diff --git a/readme-qt.md b/readme-qt.md
index 87c4510..406be50 100644
--- a/readme-qt.md
+++ b/readme-qt.md
@@ -1,5 +1,22 @@
+Official online installer
+-------------------------
+
 [qt.io/download](https://www.qt.io/download)
 
 * Downloads for open source users
 * Go open source
 * Download the Qt Online Installer
+
+
+
+macOS note (desktop)
+--------------------
+
+It's trivial to install Qt5.15/desktop with **brew**:
+```
+brew install qt@5
+```
+Just create an alias for **qmake**, like:
+```
+alias qmake='/usr/local/Cellar/qt@5/5.15.8_3/bin/qmake'
+```
diff --git a/readme.md b/readme.md
index 3c79c69..3300ffe 100644
--- a/readme.md
+++ b/readme.md
@@ -47,7 +47,8 @@ Qt Creator.
 TODO
 ----
 
-* port to CMake
+* add (very simple) meshtastic app example
+* port to CMake?
 
 
 macOS note
diff --git a/src/cpp/ecl_ext.cpp b/src/cpp/ecl_ext.cpp
index d9b7404..659859a 100644
--- a/src/cpp/ecl_ext.cpp
+++ b/src/cpp/ecl_ext.cpp
@@ -291,7 +291,7 @@ cl_object qload_cpp(cl_object l_lib_name, cl_object l_unload) { /// qload-c++
       }
       return ECL_NIL;
     }
-    if (!lib) {
+    if (lib == nullptr) {
       lib = new QLibrary(libName);
       libraries[libName] = lib;
     }
diff --git a/src/cpp/ecl_fun_plugin.h b/src/cpp/ecl_fun_plugin.h
index d5b95e3..660b4d3 100644
--- a/src/cpp/ecl_fun_plugin.h
+++ b/src/cpp/ecl_fun_plugin.h
@@ -463,7 +463,7 @@ QVariant ecl_fun(const QByteArray& pkgFun,
   // 'ecl_fun("cl:format", ...);' to prevent useless error messages from ECL
   // like "the function NIL is undefined"
   void* symbol = lisp_functions.value(pkgFun);
-  if (!symbol) {
+  if (symbol == nullptr) {
     int p = pkgFun.indexOf(':');
     QByteArray pkg = (p == -1) ? "qml-user" : pkgFun.left(p);
     QByteArray fun = pkgFun.mid(pkgFun.lastIndexOf(':') + 1);
diff --git a/src/cpp/qt_ecl.cpp b/src/cpp/qt_ecl.cpp
index 116d48e..06e43b1 100644
--- a/src/cpp/qt_ecl.cpp
+++ b/src/cpp/qt_ecl.cpp
@@ -41,7 +41,7 @@ QVariant ecl_fun(const QByteArray& pkgFun,
                  const QVariant& a15,
                  const QVariant& a16) {
   void* symbol = lisp_functions.value(pkgFun);
-  if (!symbol) {
+  if (symbol == nullptr) {
     int p = pkgFun.indexOf(':');
     QByteArray pkg = (p == -1) ? "qml-user" : pkgFun.left(p);
     QByteArray fun = pkgFun.mid(pkgFun.lastIndexOf(':') + 1);