diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5181a862e..3d28c5c6c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -54,6 +54,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - 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
+  configuration fails, the function will exit prematurely with a dedicated error code
+  PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/602
 
 # [v4.0.0]
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d8ca812e0..bfe3da841 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,14 +10,15 @@ 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"
 )
 
@@ -76,9 +77,7 @@ 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 +122,22 @@ 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")
@@ -387,7 +401,7 @@ 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 9df67fc82..0eb98fbb1 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 d1459e52f..6abf56366 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/devicehandlers/MgmLIS3MDLHandler.cpp b/hal/src/fsfw_hal/devicehandlers/MgmLIS3MDLHandler.cpp
index 52b6dc07b..644b488dd 100644
--- a/hal/src/fsfw_hal/devicehandlers/MgmLIS3MDLHandler.cpp
+++ b/hal/src/fsfw_hal/devicehandlers/MgmLIS3MDLHandler.cpp
@@ -1,9 +1,9 @@
 #include "MgmLIS3MDLHandler.h"
 
-#include "fsfw/datapool/PoolReadGuard.h"
-
 #include <cmath>
 
+#include "fsfw/datapool/PoolReadGuard.h"
+
 MgmLIS3MDLHandler::MgmLIS3MDLHandler(object_id_t objectId, object_id_t deviceCommunication,
                                      CookieIF *comCookie, uint32_t transitionDelay)
     : DeviceHandlerBase(objectId, deviceCommunication, comCookie),
diff --git a/hal/src/fsfw_hal/linux/CMakeLists.txt b/hal/src/fsfw_hal/linux/CMakeLists.txt
index 56d4bf489..f6d1a4603 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/gpio/LinuxLibgpioIF.cpp b/hal/src/fsfw_hal/linux/gpio/LinuxLibgpioIF.cpp
index 3b9a21f7f..f46ad3865 100644
--- a/hal/src/fsfw_hal/linux/gpio/LinuxLibgpioIF.cpp
+++ b/hal/src/fsfw_hal/linux/gpio/LinuxLibgpioIF.cpp
@@ -44,6 +44,7 @@ ReturnValue_t LinuxLibgpioIF::addGpios(GpioCookie* gpioCookie) {
 }
 
 ReturnValue_t LinuxLibgpioIF::configureGpios(GpioMap& mapToAdd) {
+  ReturnValue_t result = RETURN_OK;
   for (auto& gpioConfig : mapToAdd) {
     auto& gpioType = gpioConfig.second->gpioType;
     switch (gpioType) {
@@ -55,7 +56,7 @@ ReturnValue_t LinuxLibgpioIF::configureGpios(GpioMap& mapToAdd) {
         if (regularGpio == nullptr) {
           return GPIO_INVALID_INSTANCE;
         }
-        configureGpioByChip(gpioConfig.first, *regularGpio);
+        result = configureGpioByChip(gpioConfig.first, *regularGpio);
         break;
       }
       case (gpio::GpioTypes::GPIO_REGULAR_BY_LABEL): {
@@ -63,7 +64,7 @@ ReturnValue_t LinuxLibgpioIF::configureGpios(GpioMap& mapToAdd) {
         if (regularGpio == nullptr) {
           return GPIO_INVALID_INSTANCE;
         }
-        configureGpioByLabel(gpioConfig.first, *regularGpio);
+        result = configureGpioByLabel(gpioConfig.first, *regularGpio);
         break;
       }
       case (gpio::GpioTypes::GPIO_REGULAR_BY_LINE_NAME): {
@@ -71,7 +72,7 @@ ReturnValue_t LinuxLibgpioIF::configureGpios(GpioMap& mapToAdd) {
         if (regularGpio == nullptr) {
           return GPIO_INVALID_INSTANCE;
         }
-        configureGpioByLineName(gpioConfig.first, *regularGpio);
+        result = configureGpioByLineName(gpioConfig.first, *regularGpio);
         break;
       }
       case (gpio::GpioTypes::CALLBACK): {
@@ -83,8 +84,11 @@ ReturnValue_t LinuxLibgpioIF::configureGpios(GpioMap& mapToAdd) {
                                gpioCallback->initValue, gpioCallback->callbackArgs);
       }
     }
+    if (result != RETURN_OK) {
+      return GPIO_INIT_FAILED;
+    }
   }
-  return RETURN_OK;
+  return result;
 }
 
 ReturnValue_t LinuxLibgpioIF::configureGpioByLabel(gpioId_t gpioId,
diff --git a/hal/src/fsfw_hal/linux/gpio/LinuxLibgpioIF.h b/hal/src/fsfw_hal/linux/gpio/LinuxLibgpioIF.h
index 7d49e6e20..fcc9c7753 100644
--- a/hal/src/fsfw_hal/linux/gpio/LinuxLibgpioIF.h
+++ b/hal/src/fsfw_hal/linux/gpio/LinuxLibgpioIF.h
@@ -29,6 +29,8 @@ class LinuxLibgpioIF : public GpioIF, public SystemObject {
       HasReturnvaluesIF::makeReturnCode(gpioRetvalId, 4);
   static constexpr ReturnValue_t GPIO_DUPLICATE_DETECTED =
       HasReturnvaluesIF::makeReturnCode(gpioRetvalId, 5);
+  static constexpr ReturnValue_t GPIO_INIT_FAILED =
+      HasReturnvaluesIF::makeReturnCode(gpioRetvalId, 6);
 
   LinuxLibgpioIF(object_id_t objectId);
   virtual ~LinuxLibgpioIF();
diff --git a/hal/src/fsfw_hal/linux/spi/SpiCookie.cpp b/hal/src/fsfw_hal/linux/spi/SpiCookie.cpp
index e6271c5ee..c94fcdf1b 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 5aa721381..72c79df65 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/hal/src/fsfw_hal/linux/uart/UartCookie.cpp b/hal/src/fsfw_hal/linux/uart/UartCookie.cpp
index aa2dd2146..3fedc9d44 100644
--- a/hal/src/fsfw_hal/linux/uart/UartCookie.cpp
+++ b/hal/src/fsfw_hal/linux/uart/UartCookie.cpp
@@ -24,9 +24,7 @@ void UartCookie::setParityEven() { parity = Parity::EVEN; }
 
 Parity UartCookie::getParity() const { return parity; }
 
-void UartCookie::setBitsPerWord(BitsPerWord bitsPerWord_) {
-  bitsPerWord = bitsPerWord_;
-}
+void UartCookie::setBitsPerWord(BitsPerWord bitsPerWord_) { bitsPerWord = bitsPerWord_; }
 
 BitsPerWord UartCookie::getBitsPerWord() const { return bitsPerWord; }
 
diff --git a/src/fsfw/cfdp/pdu/HeaderSerializer.h b/src/fsfw/cfdp/pdu/HeaderSerializer.h
index 8f2fc3fdd..1de97d63d 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 c09a421eb..26a739212 100644
--- a/src/fsfw/container/FixedArrayList.h
+++ b/src/fsfw/container/FixedArrayList.h
@@ -9,7 +9,7 @@
  */
 template <typename T, size_t MAX_SIZE, typename count_t = uint8_t>
 class FixedArrayList : public ArrayList<T, count_t> {
-#if !defined(_MSC_VER)
+#if !defined(_MSC_VER) && !defined(__clang__)
   static_assert(MAX_SIZE <= (std::pow(2, sizeof(count_t) * 8) - 1),
                 "count_t is not large enough to hold MAX_SIZE");
 #endif
diff --git a/src/fsfw/container/HybridIterator.h b/src/fsfw/container/HybridIterator.h
index e8b24a3d6..ad000ec25 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 7032f8171..227b859bf 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 1b4bacdad..dc6ec135a 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/LocalDataPoolManager.cpp b/src/fsfw/datapoollocal/LocalDataPoolManager.cpp
index 6053bd438..781d8f71f 100644
--- a/src/fsfw/datapoollocal/LocalDataPoolManager.cpp
+++ b/src/fsfw/datapoollocal/LocalDataPoolManager.cpp
@@ -787,9 +787,9 @@ ReturnValue_t LocalDataPoolManager::generateSetStructurePacket(sid_t sid, bool i
   // Serialize set packet into store.
   size_t size = 0;
   result = setPacket.serialize(&storePtr, &size, expectedSize, SerializeIF::Endianness::BIG);
-  if(result != HasReturnvaluesIF::RETURN_OK) {
-      ipcStore->deleteData(storeId);
-      return result;
+  if (result != HasReturnvaluesIF::RETURN_OK) {
+    ipcStore->deleteData(storeId);
+    return result;
   }
   if (expectedSize != size) {
     printWarningOrError(sif::OutputTypes::OUT_WARNING, "generateSetStructurePacket",
@@ -806,8 +806,8 @@ ReturnValue_t LocalDataPoolManager::generateSetStructurePacket(sid_t sid, bool i
   }
 
   result = hkQueue->reply(&reply);
-  if(result != HasReturnvaluesIF::RETURN_OK) {
-      ipcStore->deleteData(storeId);
+  if (result != HasReturnvaluesIF::RETURN_OK) {
+    ipcStore->deleteData(storeId);
   }
   return result;
 }
diff --git a/src/fsfw/datapoollocal/LocalPoolDataSetBase.cpp b/src/fsfw/datapoollocal/LocalPoolDataSetBase.cpp
index 4a0762126..62fdb184f 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 56e190df1..b2ffa4c18 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 4a9a8aa2e..cefc47406 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.
@@ -1070,11 +1070,11 @@ 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 f7775d45b..ec98e22a7 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 4e1f39222..c5962ab3e 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/ipc/MessageQueueBase.cpp b/src/fsfw/ipc/MessageQueueBase.cpp
index 1b0934ff3..c43670ed5 100644
--- a/src/fsfw/ipc/MessageQueueBase.cpp
+++ b/src/fsfw/ipc/MessageQueueBase.cpp
@@ -1,9 +1,9 @@
 #include "MessageQueueBase.h"
 
-MessageQueueBase::MessageQueueBase(MessageQueueId_t id, MessageQueueId_t defaultDest,
-    MqArgs* args): id(id) {
+MessageQueueBase::MessageQueueBase(MessageQueueId_t id, MessageQueueId_t defaultDest, MqArgs* args)
+    : id(id) {
   this->defaultDest = defaultDest;
-  if(args != nullptr) {
+  if (args != nullptr) {
     this->args = *args;
   }
 }
@@ -23,35 +23,25 @@ ReturnValue_t MessageQueueBase::reply(MessageQueueMessageIF* message) {
 }
 
 ReturnValue_t MessageQueueBase::receiveMessage(MessageQueueMessageIF* message,
-                                           MessageQueueId_t* receivedFrom) {
+                                               MessageQueueId_t* receivedFrom) {
   ReturnValue_t status = this->receiveMessage(message);
   *receivedFrom = this->last;
   return status;
 }
 
-MessageQueueId_t MessageQueueBase::getLastPartner() const {
-  return last;
-}
+MessageQueueId_t MessageQueueBase::getLastPartner() const { return last; }
 
-MessageQueueId_t MessageQueueBase::getId() const {
-  return id;
-}
+MessageQueueId_t MessageQueueBase::getId() const { return id; }
 
-MqArgs& MessageQueueBase::getMqArgs() {
-  return args;
-}
+MqArgs& MessageQueueBase::getMqArgs() { return args; }
 
 void MessageQueueBase::setDefaultDestination(MessageQueueId_t defaultDestination) {
   this->defaultDest = defaultDestination;
 }
 
-MessageQueueId_t MessageQueueBase::getDefaultDestination() const {
-  return defaultDest;
-}
+MessageQueueId_t MessageQueueBase::getDefaultDestination() const { return defaultDest; }
 
-bool MessageQueueBase::isDefaultDestinationSet() const {
-  return (defaultDest != NO_QUEUE);
-}
+bool MessageQueueBase::isDefaultDestinationSet() const { return (defaultDest != NO_QUEUE); }
 
 ReturnValue_t MessageQueueBase::sendMessage(MessageQueueId_t sendTo, MessageQueueMessageIF* message,
                                             bool ignoreFault) {
diff --git a/src/fsfw/ipc/MessageQueueBase.h b/src/fsfw/ipc/MessageQueueBase.h
index 8313f69ac..942b61217 100644
--- a/src/fsfw/ipc/MessageQueueBase.h
+++ b/src/fsfw/ipc/MessageQueueBase.h
@@ -1,11 +1,11 @@
 #ifndef FSFW_SRC_FSFW_IPC_MESSAGEQUEUEBASE_H_
 #define FSFW_SRC_FSFW_IPC_MESSAGEQUEUEBASE_H_
 
-#include <fsfw/ipc/definitions.h>
 #include <fsfw/ipc/MessageQueueIF.h>
+#include <fsfw/ipc/definitions.h>
 
-class MessageQueueBase: public MessageQueueIF {
-public:
+class MessageQueueBase : public MessageQueueIF {
+ public:
   MessageQueueBase(MessageQueueId_t id, MessageQueueId_t defaultDest, MqArgs* mqArgs);
   virtual ~MessageQueueBase();
 
@@ -17,25 +17,24 @@ public:
   virtual MessageQueueId_t getDefaultDestination() const override;
   virtual bool isDefaultDestinationSet() const override;
   virtual ReturnValue_t sendMessage(MessageQueueId_t sendTo, MessageQueueMessageIF* message,
-      bool ignoreFault) override;
+                                    bool ignoreFault) override;
   virtual ReturnValue_t sendToDefault(MessageQueueMessageIF* message) override;
   virtual ReturnValue_t reply(MessageQueueMessageIF* message) override;
   virtual ReturnValue_t receiveMessage(MessageQueueMessageIF* message,
-      MessageQueueId_t* receivedFrom) override;
-  virtual ReturnValue_t sendToDefaultFrom(MessageQueueMessageIF* message,
-      MessageQueueId_t sentFrom, bool ignoreFault = false) override;
+                                       MessageQueueId_t* receivedFrom) override;
+  virtual ReturnValue_t sendToDefaultFrom(MessageQueueMessageIF* message, MessageQueueId_t sentFrom,
+                                          bool ignoreFault = false) override;
 
   // OSAL specific, forward the abstract function
   virtual ReturnValue_t receiveMessage(MessageQueueMessageIF* message) = 0;
   virtual ReturnValue_t sendMessageFrom(MessageQueueId_t sendTo, MessageQueueMessageIF* message,
                                         MessageQueueId_t sentFrom, bool ignoreFault = false) = 0;
-protected:
+
+ protected:
   MessageQueueId_t id = MessageQueueIF::NO_QUEUE;
   MessageQueueId_t last = MessageQueueIF::NO_QUEUE;
   MessageQueueId_t defaultDest = MessageQueueIF::NO_QUEUE;
   MqArgs args = {};
 };
 
-
-
 #endif /* FSFW_SRC_FSFW_IPC_MESSAGEQUEUEBASE_H_ */
diff --git a/src/fsfw/ipc/MessageQueueIF.h b/src/fsfw/ipc/MessageQueueIF.h
index d7b6889b6..9532b2d61 100644
--- a/src/fsfw/ipc/MessageQueueIF.h
+++ b/src/fsfw/ipc/MessageQueueIF.h
@@ -2,6 +2,7 @@
 #define FSFW_IPC_MESSAGEQUEUEIF_H_
 
 #include <fsfw/ipc/definitions.h>
+
 #include <cstdint>
 
 #include "../returnvalues/HasReturnvaluesIF.h"
@@ -45,7 +46,8 @@ class MessageQueueIF {
   virtual ReturnValue_t reply(MessageQueueMessageIF* message) = 0;
 
   /**
-   * @brief	This function reads available messages from the message queue and returns the sender.
+   * @brief	This function reads available messages from the message queue and returns the
+   * sender.
    * @details
    * It works identically to the other receiveMessage call, but in addition
    * returns the sender's queue id.
diff --git a/src/fsfw/monitoring/MonitoringMessageContent.h b/src/fsfw/monitoring/MonitoringMessageContent.h
index 0ac455ebb..fb3ace3da 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 6d5b83035..eeb68b8fb 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/UdpTcPollingTask.cpp b/src/fsfw/osal/common/UdpTcPollingTask.cpp
index ab982a3c8..38fb19211 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 afcd32a1b..894716d70 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 0efe1c744..6089f266a 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 78843ccd3..b0a67430f 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/freertos/MessageQueue.h b/src/fsfw/osal/freertos/MessageQueue.h
index 00dfea680..ee3479aaa 100644
--- a/src/fsfw/osal/freertos/MessageQueue.h
+++ b/src/fsfw/osal/freertos/MessageQueue.h
@@ -2,6 +2,7 @@
 #define FSFW_OSAL_FREERTOS_MESSAGEQUEUE_H_
 
 #include <fsfw/ipc/MessageQueueBase.h>
+
 #include "FreeRTOS.h"
 #include "TaskManagement.h"
 #include "fsfw/internalerror/InternalErrorReporterIF.h"
diff --git a/src/fsfw/osal/host/CMakeLists.txt b/src/fsfw/osal/host/CMakeLists.txt
index 2d29ce5df..8b11a5312 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/host/MessageQueue.h b/src/fsfw/osal/host/MessageQueue.h
index bb4f26a10..4020c6dcc 100644
--- a/src/fsfw/osal/host/MessageQueue.h
+++ b/src/fsfw/osal/host/MessageQueue.h
@@ -1,17 +1,17 @@
 #ifndef FRAMEWORK_OSAL_HOST_MESSAGEQUEUE_H_
 #define FRAMEWORK_OSAL_HOST_MESSAGEQUEUE_H_
 
-#include "fsfw/ipc/MessageQueueBase.h"
+#include <memory>
+#include <queue>
+
 #include "fsfw/internalerror/InternalErrorReporterIF.h"
+#include "fsfw/ipc/MessageQueueBase.h"
 #include "fsfw/ipc/MessageQueueIF.h"
 #include "fsfw/ipc/MessageQueueMessage.h"
 #include "fsfw/ipc/MutexIF.h"
 #include "fsfw/ipc/definitions.h"
 #include "fsfw/timemanager/Clock.h"
 
-#include <memory>
-#include <queue>
-
 /**
  * @brief		This class manages sending and receiving of
  * 				message queue messages.
diff --git a/src/fsfw/osal/linux/CMakeLists.txt b/src/fsfw/osal/linux/CMakeLists.txt
index 679b29319..2e88d6d05 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/osal/linux/MessageQueue.h b/src/fsfw/osal/linux/MessageQueue.h
index 8614d101b..108ec797d 100644
--- a/src/fsfw/osal/linux/MessageQueue.h
+++ b/src/fsfw/osal/linux/MessageQueue.h
@@ -61,8 +61,7 @@ class MessageQueue : public MessageQueueBase {
   ReturnValue_t receiveMessage(MessageQueueMessageIF* message) override;
   ReturnValue_t flush(uint32_t* count) override;
   ReturnValue_t sendMessageFrom(MessageQueueId_t sendTo, MessageQueueMessageIF* message,
-                                        MessageQueueId_t sentFrom,
-                                        bool ignoreFault = false) override;
+                                MessageQueueId_t sentFrom, bool ignoreFault = false) override;
 
  protected:
   /**
diff --git a/src/fsfw/osal/rtems/MessageQueue.h b/src/fsfw/osal/rtems/MessageQueue.h
index 4648fdfa5..bb31a5087 100644
--- a/src/fsfw/osal/rtems/MessageQueue.h
+++ b/src/fsfw/osal/rtems/MessageQueue.h
@@ -2,6 +2,7 @@
 #define FSFW_OSAL_RTEMS_MESSAGEQUEUE_H_
 
 #include <fsfw/ipc/MessageQueueBase.h>
+
 #include "RtemsBasic.h"
 #include "fsfw/internalerror/InternalErrorReporterIF.h"
 #include "fsfw/ipc/MessageQueueIF.h"
@@ -52,8 +53,8 @@ class MessageQueue : public MessageQueueBase {
   // Implement non-generic MessageQueueIF functions not handled by MessageQueueBase
   ReturnValue_t flush(uint32_t* count) override;
   ReturnValue_t sendMessageFrom(MessageQueueId_t sendTo, MessageQueueMessageIF* message,
-                                        MessageQueueId_t sentFrom = NO_QUEUE,
-                                        bool ignoreFault = false) override;
+                                MessageQueueId_t sentFrom = NO_QUEUE,
+                                bool ignoreFault = false) override;
 
  private:
   /**
diff --git a/src/fsfw/osal/rtems/PeriodicTask.h b/src/fsfw/osal/rtems/PeriodicTask.h
index 24ce4af1e..9f47dfc61 100644
--- a/src/fsfw/osal/rtems/PeriodicTask.h
+++ b/src/fsfw/osal/rtems/PeriodicTask.h
@@ -59,14 +59,13 @@ class PeriodicTask : public RTEMSTaskBase, public PeriodicTaskIF {
    */
   ReturnValue_t addComponent(object_id_t object) override;
 
-/**
+  /**
    * Adds an object to the list of objects to be executed.
    * The objects are executed in the order added.
    * @param object pointer to the object to add.
    * @return RETURN_OK on success, RETURN_FAILED if the object could not be added.
    */
-  ReturnValue_t addComponent(ExecutableObjectIF* object) override;
-
+  ReturnValue_t addComponent(ExecutableObjectIF *object) override;
 
   uint32_t getPeriodMs() const override;
 
diff --git a/src/fsfw/power/Fuse.h b/src/fsfw/power/Fuse.h
index e6f9c1492..787fa38d6 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/Service3Housekeeping.h b/src/fsfw/pus/Service3Housekeeping.h
index c1928891e..70f157625 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 a837bf83e..ab8c1b168 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];
diff --git a/src/fsfw/subsystem/Subsystem.h b/src/fsfw/subsystem/Subsystem.h
index 2c78c8cd3..f1e7228d0 100644
--- a/src/fsfw/subsystem/Subsystem.h
+++ b/src/fsfw/subsystem/Subsystem.h
@@ -1,14 +1,13 @@
 #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"
 
 /**
@@ -127,18 +126,18 @@ 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 8cfd5be07..52f9891e0 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 9ebd1d790..1f84dd03d 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 19c980d09..2a2316af8 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 c8ebbd978..16d968fb9 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 0ae195051..867fc2874 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
diff --git a/tests/src/fsfw_tests/unit/mocks/MessageQueueMockBase.h b/tests/src/fsfw_tests/unit/mocks/MessageQueueMockBase.h
index c3d08a86e..4236593ef 100644
--- a/tests/src/fsfw_tests/unit/mocks/MessageQueueMockBase.h
+++ b/tests/src/fsfw_tests/unit/mocks/MessageQueueMockBase.h
@@ -4,8 +4,8 @@
 #include <cstring>
 #include <queue>
 
-#include "fsfw/ipc/MessageQueueBase.h"
 #include "fsfw/ipc/CommandMessage.h"
+#include "fsfw/ipc/MessageQueueBase.h"
 #include "fsfw/ipc/MessageQueueIF.h"
 #include "fsfw/ipc/MessageQueueMessage.h"
 #include "fsfw_tests/unit/CatchDefinitions.h"
@@ -13,7 +13,7 @@
 class MessageQueueMockBase : public MessageQueueBase {
  public:
   MessageQueueMockBase()
-   : MessageQueueBase(MessageQueueIF::NO_QUEUE, MessageQueueIF::NO_QUEUE, nullptr) {}
+      : MessageQueueBase(MessageQueueIF::NO_QUEUE, MessageQueueIF::NO_QUEUE, nullptr) {}
 
   uint8_t messageSentCounter = 0;
   bool messageSent = false;
diff --git a/tests/src/fsfw_tests/unit/timemanager/TestCCSDSTime.cpp b/tests/src/fsfw_tests/unit/timemanager/TestCCSDSTime.cpp
index a43ff8ab0..e96ddfc91 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;