diff --git a/sparta/sparta/parsers/ConfigEmitterYAML.hpp b/sparta/sparta/parsers/ConfigEmitterYAML.hpp
index 1b125ab36b..4734509064 100644
--- a/sparta/sparta/parsers/ConfigEmitterYAML.hpp
+++ b/sparta/sparta/parsers/ConfigEmitterYAML.hpp
@@ -86,7 +86,6 @@ class YAML : public ConfigEmitter
     {
         sparta_assert(emitter_ == nullptr);
         sparta_assert(device_tree);
-        sparta_assert(extensions_ptree);
 
         if(verbose){
             std::cout << "Writing parameters to \"" << filename_ << "\"" << std::endl;
@@ -108,22 +107,24 @@ class YAML : public ConfigEmitter
 
         handleNode_(device_tree, verbose);
 
-        // Note we use the ParameterTree to get the tree node extensions instead
-        // of the device tree since using the device tree might serialize an extension
-        // defn of:
-        //
-        //   top.cpu.core*.extension.core_extensions:
-        //       name: value
-        //       name: value
-        //
-        // As:
-        //
-        //   top.cpu.core0.extension.core_extensions:
-        //       name: value
-        //       name: value
-        //
-        // But the ParameterTree retains the wildcards in the path.
-        handleNode_(extensions_ptree->getRoot());
+        if (extensions_ptree) {
+            // Note we use the ParameterTree to get the tree node extensions instead
+            // of the device tree since using the device tree might serialize an extension
+            // defn of:
+            //
+            //   top.cpu.core*.extension.core_extensions:
+            //       name: value
+            //       name: value
+            //
+            // As:
+            //
+            //   top.cpu.core0.extension.core_extensions:
+            //       name: value
+            //       name: value
+            //
+            // But the ParameterTree retains the wildcards in the path.
+            handleNode_(extensions_ptree->getRoot());
+        }
 
         *emitter_ << YP::EndDoc;
         sparta_assert(emitter_->good());
diff --git a/sparta/test/TreeNode/TreeNode_test.cpp b/sparta/test/TreeNode/TreeNode_test.cpp
index b7d791a076..4bcd26c32e 100644
--- a/sparta/test/TreeNode/TreeNode_test.cpp
+++ b/sparta/test/TreeNode/TreeNode_test.cpp
@@ -1103,7 +1103,7 @@ int main()
         sparta::ConfigEmitter::YAML param_out(filename_orig,
                                             true); // verbose
 
-        EXPECT_NOTHROW(param_out.addParameters(&top, true)); // verbose
+        EXPECT_NOTHROW(param_out.addParameters(&top, nullptr, true)); // verbose
 
         // Ensure taht the read count on this crazy parameter has not changed
         // when emitting the YAML
@@ -1128,7 +1128,7 @@ int main()
             // Store Parameter Tree
             sparta::ConfigEmitter::YAML param_out(filename_new,
                                                 false); // Terse
-            EXPECT_NOTHROW(param_out.addParameters(&top, false));
+            EXPECT_NOTHROW(param_out.addParameters(&top, nullptr, false));
 
             // Reset read counts to write them again
             recurs_reset(&top);
@@ -1144,7 +1144,7 @@ int main()
             // Store Parameter Tree
             sparta::ConfigEmitter::YAML param_out(filename_new,
                                                 true); // Verbose
-            EXPECT_NOTHROW(param_out.addParameters(&top, false));
+            EXPECT_NOTHROW(param_out.addParameters(&top, nullptr, false));
 
             // Reset read counts to write them again
             recurs_reset(&top);