diff --git a/arangod/Aql/AqlValue.cpp b/arangod/Aql/AqlValue.cpp
index aa0f72503e..e861839961 100644
--- a/arangod/Aql/AqlValue.cpp
+++ b/arangod/Aql/AqlValue.cpp
@@ -34,6 +34,7 @@
 #include <velocypack/Slice.h>
 #include <velocypack/velocypack-aliases.h>
 
+using namespace arangodb;
 using namespace arangodb::aql;
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/arangod/Aql/Condition.cpp b/arangod/Aql/Condition.cpp
index e33ab1b6d9..e46b963686 100644
--- a/arangod/Aql/Condition.cpp
+++ b/arangod/Aql/Condition.cpp
@@ -30,6 +30,7 @@
 #include "Basics/Exceptions.h"
 #include "Basics/json.h"
 #include "Basics/JsonHelper.h"
+#include "Utils/Transaction.h"
 
 #ifdef _WIN32
 // turn off warnings about too long type name for debug symbols blabla in MSVC
@@ -37,6 +38,7 @@
 #pragma warning(disable : 4503)
 #endif
 
+using namespace arangodb;
 using namespace arangodb::aql;
 using CompareResult = ConditionPartCompareResult;
 
@@ -362,7 +364,7 @@ void Condition::andCombine(AstNode const* node) {
 
 std::pair<bool, bool> Condition::findIndexes(
     EnumerateCollectionNode const* node,
-    std::vector<Transaction::IndexHandle>& usedIndexes,
+    std::vector<arangodb::Transaction::IndexHandle>& usedIndexes,
     SortCondition const* sortCondition) {
   TRI_ASSERT(usedIndexes.empty());
   Variable const* reference = node->outVariable();
diff --git a/arangod/Aql/Functions.cpp b/arangod/Aql/Functions.cpp
index cd5e1f08fc..165c7eb9d3 100644
--- a/arangod/Aql/Functions.cpp
+++ b/arangod/Aql/Functions.cpp
@@ -677,7 +677,7 @@ static void GetDocumentByIdentifier(arangodb::AqlTransaction* trx,
     try {
       TRI_voc_cid_t cid;
       RegisterCollectionInTransaction(trx, collectionName, cid);
-    } catch (arangodb::basics::Exception const& ex) {
+    } catch (arangodb::basics::Exception const&) {
       if (ignoreError) {
         return;
       }
@@ -693,7 +693,7 @@ static void GetDocumentByIdentifier(arangodb::AqlTransaction* trx,
       try {
         TRI_voc_cid_t cid;
         RegisterCollectionInTransaction(trx, parts[0], cid);
-      } catch (arangodb::basics::Exception const& ex) {
+      } catch (arangodb::basics::Exception const&) {
         if (ignoreError) {
           return;
         }
@@ -714,7 +714,7 @@ static void GetDocumentByIdentifier(arangodb::AqlTransaction* trx,
       try {
         TRI_voc_cid_t cid;
         RegisterCollectionInTransaction(trx, collectionName, cid);
-      } catch (arangodb::basics::Exception const& ex) {
+      } catch (arangodb::basics::Exception const&) {
         if (ignoreError) {
           return;
         }
diff --git a/arangod/Aql/IndexNode.cpp b/arangod/Aql/IndexNode.cpp
index f9d5a039c1..89786ea050 100644
--- a/arangod/Aql/IndexNode.cpp
+++ b/arangod/Aql/IndexNode.cpp
@@ -28,6 +28,7 @@
 #include "Aql/ExecutionPlan.h"
 #include "Utils/Transaction.h"
 
+using namespace arangodb;
 using namespace arangodb::aql;
 
 using JsonHelper = arangodb::basics::JsonHelper;
@@ -38,7 +39,7 @@ using JsonHelper = arangodb::basics::JsonHelper;
 
 IndexNode::IndexNode(ExecutionPlan* plan, size_t id, TRI_vocbase_t* vocbase,
             Collection const* collection, Variable const* outVariable,
-            std::vector<Transaction::IndexHandle> const& indexes,
+            std::vector<arangodb::Transaction::IndexHandle> const& indexes,
             Condition* condition, bool reverse)
       : ExecutionNode(plan, id),
         _vocbase(vocbase),
diff --git a/arangod/Cluster/ClusterTraverser.cpp b/arangod/Cluster/ClusterTraverser.cpp
index 31673c698b..c15927f8c6 100644
--- a/arangod/Cluster/ClusterTraverser.cpp
+++ b/arangod/Cluster/ClusterTraverser.cpp
@@ -24,6 +24,8 @@
 #include "ClusterTraverser.h"
 #include "Cluster/ClusterMethods.h"
 
+using namespace arangodb;
+
 using ClusterTraversalPath = arangodb::traverser::ClusterTraversalPath;
 using ClusterTraverser = arangodb::traverser::ClusterTraverser;
 
diff --git a/arangod/Utils/Transaction.cpp b/arangod/Utils/Transaction.cpp
index 913d9078cf..43e8997795 100644
--- a/arangod/Utils/Transaction.cpp
+++ b/arangod/Utils/Transaction.cpp
@@ -105,7 +105,7 @@ static bool indexSupportsSort(Index const* idx, arangodb::aql::Variable const* r
 static OperationResult DBServerResponseBad(std::shared_ptr<VPackBuilder> resultBody) {
   VPackSlice res = resultBody->slice();
   return OperationResult(
-      arangodb::basics::VelocyPackHelper::getNumericValue<uint64_t>(
+      arangodb::basics::VelocyPackHelper::getNumericValue<int>(
           res, "errorNum", TRI_ERROR_INTERNAL),
       arangodb::basics::VelocyPackHelper::getStringValue(
           res, "errorMessage", "JSON sent to DBserver was bad"));
diff --git a/arangosh/Benchmark/BenchFeature.cpp b/arangosh/Benchmark/BenchFeature.cpp
index 27561807af..e9eed87f7b 100644
--- a/arangosh/Benchmark/BenchFeature.cpp
+++ b/arangosh/Benchmark/BenchFeature.cpp
@@ -207,7 +207,7 @@ void BenchFeature::start() {
 
     BenchmarkThread* thread = new BenchmarkThread(
         benchmark.get(), &startCondition, &BenchFeature::updateStartCounter,
-        i, (unsigned long)_batchSize, &operationsCounter, client, _keepAlive,
+        static_cast<int>(i), (unsigned long)_batchSize, &operationsCounter, client, _keepAlive,
         _async, _verbose);
 
     threads.push_back(thread);
diff --git a/arangosh/Shell/ShellFeature.cpp b/arangosh/Shell/ShellFeature.cpp
index 5c1ab161ba..abad374b0c 100644
--- a/arangosh/Shell/ShellFeature.cpp
+++ b/arangosh/Shell/ShellFeature.cpp
@@ -147,7 +147,7 @@ void ShellFeature::start() {
   try {
     switch (_runMode) {
       case RunMode::INTERACTIVE:
-        ok = shell->runShell(_positionals);
+        ok = (shell->runShell(_positionals) == TRI_ERROR_NO_ERROR);
         break;
 
       case RunMode::EXECUTE_SCRIPT:
diff --git a/lib/SimpleHttpClient/GeneralClientConnection.cpp b/lib/SimpleHttpClient/GeneralClientConnection.cpp
index 1696f23e84..94b617f6e8 100644
--- a/lib/SimpleHttpClient/GeneralClientConnection.cpp
+++ b/lib/SimpleHttpClient/GeneralClientConnection.cpp
@@ -88,7 +88,7 @@ GeneralClientConnection* GeneralClientConnection::factory(
 
 GeneralClientConnection* GeneralClientConnection::factory(
     std::unique_ptr<Endpoint>& endpoint, double requestTimeout, double connectTimeout,
-    size_t numRetries, uint32_t sslProtocol) {
+    size_t numRetries, uint64_t sslProtocol) {
   if (endpoint->encryption() == Endpoint::EncryptionType::NONE) {
     return new ClientConnection(endpoint, requestTimeout, connectTimeout,
                                 numRetries);
diff --git a/lib/SimpleHttpClient/GeneralClientConnection.h b/lib/SimpleHttpClient/GeneralClientConnection.h
index 680c5a05d1..a8247a30e2 100644
--- a/lib/SimpleHttpClient/GeneralClientConnection.h
+++ b/lib/SimpleHttpClient/GeneralClientConnection.h
@@ -75,7 +75,7 @@ class GeneralClientConnection {
 
   static GeneralClientConnection* factory(
       std::unique_ptr<Endpoint>&, double, double, size_t,
-      uint32_t);
+      uint64_t);
 
   //////////////////////////////////////////////////////////////////////////////
   /// @brief return the endpoint