diff --git a/assignment-client/src/avatars/ScriptableAvatar.cpp b/assignment-client/src/avatars/ScriptableAvatar.cpp
index 044ab86942..383f583327 100644
--- a/assignment-client/src/avatars/ScriptableAvatar.cpp
+++ b/assignment-client/src/avatars/ScriptableAvatar.cpp
@@ -144,10 +144,10 @@ void ScriptableAvatar::update(float deltatime) {
             }
             _animationDetails.currentFrame = currentFrame;
 
-            const QVector<HFMJoint>& modelJoints = _bind->getHFMModel().joints;
+            const std::vector<HFMJoint>& modelJoints = _bind->getHFMModel().joints;
             QStringList animationJointNames = _animation->getJointNames();
 
-            const int nJoints = modelJoints.size();
+            const auto nJoints = (int)modelJoints.size();
             if (_jointData.size() != nJoints) {
                 _jointData.resize(nJoints);
             }
diff --git a/libraries/fbx/src/GLTFSerializer.cpp b/libraries/fbx/src/GLTFSerializer.cpp
index 4c4050c935..4f1d871158 100755
--- a/libraries/fbx/src/GLTFSerializer.cpp
+++ b/libraries/fbx/src/GLTFSerializer.cpp
@@ -1613,7 +1613,7 @@ bool GLTFSerializer::buildGeometry(HFMModel& hfmModel, const hifi::VariantHash&
             hfmModel.meshExtents.minimum -= glm::vec3(EPSILON, EPSILON, EPSILON);
             hfmModel.meshExtents.maximum += glm::vec3(EPSILON, EPSILON, EPSILON);
            
-            mesh.meshIndex = hfmModel.meshes.size();
+            mesh.meshIndex = (int)hfmModel.meshes.size();
         }
         ++nodecount;
     }
diff --git a/tools/vhacd-util/src/VHACDUtil.cpp b/tools/vhacd-util/src/VHACDUtil.cpp
index a5ad5bc891..3410d35e6a 100644
--- a/tools/vhacd-util/src/VHACDUtil.cpp
+++ b/tools/vhacd-util/src/VHACDUtil.cpp
@@ -154,7 +154,7 @@ void vhacd::VHACDUtil::fattenMesh(const HFMMesh& mesh, const glm::mat4& modelOff
         newMeshPart.triangleIndices << index0 << index3 << index1;
         newMeshPart.triangleIndices << index1 << index3 << index2;
         newMeshPart.triangleIndices << index2 << index3 << index0;
-        result.parts.append(newMeshPart);
+        result.parts.push_back(newMeshPart);
     }
 }
 
@@ -259,8 +259,8 @@ void vhacd::VHACDUtil::getConvexResults(VHACD::IVHACD* convexifier, HFMMesh& res
         VHACD::IVHACD::ConvexHull hull;
         convexifier->GetConvexHull(j, hull);
 
-        resultMesh.parts.append(HFMMeshPart());
-        HFMMeshPart& resultMeshPart = resultMesh.parts.last();
+        resultMesh.parts.push_back(HFMMeshPart());
+        HFMMeshPart& resultMeshPart = resultMesh.parts.back();
 
         int hullIndexStart = resultMesh.vertices.size();
         resultMesh.vertices.reserve(hullIndexStart + hull.m_nPoints);
@@ -300,8 +300,8 @@ bool vhacd::VHACDUtil::computeVHACD(HFMModel& hfmModel,
     }
 
     // count the mesh-parts
-    int numParts = 0;
-    foreach (const HFMMesh& mesh, hfmModel.meshes) {
+    size_t numParts = 0;
+    for (const HFMMesh& mesh : hfmModel.meshes) {
         numParts += mesh.parts.size();
     }
     if (_verbose) {
@@ -311,8 +311,8 @@ bool vhacd::VHACDUtil::computeVHACD(HFMModel& hfmModel,
     VHACD::IVHACD * convexifier = VHACD::CreateVHACD();
 
     result.meshExtents.reset();
-    result.meshes.append(HFMMesh());
-    HFMMesh &resultMesh = result.meshes.last();
+    result.meshes.push_back(HFMMesh());
+    HFMMesh &resultMesh = result.meshes.back();
 
     const uint32_t POINT_STRIDE = 3;
     const uint32_t TRIANGLE_STRIDE = 3;
diff --git a/tools/vhacd-util/src/VHACDUtilApp.cpp b/tools/vhacd-util/src/VHACDUtilApp.cpp
index 3d675f8baf..61a6b38181 100644
--- a/tools/vhacd-util/src/VHACDUtilApp.cpp
+++ b/tools/vhacd-util/src/VHACDUtilApp.cpp
@@ -387,7 +387,7 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
         }
 
         if (verbose) {
-            int totalHulls = result.meshes[0].parts.size();
+            auto totalHulls = result.meshes[0].parts.size();
             qDebug() << "output file =" << outputFilename;
             qDebug() << "vertices =" << totalVertices;
             qDebug() << "triangles =" << totalTriangles;
@@ -402,7 +402,7 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
         HFMMesh result;
 
         // count the mesh-parts
-        unsigned int meshCount = 0;
+        size_t meshCount = 0;
         foreach (const HFMMesh& mesh, fbx.meshes) {
             meshCount += mesh.parts.size();
         }
@@ -412,7 +412,7 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
             vUtil.fattenMesh(mesh, fbx.offset, result);
         }
 
-        newFbx.meshes.append(result);
+        newFbx.meshes.push_back(result);
         writeOBJ(outputFilename, newFbx, outputCentimeters);
     }
 }