.h"
 
+struct TableSequenceBase {
+ public:
+  TableSequenceBase(Mode_t mode, ArrayList<ModeListEntry> *table) : mode(mode), table(table){};
+  Mode_t mode;
+  ArrayList<ModeListEntry> *table;
+  bool inStore = false;
+  bool preInit = true;
+};
+
+struct TableEntry : public TableSequenceBase {
+ public:
+  TableEntry(Mode_t mode, ArrayList<ModeListEntry> *table) : TableSequenceBase(mode, table){};
+};
+
+struct SequenceEntry : public TableSequenceBase {
+ public:
+  SequenceEntry(Mode_t mode, ArrayList<ModeListEntry> *table, Mode_t fallbackMode)
+      : TableSequenceBase(mode, table), fallbackMode(fallbackMode) {}
+
+  Mode_t fallbackMode;
+};
+
 /**
  * @brief   TODO: documentation missing
  * @details
@@ -45,13 +66,15 @@ class Subsystem : public SubsystemBase, public HasModeSequenceIF {
             uint32_t maxNumberOfTables);
   virtual ~Subsystem();
 
+  ReturnValue_t addSequence(SequenceEntry sequence);
   ReturnValue_t addSequence(ArrayList<ModeListEntry> *sequence, Mode_t id, Mode_t fallbackSequence,
                             bool inStore = true, bool preInit = true);
 
+  ReturnValue_t addTable(TableEntry table);
   ReturnValue_t addTable(ArrayList<ModeListEntry> *table, Mode_t id, bool inStore = true,
                          bool preInit = true);
 
-  void setInitialMode(Mode_t mode);
+  void setInitialMode(Mode_t mode, Submode_t submode = SUBMODE_NONE);
 
   virtual ReturnValue_t initialize() override;
 
@@ -90,6 +113,7 @@ class Subsystem : public SubsystemBase, public HasModeSequenceIF {
   Submode_t targetSubmode;
 
   Mode_t initialMode = 0;
+  Submode_t initSubmode = SUBMODE_NONE;
 
   HybridIterator<ModeListEntry> currentSequenceIterator;
 
@@ -127,18 +151,18 @@ class Subsystem : public SubsystemBase, public HasModeSequenceIF {
 
   ReturnValue_t deleteTable(Mode_t id);
 
-  virtual void performChildOperation();
+  virtual void performChildOperation() override;
 
-  virtual ReturnValue_t handleCommandMessage(CommandMessage *message);
+  virtual ReturnValue_t handleCommandMessage(CommandMessage *message) override;
 
   bool isFallbackSequence(Mode_t SequenceId);
 
   bool isTableUsed(Mode_t tableId);
 
   virtual ReturnValue_t checkModeCommand(Mode_t mode, Submode_t submode,
-                                         uint32_t *msToReachTheMode);
+                                         uint32_t *msToReachTheMode) override;
 
-  virtual void startTransition(Mode_t mode, Submode_t submode);
+  virtual void startTransition(Mode_t mode, Submode_t submode) override;
 
   void sendSerializablesAsCommandMessage(Command_t command, SerializeIF **elements, uint8_t count);
 
diff --git a/src/fsfw/subsystem/SubsystemBase.h b/src/fsfw/subsystem/SubsystemBase.h
index 8cfd5be0..52f9891e 100644
--- a/src/fsfw/subsystem/SubsystemBase.h
+++ b/src/fsfw/subsystem/SubsystemBase.h
@@ -123,15 +123,15 @@ class SubsystemBase : public SystemObject,
   virtual void performChildOperation() = 0;
 
   virtual ReturnValue_t checkModeCommand(Mode_t mode, Submode_t submode,
-                                         uint32_t *msToReachTheMode) = 0;
+                                         uint32_t *msToReachTheMode) override = 0;
 
-  virtual void startTransition(Mode_t mode, Submode_t submode) = 0;
+  virtual void startTransition(Mode_t mode, Submode_t submode) override = 0;
 
-  virtual void getMode(Mode_t *mode, Submode_t *submode);
+  virtual void getMode(Mode_t *mode, Submode_t *submode) override;
 
-  virtual void setToExternalControl();
+  virtual void setToExternalControl() override;
 
-  virtual void announceMode(bool recursive);
+  virtual void announceMode(bool recursive) override;
 
   virtual void modeChanged();
 };
diff --git a/src/fsfw/timemanager/CCSDSTime.cpp b/src/fsfw/timemanager/CCSDSTime.cpp
index 9ebd1d79..1f84dd03 100644
--- a/src/fsfw/timemanager/CCSDSTime.cpp
+++ b/src/fsfw/timemanager/CCSDSTime.cpp
@@ -6,10 +6,6 @@
 
 #include "fsfw/FSFW.h"
 
-CCSDSTime::CCSDSTime() {}
-
-CCSDSTime::~CCSDSTime() {}
-
 ReturnValue_t CCSDSTime::convertToCcsds(Ccs_seconds* to, const Clock::TimeOfDay_t* from) {
   ReturnValue_t result = checkTimeOfDay(from);
   if (result != RETURN_OK) {
@@ -428,7 +424,7 @@ ReturnValue_t CCSDSTime::convertFromCUC(timeval* to, const uint8_t* from, size_t
   from++;
   ReturnValue_t result = convertFromCUC(to, pField, from, foundLength, maxLength - 1);
   if (result == HasReturnvaluesIF::RETURN_OK) {
-    if (foundLength != NULL) {
+    if (foundLength != nullptr) {
       *foundLength += 1;
     }
   }
@@ -588,18 +584,18 @@ ReturnValue_t CCSDSTime::convertFromCUC(timeval* to, uint8_t pField, const uint8
   uint8_t nCoarse = ((pField & 0b1100) >> 2) + 1;
   uint8_t nFine = (pField & 0b11);
   size_t totalLength = nCoarse + nFine;
-  if (foundLength != NULL) {
+  if (foundLength != nullptr) {
     *foundLength = totalLength;
   }
   if (totalLength > maxLength) {
     return LENGTH_MISMATCH;
   }
-  for (int count = 0; count < nCoarse; count++) {
-    secs += *from << ((nCoarse * 8 - 8) * (1 + count));
+  for (int count = nCoarse; count > 0; count--) {
+    secs += *from << (count * 8 - 8);
     from++;
   }
-  for (int count = 0; count < nFine; count++) {
-    subSeconds += *from << ((nFine * 8 - 8) * (1 + count));
+  for (int count = nFine; count > 0; count--) {
+    subSeconds += *from << (count * 8 - 8);
     from++;
   }
   // Move to POSIX epoch.
diff --git a/src/fsfw/timemanager/CCSDSTime.h b/src/fsfw/timemanager/CCSDSTime.h
index 19c980d0..2a2316af 100644
--- a/src/fsfw/timemanager/CCSDSTime.h
+++ b/src/fsfw/timemanager/CCSDSTime.h
@@ -161,18 +161,37 @@ class CCSDSTime : public HasReturnvaluesIF {
    */
   static ReturnValue_t convertFromCcsds(timeval *to, uint8_t const *from, size_t *foundLength,
                                         size_t maxLength);
-
+  /**
+   * @brief Currently unsupported conversion due to leapseconds
+   *
+   * @param to Time Of Day (UTC)
+   * @param from Buffer to take the CUC from
+   * @param length Length of buffer
+   * @return ReturnValue_t UNSUPPORTED_TIME_FORMAT in any case ATM
+   */
   static ReturnValue_t convertFromCUC(Clock::TimeOfDay_t *to, uint8_t const *from, uint8_t length);
-
+  /**
+   * @brief Converts from CCSDS CUC to timeval
+   *
+   * If input is CCSDS Epoch this is TAI! -> No leapsecond support.
+   *
+   * Currently, it only supports seconds + 2 Byte Subseconds (1/65536 seconds)
+   *
+   *
+   * @param to Timeval to write the result to
+   * @param from Buffer to read from
+   * @param foundLength Length found by this function (can be nullptr if unused)
+   * @param maxLength Max length of the buffer to be read
+   * @return ReturnValue_t - RETURN_OK if successful
+   *                       - LENGTH_MISMATCH if expected length is larger than maxLength
+   */
   static ReturnValue_t convertFromCUC(timeval *to, uint8_t const *from, size_t *foundLength,
                                       size_t maxLength);
-
   static ReturnValue_t convertFromCUC(timeval *to, uint8_t pField, uint8_t const *from,
                                       size_t *foundLength, size_t maxLength);
 
   static ReturnValue_t convertFromCCS(timeval *to, uint8_t const *from, size_t *foundLength,
                                       size_t maxLength);
-
   static ReturnValue_t convertFromCCS(timeval *to, uint8_t pField, uint8_t const *from,
                                       size_t *foundLength, size_t maxLength);
 
@@ -192,8 +211,8 @@ class CCSDSTime : public HasReturnvaluesIF {
   static uint32_t subsecondsToMicroseconds(uint16_t subseconds);
 
  private:
-  CCSDSTime();
-  virtual ~CCSDSTime();
+  CCSDSTime(){};
+  virtual ~CCSDSTime(){};
   /**
    * checks a ccs time stream for validity
    *
diff --git a/src/fsfw/tmtcpacket/SpacePacket.cpp b/src/fsfw/tmtcpacket/SpacePacket.cpp
index c8ebbd97..16d968fb 100644
--- a/src/fsfw/tmtcpacket/SpacePacket.cpp
+++ b/src/fsfw/tmtcpacket/SpacePacket.cpp
@@ -19,8 +19,8 @@ SpacePacket::SpacePacket(uint16_t packetDataLength, bool isTelecommand, uint16_t
 SpacePacket::~SpacePacket(void) {}
 
 bool SpacePacket::addWholeData(const uint8_t* p_Data, uint32_t packet_size) {
-  if (packet_size <= sizeof(this->data)) {
-    memcpy(&this->localData.byteStream, p_Data, packet_size);
+  if (packet_size <= sizeof(this->localData)) {
+    memcpy(this->localData.byteStream, p_Data, packet_size);
     return true;
   } else {
     return false;
diff --git a/src/fsfw/tmtcservices/CommandingServiceBase.h b/src/fsfw/tmtcservices/CommandingServiceBase.h
index 0ae19505..4dcad024 100644
--- a/src/fsfw/tmtcservices/CommandingServiceBase.h
+++ b/src/fsfw/tmtcservices/CommandingServiceBase.h
@@ -95,7 +95,7 @@ class CommandingServiceBase : public SystemObject,
    */
   virtual ReturnValue_t performOperation(uint8_t opCode) override;
 
-  virtual uint16_t getIdentifier();
+  virtual uint16_t getIdentifier() override;
 
   /**
    * Returns the requestQueue MessageQueueId_t
@@ -104,7 +104,7 @@ class CommandingServiceBase : public SystemObject,
    *
    * @return requestQueue messageQueueId_t
    */
-  virtual MessageQueueId_t getRequestQueue();
+  virtual MessageQueueId_t getRequestQueue() override;
 
   /**
    * Returns the commandQueue MessageQueueId_t
@@ -166,7 +166,7 @@ class CommandingServiceBase : public SystemObject,
    * @param objectId Target object ID
    * @return
    * - @c RETURN_OK to generate a verification start message
-   * - @c EXECUTION_COMPELTE Fire-and-forget command. Generate a completion
+   * - @c EXECUTION_COMPLETE Fire-and-forget command. Generate a completion
    *      verification message.
    * - @c Anything else rejects the packets and generates a start failure
    *      verification.
diff --git a/tests/src/fsfw_tests/unit/timemanager/TestCCSDSTime.cpp b/tests/src/fsfw_tests/unit/timemanager/TestCCSDSTime.cpp
index a43ff8ab..e96ddfc9 100644
--- a/tests/src/fsfw_tests/unit/timemanager/TestCCSDSTime.cpp
+++ b/tests/src/fsfw_tests/unit/timemanager/TestCCSDSTime.cpp
@@ -179,6 +179,27 @@ TEST_CASE("CCSDSTime Tests", "[TestCCSDSTime]") {
     CHECK(todFromCCSDS.second == time.second);
     CHECK(todFromCCSDS.usecond == 123000);
   }
+  SECTION("CUC") {
+    timeval to;
+    // seconds = 0x771E960F, microseconds = 0x237
+    // microseconds = 567000
+    // This gives 37158.912 1/65536 seconds -> rounded to 37159 -> 0x9127
+    // This results in -> 567001 us
+    std::array<uint8_t, 7> cucBuffer = {
+        CCSDSTime::P_FIELD_CUC_6B_CCSDS, 0x77, 0x1E, 0x96, 0x0F, 0x91, 0x27};
+    size_t foundLength = 0;
+    auto result = CCSDSTime::convertFromCUC(&to, cucBuffer.data(), &foundLength, cucBuffer.size());
+    REQUIRE(result == HasReturnvaluesIF::RETURN_OK);
+    REQUIRE(foundLength == 7);
+    REQUIRE(to.tv_sec == 1619801999);  // TAI (no leap seconds)
+    REQUIRE(to.tv_usec == 567001);
+
+    Clock::TimeOfDay_t tod;
+    result = CCSDSTime::convertFromCUC(&tod, cucBuffer.data(), cucBuffer.size());
+    // This test must be changed if this is ever going to be implemented
+    REQUIRE(result == CCSDSTime::UNSUPPORTED_TIME_FORMAT);
+  }
+
   SECTION("CCSDS Failures") {
     Clock::TimeOfDay_t time;
     time.year = 2020;