diff --git a/src/pyastub/pya.cc b/src/pyastub/pya.cc
index 7ec5bdbb4..c343b094d 100644
--- a/src/pyastub/pya.cc
+++ b/src/pyastub/pya.cc
@@ -31,14 +31,23 @@ static void fail (const char *file, int line)
   throw tl::ScriptError (tl::to_string (QObject::tr ("Python support not compiled in")).c_str (), file, line, "missing_feature", std::vector<tl::BacktraceElement> ());
 }
 
-PythonInterpreter::PythonInterpreter () 
-{ 
-  // .. nothing ..
+static PythonInterpreter *sp_pya_interpreter = 0;
+
+PythonInterpreter::PythonInterpreter ()
+{
+  tl_assert (! sp_pya_interpreter);
+  sp_pya_interpreter = this;
 }
 
-PythonInterpreter::~PythonInterpreter () 
+PythonInterpreter::~PythonInterpreter ()
 {
-  // .. nothing ..
+  //  This prevents reinitialization
+  sp_pya_interpreter = reinterpret_cast<PythonInterpreter *> (1);
+}
+
+PythonInterpreter *PythonInterpreter::instance ()
+{
+  return sp_pya_interpreter;
 }
 
 void 
@@ -162,11 +171,5 @@ PythonInterpreter::eval_expr (const char *, const char *file, int line, int)
   return tl::Variant ();
 }
 
-PythonInterpreter *
-PythonInterpreter::instance ()
-{
-  return 0;
-}
-
 }
 
diff --git a/src/pyastub/pya.h b/src/pyastub/pya.h
index 6e0c2e144..da5a48b92 100644
--- a/src/pyastub/pya.h
+++ b/src/pyastub/pya.h
@@ -168,10 +168,9 @@ public:
   static void initialize ();
 
   /**
-   *  @brief Always returns 0 
+   *  @brief Returns the singleton reference
    */
   static PythonInterpreter *instance ();
-
 };
 
 }
diff --git a/src/pyastub/pyastub.pro b/src/pyastub/pyastub.pro
index 5aa72a343..78e2be02d 100644
--- a/src/pyastub/pyastub.pro
+++ b/src/pyastub/pyastub.pro
@@ -13,5 +13,6 @@ DEPENDPATH += $$TL_INC $$GSI_INC
 LIBS += -L$$DESTDIR -lklayout_tl -lklayout_gsi
 
 HEADERS += \
-    pyaCommon.h
+    pyaCommon.h \
+    pya.h
 
diff --git a/src/rbastub/rba.cc b/src/rbastub/rba.cc
index 02398bfb0..48619942b 100644
--- a/src/rbastub/rba.cc
+++ b/src/rbastub/rba.cc
@@ -30,14 +30,23 @@ static void fail (const char *file, int line)
   throw tl::ScriptError (tl::to_string (QObject::tr ("Ruby support not compiled in")).c_str (), file, line, "missing_feature", std::vector<tl::BacktraceElement> ());
 }
 
-RubyInterpreter::RubyInterpreter () 
-{ 
-  // .. nothing ..
+static RubyInterpreter *sp_rba_interpreter = 0;
+
+RubyInterpreter::RubyInterpreter ()
+{
+  tl_assert (! sp_rba_interpreter);
+  sp_rba_interpreter = this;
 }
 
-RubyInterpreter::~RubyInterpreter () 
+RubyInterpreter::~RubyInterpreter ()
 {
-  // .. nothing ..
+  //  This prevents reinitialization
+  sp_rba_interpreter = reinterpret_cast<RubyInterpreter *> (1);
+}
+
+RubyInterpreter *RubyInterpreter::instance ()
+{
+  return sp_rba_interpreter;
 }
 
 void
diff --git a/src/rbastub/rba.h b/src/rbastub/rba.h
index 1644df201..3985b4d6b 100644
--- a/src/rbastub/rba.h
+++ b/src/rbastub/rba.h
@@ -150,6 +150,11 @@ public:
    */
   std::string version () const;
 
+  /**
+   *  @brief The instance of the Ruby interpreter
+   */
+  static RubyInterpreter *instance ();
+
   /**
    *  @brief Provide a first (basic) initialization and continue with the "main_cont" function internally
    */
diff --git a/src/rbastub/rbastub.pro b/src/rbastub/rbastub.pro
index 328245d8d..25b34917f 100644
--- a/src/rbastub/rbastub.pro
+++ b/src/rbastub/rbastub.pro
@@ -6,7 +6,7 @@ include($$PWD/../lib.pri)
 
 DEFINES += MAKE_RBA_LIBRARY
 
-HEADERS = rbaCommon.h
+HEADERS = rbaCommon.h rba.h
 
 SOURCES = rba.cc