diff --git a/src/Mod/Cloud/App/AppCloud.cpp b/src/Mod/Cloud/App/AppCloud.cpp
index 87f9c24779..5703e84427 100644
--- a/src/Mod/Cloud/App/AppCloud.cpp
+++ b/src/Mod/Cloud/App/AppCloud.cpp
@@ -259,9 +259,9 @@ void Cloud::CloudWriter::createBucket()
         eraseSubStr(strURL,"https://");
 
         if ( this->ProtocolVersion ==  "2" )
-                RequestData = Cloud::ComputeDigestAmzS3v2("PUT", "application/xml", path, this->TokenSecret, NULL, 0);
+                RequestData = Cloud::ComputeDigestAmzS3v2("PUT", "application/xml", path, this->TokenSecret, nullptr, 0);
         else
-                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("PUT", strURL.c_str(), "application/xml", path, this->TokenSecret, NULL, 0, NULL, this->Region);
+                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("PUT", strURL.c_str(), "application/xml", path, this->TokenSecret, nullptr, 0, nullptr, this->Region);
 
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
@@ -273,7 +273,7 @@ void Cloud::CloudWriter::createBucket()
 
         if ( curl )
         {
-                struct curl_slist *chunk = NULL;
+                struct curl_slist *chunk = nullptr;
                 char URL[256];
                 // Let's build our own header
                 std::string strURL(this->URL);
@@ -303,7 +303,7 @@ void Cloud::CloudWriter::createBucket()
                 // curl read a file not a memory buffer (it shall be able to do it)
                 curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);
 
-                curl_buffer.ptr = NULL;
+                curl_buffer.ptr = nullptr;
                 curl_buffer.remaining_size = (size_t) 0;
 
                 curl_easy_setopt(curl, CURLOPT_READDATA, &curl_buffer);
@@ -355,12 +355,12 @@ struct Cloud::AmzDatav4 *Cloud::ComputeDigestAmzS3v4(char *operation, const char
 #else
         struct timeval tv;
         setenv("TZ","GMT",1);
-        gettimeofday(&tv, NULL);
+        gettimeofday(&tv, nullptr);
         tm = localtime(&tv.tv_sec);
 #endif
         strftime(returnData->dateFormattedD,256,"%Y%m%d", tm);
         strftime(returnData->dateFormattedS,256,"%Y%m%dT%H%M%SZ", tm);
-        returnData->MD5=NULL;
+        returnData->MD5=nullptr;
 
 // We must evaluate the canonical request
         canonical_request=(char *) malloc(4096*(sizeof(char*)));
@@ -368,7 +368,7 @@ struct Cloud::AmzDatav4 *Cloud::ComputeDigestAmzS3v4(char *operation, const char
         strcat(canonical_request,"\n");
         strcat(canonical_request,target);
         strcat(canonical_request,"\n");
-        if ( parameters == NULL )
+        if ( parameters == nullptr )
                 strcat(canonical_request,"\n");
         else
         {
@@ -383,10 +383,10 @@ struct Cloud::AmzDatav4 *Cloud::ComputeDigestAmzS3v4(char *operation, const char
         strcat(canonical_request, "\n\n");
         strcat(canonical_request, "host;x-amz-date\n");
         // We must add there the file SHA256 Hash        
-        returnData->SHA256Sum=NULL;
+        returnData->SHA256Sum=nullptr;
         if ( strcmp(operation,"PUT") == 0 )
         {
-                if (  ptr != NULL )
+                if (  ptr != nullptr )
                 {
                         returnData->SHA256Sum=Cloud::SHA256Sum(ptr,size);
                         strcat(canonical_request, returnData->SHA256Sum);
@@ -432,30 +432,30 @@ struct Cloud::AmzDatav4 *Cloud::ComputeDigestAmzS3v4(char *operation, const char
         std::string temporary;
 
         kDate = HMAC(EVP_sha256(),kSecret,strlen(kSecret),
-                (const unsigned char *)returnData->dateFormattedD,strlen(returnData->dateFormattedD),NULL,&HMACLength);
+                (const unsigned char *)returnData->dateFormattedD,strlen(returnData->dateFormattedD),nullptr,&HMACLength);
 
         temporary = getHexValue(kDate,HMACLength);
         temporary = getHexValue(kDate,HMACLength);
 
         // We can now compute the remaining parts
         kRegion = HMAC(EVP_sha256(),kDate,HMACLength,
-                (const unsigned char *)Region.c_str(),strlen(Region.c_str()),NULL,&HMACLength);
+                (const unsigned char *)Region.c_str(),strlen(Region.c_str()),nullptr,&HMACLength);
 
         temporary = getHexValue(kRegion,HMACLength);
 
         kService = HMAC(EVP_sha256(),kRegion,HMACLength,
-                (const unsigned char *)"s3",strlen("s3"),NULL,&HMACLength);
+                (const unsigned char *)"s3",strlen("s3"),nullptr,&HMACLength);
 
         temporary = getHexValue(kService,HMACLength);
 
         kSigning = HMAC(EVP_sha256(),kService,HMACLength,
-                (const unsigned char *)"aws4_request",strlen("aws4_request"),NULL,&HMACLength);
+                (const unsigned char *)"aws4_request",strlen("aws4_request"),nullptr,&HMACLength);
 
         temporary = getHexValue(kService,HMACLength);
 
 
         kSigned = HMAC(EVP_sha256(),kSigning,HMACLength,
-                (const unsigned char *)stringToSign,strlen(stringToSign),NULL,&HMACLength);
+                (const unsigned char *)stringToSign,strlen(stringToSign),nullptr,&HMACLength);
 
         temporary = getHexValue(kSigned,HMACLength);
 
@@ -503,14 +503,14 @@ struct Cloud::AmzData *Cloud::ComputeDigestAmzS3v2(char *operation, char *data_t
 #else
         struct timeval tv;
         setenv("TZ","GMT",1);
-        gettimeofday(&tv, NULL);
+        gettimeofday(&tv, nullptr);
         tm = localtime(&tv.tv_sec);
 #endif
         strftime(date_formatted,256,"%a, %d %b %Y %T %z", tm);
-        returnData->MD5=NULL;
+        returnData->MD5=nullptr;
         if ( strcmp(operation,"PUT") == 0 )
         {
-                if (  ptr != NULL )
+                if (  ptr != nullptr )
                 {
                         returnData->MD5=Cloud::MD5Sum(ptr,size);
                         sprintf(StringToSign,"%s\n%s\n%s\n%s\n%s", operation, returnData->MD5, data_type, date_formatted, target);
@@ -522,7 +522,7 @@ struct Cloud::AmzData *Cloud::ComputeDigestAmzS3v2(char *operation, char *data_t
                 sprintf(StringToSign,"%s\n\n%s\n%s\n%s", operation, data_type, date_formatted, target);
         // We have to use HMAC encoding and SHA1
         digest=HMAC(EVP_sha1(),Secret,strlen(Secret),
-                (const unsigned char *)&StringToSign,strlen(StringToSign),NULL,&HMACLength);
+                (const unsigned char *)&StringToSign,strlen(StringToSign),nullptr,&HMACLength);
         returnData->digest = Base::base64_encode(digest,HMACLength);
         strcpy(returnData->dateFormatted,date_formatted);
         return returnData;
@@ -559,7 +559,7 @@ char *Cloud::MD5Sum(const char *ptr, long size)
 struct curl_slist *Cloud::BuildHeaderAmzS3v4(const char *URL, const char *PublicKey, struct Cloud::AmzDatav4 *Data)
 {
         char header_data[1024];
-        struct curl_slist *chunk = NULL;
+        struct curl_slist *chunk = nullptr;
 
         // Build the Host: entry
         // sprintf(header_data,"Host: %s:%s", URL, TCPPort);
@@ -578,7 +578,7 @@ struct curl_slist *Cloud::BuildHeaderAmzS3v4(const char *URL, const char *Public
 
         // If ptr is not null we must compute the MD5-Sum as to validate later the ETag
         // and add the MD5-Content: entry to the header
-        if ( Data->MD5 != NULL )
+        if ( Data->MD5 != nullptr )
         {
                 sprintf(header_data,"Content-MD5: %s", Data->MD5);
                 chunk = curl_slist_append(chunk, header_data);
@@ -586,7 +586,7 @@ struct curl_slist *Cloud::BuildHeaderAmzS3v4(const char *URL, const char *Public
                 free((void *)Data->MD5);
         }
 
-        if ( Data->SHA256Sum != NULL ) 
+        if ( Data->SHA256Sum != nullptr ) 
         {
                 sprintf(header_data,"x-amz-content-sha256: %s", Data->SHA256Sum);
                 chunk = curl_slist_append(chunk, header_data);
@@ -609,7 +609,7 @@ struct curl_slist *Cloud::BuildHeaderAmzS3v4(const char *URL, const char *Public
 struct curl_slist *Cloud::BuildHeaderAmzS3v2(const char *URL, const char *TCPPort, const char *PublicKey, struct Cloud::AmzData *Data)
 {
         char header_data[1024];
-        struct curl_slist *chunk = NULL;
+        struct curl_slist *chunk = nullptr;
 
         // Build the Host: entry
 
@@ -626,7 +626,7 @@ struct curl_slist *Cloud::BuildHeaderAmzS3v2(const char *URL, const char *TCPPor
 
         // If ptr is not null we must compute the MD5-Sum as to validate later the ETag
         // and add the MD5-Content: entry to the header
-        if ( Data->MD5 != NULL )
+        if ( Data->MD5 != nullptr )
         {
                 sprintf(header_data,"Content-MD5: %s", Data->MD5);
                 chunk = curl_slist_append(chunk, header_data);
@@ -669,9 +669,9 @@ Cloud::CloudWriter::CloudWriter(const char* URL, const char* TokenAuth, const ch
         eraseSubStr(strURL,"http://");
         eraseSubStr(strURL,"https://");
         if ( this->ProtocolVersion == "2" )
-                RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/xml", path, this->TokenSecret, NULL, 0);
+                RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/xml", path, this->TokenSecret, nullptr, 0);
         else
-                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("GET", strURL.c_str(), "application/xml", path, this->TokenSecret, NULL, 0, NULL, this->Region);
+                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("GET", strURL.c_str(), "application/xml", path, this->TokenSecret, nullptr, 0, nullptr, this->Region);
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
         curl = curl_easy_init();
@@ -682,7 +682,7 @@ Cloud::CloudWriter::CloudWriter(const char* URL, const char* TokenAuth, const ch
         if ( curl )
         {
                 // Let's build our own header
-                struct curl_slist *chunk = NULL;
+                struct curl_slist *chunk = nullptr;
                 char URL[256];
                 std::string strURL(this->URL);
                 eraseSubStr(strURL,"http://");
@@ -850,7 +850,7 @@ Cloud::CloudReader::CloudReader(const char* URL, const char* TokenAuth, const ch
         CURL *curl;
         CURLcode res;
         bool GetBucketContentList=true;
-        struct curl_slist *chunk = NULL;
+        struct curl_slist *chunk = nullptr;
         char parameters[1024];
 
 
@@ -903,13 +903,13 @@ Cloud::CloudReader::CloudReader(const char* URL, const char* TokenAuth, const ch
 
                         if ( this->ProtocolVersion == "2" )
                         {
-                                RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/xml", path, this->TokenSecret, NULL, 0);
+                                RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/xml", path, this->TokenSecret, nullptr, 0);
                                 chunk = Cloud::BuildHeaderAmzS3v2(strURL.c_str(), this->TCPPort, this->TokenAuth, RequestData);
                                 delete RequestData;
                         }
                         else
                         {
-                                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("GET", strURL.c_str(),"application/xml", path, this->TokenSecret, NULL, 0, (char *)&parameters[0], this->Region);
+                                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("GET", strURL.c_str(),"application/xml", path, this->TokenSecret, nullptr, 0, (char *)&parameters[0], this->Region);
                                 chunk = Cloud::BuildHeaderAmzS3v4( strURL.c_str(), this->TokenAuth, RequestDatav4);
                                 delete RequestDatav4;
                         }
@@ -979,9 +979,9 @@ void Cloud::CloudReader::DownloadFile(Cloud::CloudReader::FileEntry *entry)
         eraseSubStr(strURL,"http://");
         eraseSubStr(strURL,"https://");
         if ( this->ProtocolVersion == "2" )
-                RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/octet-stream", path, this->TokenSecret, NULL, 0);
+                RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/octet-stream", path, this->TokenSecret, nullptr, 0);
         else
-                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("GET", strURL.c_str(), "application/octet-stream", path, this->TokenSecret, NULL, 0, NULL, this->Region);
+                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("GET", strURL.c_str(), "application/octet-stream", path, this->TokenSecret, nullptr, 0, nullptr, this->Region);
 
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
@@ -992,7 +992,7 @@ void Cloud::CloudReader::DownloadFile(Cloud::CloudReader::FileEntry *entry)
 #endif
         if ( curl )
         {
-                struct curl_slist *chunk = NULL;
+                struct curl_slist *chunk = nullptr;
                 char URL[256];
                 // Let's build our own header
                 std::string strURL(this->URL);
@@ -1031,7 +1031,7 @@ void Cloud::CloudReader::DownloadFile(Cloud::CloudReader::FileEntry *entry)
 
 struct Cloud::CloudReader::FileEntry * Cloud::CloudReader::GetEntry(std::string FileName)
 {
-        struct Cloud::CloudReader::FileEntry *current_entry=NULL;
+        struct Cloud::CloudReader::FileEntry *current_entry=nullptr;
         list<FileEntry*>::const_iterator it1;
 
         for(it1 = FileList.begin(); it1 != FileList.end(); ++it1) {
@@ -1042,7 +1042,7 @@ struct Cloud::CloudReader::FileEntry * Cloud::CloudReader::GetEntry(std::string
                 }
         }
 
-        if ( current_entry != NULL )
+        if ( current_entry != nullptr )
         {
                 (*it1)->touch=1;
                 DownloadFile(*it1);
@@ -1109,7 +1109,7 @@ void Cloud::CloudWriter::pushCloud(const char *FileName, const char *data, long
         if ( this->ProtocolVersion == "2" )
                 RequestData = Cloud::ComputeDigestAmzS3v2("PUT", "application/octet-stream", path, this->TokenSecret, data, size);
         else
-                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("PUT", strURL.c_str(), "application/octet-stream", path, this->TokenSecret, data, size, NULL, this->Region);
+                RequestDatav4 = Cloud::ComputeDigestAmzS3v4("PUT", strURL.c_str(), "application/octet-stream", path, this->TokenSecret, data, size, nullptr, this->Region);
 
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
@@ -1120,7 +1120,7 @@ void Cloud::CloudWriter::pushCloud(const char *FileName, const char *data, long
 #endif
         if ( curl )
         {
-                struct curl_slist *chunk = NULL;
+                struct curl_slist *chunk = nullptr;
                 char URL[256];
                 // Let's build our own header
                 std::string strURL(this->URL);
diff --git a/src/Mod/Cloud/Gui/AppCloudGui.cpp b/src/Mod/Cloud/Gui/AppCloudGui.cpp
index a1064b04f0..703cf99169 100644
--- a/src/Mod/Cloud/Gui/AppCloudGui.cpp
+++ b/src/Mod/Cloud/Gui/AppCloudGui.cpp
@@ -61,7 +61,7 @@ PyMOD_INIT_FUNC(CloudGui)
 {
     if (!Gui::Application::Instance) {
         PyErr_SetString(PyExc_ImportError, "Cannot load Gui module in console application.");
-        PyMOD_Return(0);
+        PyMOD_Return(nullptr);
     }
 
     // instantiating the commands