diff --git a/packages/modules-runtime/client.js b/packages/modules-runtime/client.js
new file mode 100644
index 0000000000..d902671864
--- /dev/null
+++ b/packages/modules-runtime/client.js
@@ -0,0 +1,5 @@
+// On the client, make package resolution prefer the "browser" field of
+// package.json files to the "main" field.
+makeInstallerOptions.browser = true;
+
+meteorInstall = makeInstaller(makeInstallerOptions);
diff --git a/packages/modules-runtime/modules-runtime.js b/packages/modules-runtime/modules-runtime.js
deleted file mode 100644
index da38e75648..0000000000
--- a/packages/modules-runtime/modules-runtime.js
+++ /dev/null
@@ -1,86 +0,0 @@
-var options = {};
-var hasOwn = options.hasOwnProperty;
-
-// RegExp matching strings that don't start with a `.` or a `/`.
-var topLevelIdPattern = /^[^./]/;
-
-if (typeof Profile === "function" &&
-    process.env.METEOR_PROFILE) {
-  options.wrapRequire = function (require) {
-    return Profile(function (id) {
-      return "require(" + JSON.stringify(id) + ")";
-    }, require);
-  };
-}
-
-// On the client, make package resolution prefer the "browser" field of
-// package.json files to the "main" field.
-options.browser = Meteor.isClient;
-
-// This function will be called whenever a module identifier that hasn't
-// been installed is required. For backwards compatibility, and so that we
-// can require binary dependencies on the server, we implement the
-// fallback in terms of Npm.require.
-options.fallback = function (id, parentId, error) {
-  // For simplicity, we honor only top-level module identifiers here.
-  // We could try to honor relative and absolute module identifiers by
-  // somehow combining `id` with `dir`, but we'd have to be really careful
-  // that the resulting modules were located in a known directory (not
-  // some arbitrary location on the file system), and we only really need
-  // the fallback for dependencies installed in node_modules directories.
-  if (topLevelIdPattern.test(id)) {
-    if (typeof Npm === "object" &&
-        typeof Npm.require === "function") {
-      return Npm.require(id);
-    }
-  }
-
-  throw error;
-};
-
-options.fallback.resolve = function (id, parentId, error) {
-  if (Meteor.isServer &&
-      topLevelIdPattern.test(id)) {
-    // Allow any top-level identifier to resolve to itself on the server,
-    // so that options.fallback can have a chance to handle it.
-    return id;
-  }
-
-  throw error;
-};
-
-meteorInstall = makeInstaller(options);
-var Mp = meteorInstall.Module.prototype;
-
-if (Meteor.isServer) {
-  Mp.useNode = function () {
-    if (typeof npmRequire !== "function") {
-      // Can't use Node if npmRequire is not defined.
-      return false;
-    }
-
-    var parts = this.id.split("/");
-    var start = 0;
-    if (parts[start] === "") ++start;
-    if (parts[start] === "node_modules" &&
-        parts[start + 1] === "meteor") {
-      start += 2;
-    }
-
-    if (parts.indexOf("node_modules", start) < 0) {
-      // Don't try to use Node for modules that aren't in node_modules
-      // directories.
-      return false;
-    }
-
-    try {
-      npmRequire.resolve(this.id);
-    } catch (e) {
-      return false;
-    }
-
-    this.exports = npmRequire(this.id);
-
-    return true;
-  };
-}
diff --git a/packages/modules-runtime/options.js b/packages/modules-runtime/options.js
new file mode 100644
index 0000000000..200b878613
--- /dev/null
+++ b/packages/modules-runtime/options.js
@@ -0,0 +1,10 @@
+makeInstallerOptions = {};
+
+if (typeof Profile === "function" &&
+    process.env.METEOR_PROFILE) {
+  makeInstallerOptions.wrapRequire = function (require) {
+    return Profile(function (id) {
+      return "require(" + JSON.stringify(id) + ")";
+    }, require);
+  };
+}
diff --git a/packages/modules-runtime/package.js b/packages/modules-runtime/package.js
index 5aff025d47..6d0735fcab 100644
--- a/packages/modules-runtime/package.js
+++ b/packages/modules-runtime/package.js
@@ -18,7 +18,10 @@ Package.onUse(function(api) {
     bare: true
   });
 
-  api.addFiles("modules-runtime.js");
+  api.addFiles("options.js");
+  api.addFiles("client.js", "client");
+  api.addFiles("server.js", "server");
+
   api.export("meteorInstall");
 });
 
diff --git a/packages/modules-runtime/server.js b/packages/modules-runtime/server.js
new file mode 100644
index 0000000000..367a60c769
--- /dev/null
+++ b/packages/modules-runtime/server.js
@@ -0,0 +1,67 @@
+// RegExp matching strings that don't start with a `.` or a `/`.
+var topLevelIdPattern = /^[^./]/;
+
+// This function will be called whenever a module identifier that hasn't
+// been installed is required. For backwards compatibility, and so that we
+// can require binary dependencies on the server, we implement the
+// fallback in terms of Npm.require.
+makeInstallerOptions.fallback = function (id, parentId, error) {
+  // For simplicity, we honor only top-level module identifiers here.
+  // We could try to honor relative and absolute module identifiers by
+  // somehow combining `id` with `dir`, but we'd have to be really careful
+  // that the resulting modules were located in a known directory (not
+  // some arbitrary location on the file system), and we only really need
+  // the fallback for dependencies installed in node_modules directories.
+  if (topLevelIdPattern.test(id)) {
+    if (typeof Npm === "object" &&
+        typeof Npm.require === "function") {
+      return Npm.require(id);
+    }
+  }
+
+  throw error;
+};
+
+makeInstallerOptions.fallback.resolve = function (id, parentId, error) {
+  if (topLevelIdPattern.test(id)) {
+    // Allow any top-level identifier to resolve to itself on the server,
+    // so that makeInstallerOptions.fallback has a chance to handle it.
+    return id;
+  }
+
+  throw error;
+};
+
+meteorInstall = makeInstaller(makeInstallerOptions);
+var Module = meteorInstall.Module;
+
+Module.prototype.useNode = function () {
+  if (typeof npmRequire !== "function") {
+    // Can't use Node if npmRequire is not defined.
+    return false;
+  }
+
+  var parts = this.id.split("/");
+  var start = 0;
+  if (parts[start] === "") ++start;
+  if (parts[start] === "node_modules" &&
+      parts[start + 1] === "meteor") {
+    start += 2;
+  }
+
+  if (parts.indexOf("node_modules", start) < 0) {
+    // Don't try to use Node for modules that aren't in node_modules
+    // directories.
+    return false;
+  }
+
+  try {
+    npmRequire.resolve(this.id);
+  } catch (e) {
+    return false;
+  }
+
+  this.exports = npmRequire(this.id);
+
+  return true;
+};