diff --git a/lib/builder.js b/lib/builder.js
index d8735a3..9222d72 100644
--- a/lib/builder.js
+++ b/lib/builder.js
@@ -151,7 +151,7 @@ Builder.prototype.reset = function(baseLoader) {
 
   var loaderConfig = loader.config;
   loader.config = function(cfg) {
-    loaderConfig.call(loader, cfg);
+    loaderConfig.call(this, cfg);
     loader.pluginLoader.config(cfg);
     loader.configHash = generateConfigHash(loader);
   };
diff --git a/lib/trace.js b/lib/trace.js
index 247377f..2b1c87b 100644
--- a/lib/trace.js
+++ b/lib/trace.js
@@ -567,11 +567,11 @@ function toCanonicalConditionalEnv(conditionalEnv) {
   return Promise.all(Object.keys(conditionalEnv).map(function(m) {
     var negate = m[0] == '~';
     var exportIndex = m.lastIndexOf('|');
-    var moduleName = m.substring(negate, exportIndex != -1 && exportIndex);
+    var moduleName = m.substring(negate, exportIndex != -1 ? exportIndex : m.length);
 
     return loader.normalize(moduleName)
     .then(function(normalized) {
-      var canonicalCondition = (negate ? '~' : '') + getCanonicalName(loader, normalized) + (exportIndex != -1 ? m.substr(exportIndex) : '');
+      var canonicalCondition = (negate ? '~' : '') + getCanonicalName(loader, normalized) + (exportIndex != -1 ? m.substr(exportIndex) : '|default');
       canonicalConditionalEnv[canonicalCondition] = conditionalEnv[m];
     });
   }))