diff --git a/Makefile b/Makefile
index b0d23b89..f72da46f 100755
--- a/Makefile
+++ b/Makefile
@@ -70,9 +70,9 @@ dist/system.src.js: lib/*.js $(ESML)/*.js
 				lib/cjs.js \
 				lib/amd.js \
 				lib/map.js \
+				lib/package.js \
 				lib/plugins.js \
 				lib/alias.js \
-				lib/package.js \
 				lib/bundles.js \
 				lib/depCache.js \
 				lib/conditionals.js \
@@ -97,9 +97,9 @@ dist/system-prod.src.js: lib/*.js $(ESML)/*.js
 				lib/register.js \
 				lib/global-helpers.js \
 				lib/map.js \
+				lib/package.js \
 				lib/plugins.js \
 				lib/alias.js \
-				lib/package.js \
 				lib/bundles.js \
 				lib/depCache.js \
 				lib/conditionals.js \
diff --git a/lib/map.js b/lib/map.js
index 680c5730..0f4f25e6 100644
--- a/lib/map.js
+++ b/lib/map.js
@@ -4,134 +4,46 @@
   Provides map configuration through
     System.map['jquery'] = 'some/module/map'
 
-  As well as contextual map config through
-    System.map['bootstrap'] = {
-      jquery: 'some/module/map2'
-    }
-
-  Note that this applies for subpaths, just like RequireJS
+  Note that this applies for subpaths, just like RequireJS:
 
   jquery      -> 'some/module/map'
   jquery/path -> 'some/module/map/path'
   bootstrap   -> 'bootstrap'
 
-  Inside any module name of the form 'bootstrap' or 'bootstrap/*'
-    jquery    -> 'some/module/map2'
-    jquery/p  -> 'some/module/map2/p'
-
-  Maps are carefully applied from most specific contextual map, to least specific global map
+  The most specific map is always taken, as longest path length
 */
-(function() {
+hookConstructor(function(constructor) {
+  return function() {
+    constructor.call(this);
+    this.map = {};
+  };
+});
 
-  hookConstructor(function(constructor) {
-    return function() {
-      constructor.call(this);
-      this.map = {};
-    };
-  });
+hook('normalize', function(normalize) {
+  return function(name, parentName, parentAddress) {
+    var loader = this;
+    return Promise.resolve(normalize.call(loader, name, parentName, parentAddress))
+    .then(function(name) {
+      var bestMatch, bestMatchLength = 0;
 
-  // return if prefix parts (separated by '/') match the name
-  // eg prefixMatch('jquery/some/thing', 'jquery') -> true
-  //    prefixMatch('jqueryhere/', 'jquery') -> false
-  function prefixMatch(name, prefix) {
-    if (name.length < prefix.length)
-      return false;
-    if (name.substr(0, prefix.length) != prefix)
-      return false;
-    if (name[prefix.length] && name[prefix.length] != '/')
-      return false;
-    return true;
-  }
-
-  // get the depth of a given path
-  // eg pathLen('some/name') -> 2
-  function pathLen(name) {
-    var len = 1;
-    for (var i = 0, l = name.length; i < l; i++)
-      if (name[i] === '/')
-        len++;
-    return len;
-  }
-
-  function doMap(name, matchLen, map) {
-    return map + name.substr(matchLen);
-  }
-
-  // given a relative-resolved module name and normalized parent name,
-  // apply the map configuration
-  function applyMap(name, parentName, loader) {
-    var curMatch, curMatchLength = 0;
-    var curParent, curParentMatchLength = 0;
-    var tmpParentLength, tmpPrefixLength;
-    var subPath;
-    var nameParts;
-    
-    // first find most specific contextual match
-    if (parentName) {
+      // now do the global map
       for (var p in loader.map) {
-        var curMap = loader.map[p];
-        if (typeof curMap != 'object')
-          continue;
+        if (typeof loader.map[p] != 'string')
+          throw new TypeError('Map configuration no longer permits object submaps. Use package map instead (`System.packages[name].map`).');
 
-        // most specific parent match wins first
-        if (!prefixMatch(parentName, p))
-          continue;
-
-        tmpParentLength = pathLen(p);
-        if (tmpParentLength <= curParentMatchLength)
-          continue;
-
-        for (var q in curMap) {
-          // most specific name match wins
-          if (!prefixMatch(name, q))
+        if (name.substr(0, p.length) == p && (name.length == p.length || name[p.length] == '/')) {
+          var curMatchLength = p.split('/').length;
+          if (curMatchLength <= bestMatchLength)
             continue;
-          tmpPrefixLength = pathLen(q);
-          if (tmpPrefixLength <= curMatchLength)
-            continue;
-
-          curMatch = q;
-          curMatchLength = tmpPrefixLength;
-          curParent = p;
-          curParentMatchLength = tmpParentLength;
+          bestMatch = p;
+          bestMatchLength = curMatchLength;
         }
       }
-    }
 
-    // if we found a contextual match, apply it now
-    if (curMatch)
-      return doMap(name, curMatch.length, loader.map[curParent][curMatch]);
+      if (bestMatch)
+        return loader.map[bestMatch] + name.substr(bestMatch.length);
 
-    // now do the global map
-    for (var p in loader.map) {
-      var curMap = loader.map[p];
-      if (typeof curMap != 'string')
-        continue;
-
-      if (!prefixMatch(name, p))
-        continue;
-
-      var tmpPrefixLength = pathLen(p);
-
-      if (tmpPrefixLength <= curMatchLength)
-        continue;
-
-      curMatch = p;
-      curMatchLength = tmpPrefixLength;
-    }
-
-    if (curMatch)
-      return doMap(name, curMatch.length, loader.map[curMatch]);
-
-    return name;
-  }
-
-  hook('normalize', function(normalize) {
-    return function(name, parentName, parentAddress) {
-      var loader = this;
-      return Promise.resolve(normalize.call(loader, name, parentName, parentAddress))
-      .then(function(name) {
-        return applyMap(name, parentName, loader);
-      });
-    };
-  });
-})();
+      return name;
+    });
+  };
+});
diff --git a/lib/package.js b/lib/package.js
index b318f73c..040f2a2b 100644
--- a/lib/package.js
+++ b/lib/package.js
@@ -7,47 +7,35 @@
  *
  * Example:
  *
- * System.package('jquery', {
- *   main: 'index.js',
- *   format: 'amd',
- *   defaultJSExtension: true,
- *   modules: {
- *     'vendor/sizzle.js': {
- *       format: 'global'
- *     }
- *   },
- *   map: {
- *     // map internal require('sizzle') to local require('./vendor/sizzle')
- *     sizzle: './vendor/sizzle.js',
- *
- *     // map external require of 'jquery/vendor/another.js' to 'another/index.js'
- *     './vendor/another.js': 'another/index.js'
- *   }
- * });
- *
- * Is equivalent to:
- * 
  * System.config({
- *   meta: {
- *     'jquery/*': {
- *       format: 'amd',
- *     }
- *     'jquery/vendor/sizzle.js': {
- *       format: 'global'
- *     }
- *   },
- *   map: {
- *     'jquery/vendor/another.js': 'another/index.js'
+ *   packages: {
  *     jquery: {
- *       sizzle: 'jquery/vendor/sizzle.js'
+ *       main: 'index.js', // this main is actually set by default
+ *       format: 'amd',
+ *       defaultExtension: 'js',
+ *       meta: {
+ *         '*.ts': {
+ *           plugin: 'typescript'
+ *         },
+ *         'vendor/sizzle.js': {
+ *           format: 'global'
+ *         }
+ *       },
+ *       map: {
+ *         // map internal require('sizzle') to local require('./vendor/sizzle')
+ *         sizzle: './vendor/sizzle.js',
+ *
+ *         // map any internal or external require of 'jquery/vendor/another' to 'another/index.js'
+ *         './vendor/another': 'another/index.js'
+ *       }
  *     }
  *   }
  * });
  *
- * With normalization hooks providing main and defaultExtension support
- * so that:
- *   import 'jquery' => import 'jquery/index.js'
- *   import 'jquery/module' => import 'jquery/module.js'
+ * Then:
+ *   import 'jquery'                -> jquery/index.js
+ *   import 'jquery/submodule'      -> jquery/submodule.js
+ *   import 'jquery/vendor/another' -> jquery/another/index.js
  *
  * In addition, the following meta properties will be allowed to be package
  * -relative as well in the package meta config:
@@ -61,86 +49,136 @@
   hookConstructor(function(constructor) {
     return function() {
       constructor.call(this);
-      this.packageMains = {};
-      this.packageDefaultJSExtensions = {};
+      this.packages = {};
     };
   });
 
+  function getPackage(name) {
+    for (var p in this.packages) {
+      if (name.substr(0, p.length) === p && (name.length === p.length || name[p.length] === '/'))
+        return p;
+    }
+  }
+
+  function applyMap(map, name) {
+    var bestMatch, bestMatchLength = 0;
+    
+    for (var p in map) {
+      if (name.substr(0, p.length) == p && (name.length == p.length || name[p.length] == '/')) {
+        var curMatchLength = p.split('/').length;
+        if (curMatchLength <= bestMatchLength)
+          continue;
+        bestMatch = p;
+        bestMatchLength = curMatchLength;
+      }
+    }
+    if (bestMatch)
+      name = map[bestMatch] + name.substr(bestMatch.length);
+
+    return name;
+  }
+
   hook('normalize', function(normalize) {
     return function(name, parentName, parentAddress) {
       var loader = this;
+
+      // apply contextual package map first
+      if (parentName)
+        var parentPackage = getPackage.call(loader, parentName);
+
+      if (parentPackage && name[0] !== '.') {
+        var parentMap = loader.packages[parentPackage].map;
+        if (parentMap) {
+          name = applyMap(parentMap, name);
+
+          // relative maps are package-relative
+          if (name[0] === '.')
+            parentName = parentPackage;
+        }
+      }
+
+      // apply global map, relative normalization
       return normalize.call(loader, name, parentName, parentAddress)
       .then(function(normalized) {
-        // main
-        if (loader.packageMains[normalized])
-          normalized = normalized + '/' + loader.packageMains[normalized];
+        // check if we are inside a package
+        var pkgName = getPackage.call(loader, normalized);
 
-        // defaultJSExtension
-        if (normalized.split('/').pop().indexOf('.') == -1) {
-          for (var d in loader.packageDefaultExtensions) {
-            if (normalized.substr(0, d.length + 1) == d + '/') {
-              normalized += '.js';
-              break;
-            }
+        if (pkgName) {
+          var pkg = loader.packages[pkgName];
+
+          // main
+          if (pkgName === normalized)
+            normalized += '/' + (pkg.main || 'index.js');
+
+          // relative maps
+          if (pkg.map) {
+            normalized = pkgName + applyMap(pkg.map, '.' + normalized.substr(pkgName.length)).substr(1);
+
+            // normalize package-relative maps
+            if (normalized.substr(0, 2) == './')
+              normalized = pkgName + normalized.substr(1);
           }
+
+          // defaultExtension
+          if (pkg.defaultExtension 
+              && (!pkg.meta || !pkg.meta[normalized.substr(pkgName.length + 1)])
+              && normalized.split('/').pop().indexOf('.') == -1)
+            normalized += '.' + pkg.defaultExtension;
         }
+
         return normalized;
       });
     };
   });
 
-  SystemJSLoader.prototype.package = function(p, pkgConfig) {
-    // main
-    var main = pkgCfg.main;
-    if (main)
-      this.packageMains[p] = main.substr(0, 2) == './' ? main.substr(2) : main;
-
-    // defaultJSExtension
-    if (pkgCfg.defaultJSExtension)
-      this.packageDefaultJSExtensions[p] = true;
-
-    // format
-    if (pkgCfg.format) {
-      var formatMeta = this.meta[p + '/*'] || {};
-      formatMeta.format = pkgCfg.format;
-      this.meta[p + '/*'] = formatMeta;
+  function extend(a, b, overwrite) {
+    for (var p in b) {
+      if (overwrite || !(p in a))
+        a[p] = b[p];
     }
+  }
 
-    // meta
-    for (var m in pkgCfg.modules) {
-      var meta = this.meta[p + '/' + m] || {};
-      var pkgMeta = pkgCfg.modules[m];
-      // alias shorthand
-      if (typeof pkgMeta === 'string')
-        pkgMeta = { alias: pkgMeta };
-      for (var p in pkgMeta) {
-        // plugin and alias can be package-relative
-        if ((p === 'plugin' || p === 'alias')
-            && pkgMeta[p].substr(0, 2) == './')
-          meta[p] = p + pkgMeta[p].substr(1);
-        else
-          meta[p] = pkgMeta[p];
-      }
-      this.meta[p + '/' + m] = meta;
-    }
+  hook('locate', function(locate) {
+    return function(load) {
+      var loader = this;
+      return Promise.resolve(locate.call(this, load))
+      .then(function(address) {
+        var pkgName = getPackage.call(loader, load.name);
+        if (pkgName) {
+          var pkg = loader.packages[pkgName];
+          
+          // format
+          if (pkg.format)
+            load.metadata.format = load.metadata.format || pkg.format;
 
-    // map
-    for (var m in pkgCfg.map) {
-      var target = pkgCfg.map[m];
-      if (target.substr(0, 2) == './')
-        target = p + target.substr(1);
+          if (pkg.meta) {
+            // wildcard meta
+            var meta = {};
+            var bestDepth = 0;
+            var wildcardIndex;
+            for (var module in pkg.meta) {
+              wildcardIndex = indexOf.call(module, '*');
+              if (wildcardIndex === -1)
+                continue;
+              if (module.substr(0, wildcardIndex) === load.name.substr(0, wildcardIndex)
+                  && module.substr(wildcardIndex + 1) === load.name.substr(load.name.length - module.length + wildcardIndex + 1)) {
+                var depth = module.split('/').length;
+                if (depth > bestDepth)
+                  bestDetph = depth;
+                extend(meta, pkg.meta[module], bestDepth == depth);
+              }
+            }
+            // exact meta
+            if (pkg.meta[load.name])
+              extend(meta, meta[load.name], true);
+            
+            extend(load.metadata, meta);
+          }
+        }
 
-      // package-relative base map
-      if (m.substr(0, 2) == './') {
-        this.map[p + m.substr(1)] = target;
-      }
-
-      // package-contextual map
-      else {
-        this.map[p] = this.map[p] || {};
-        this.map[p][m] = target;
-      }
-    }
-  };
+        return address;
+      });
+    };
+  });
 
 })();
\ No newline at end of file
diff --git a/test/test.js b/test/test.js
index dc6bf8d9..6095e953 100644
--- a/test/test.js
+++ b/test/test.js
@@ -155,34 +155,31 @@ asyncTest('Map configuration subpath', function() {
   }, err);
 });
 
-asyncTest('Contextual map configuration', function() {
-  System.map['tests/contextual-map.js'] = {
-    maptest: 'tests/contextual-map-dep.js'
+asyncTest('Package map configuration', function() {
+  System.packages['tests/contextual-test'] = {
+    main: 'contextual-map.js',
+    map: {
+      maptest: 'tests/contextual-map-dep.js'
+    }
   };
-  System['import']('tests/contextual-map.js').then(function(m) {
+  System['import']('tests/contextual-test').then(function(m) {
     ok(m.mapdep == 'mapdep', 'Contextual map dep not loaded');
     start();
   }, err);
 });
 
-asyncTest('Submodule contextual map configuration', function() {
-  System.map['tests/subcontextual-map'] = {
-    dep: 'tests/subcontextual-mapdep.js'
+asyncTest('Package map with shim', function() {
+  System.packages['tests/shim-package'] = {
+    meta: {
+      '*': {
+        deps: ['shim-map-dep']
+      }
+    },
+    map: {
+      'shim-map-dep': 'tests/shim-map-test-dep.js'
+    }
   };
-  System['import']('tests/subcontextual-map/submodule.js').then(function(m) {
-    ok(m == 'submapdep', 'Submodule contextual map not loaded');
-    start();
-  }, err);
-});
-
-asyncTest('Contextual map with shim', function() {
-  System.meta['tests/shim-map-test.js'] = {
-    deps: ['shim-map-dep']
-  };
-  System.map['tests/shim-map-test.js'] = {
-    'shim-map-dep': 'tests/shim-map-test-dep.js'
-  };
-  System['import']('tests/shim-map-test.js').then(function(m) {
+  System['import']('tests/shim-package/shim-map-test.js').then(function(m) {
     ok(m == 'depvalue', 'shim dep not loaded');
     start();
   }, err);
diff --git a/test/tests/contextual-map.js b/test/tests/contextual-test/contextual-map.js
similarity index 100%
rename from test/tests/contextual-map.js
rename to test/tests/contextual-test/contextual-map.js
diff --git a/test/tests/shim-map-test.js b/test/tests/shim-package/shim-map-test.js
similarity index 100%
rename from test/tests/shim-map-test.js
rename to test/tests/shim-package/shim-map-test.js