diff --git a/tools/commands-packages.js b/tools/commands-packages.js
index 62b09b37bd..8debc08b16 100644
--- a/tools/commands-packages.js
+++ b/tools/commands-packages.js
@@ -2310,23 +2310,26 @@ main.registerCommand({
   var releaseNameAndVersion = options.args[0];
   var outputDirectory = options.args[1];
 
-  var parsed = utils.splitConstraint(releaseNameAndVersion);
-  if (!parsed.constraint)
-    throw new main.ShowUsage;
+  var trackAndVersion = utils.releaseName(releaseNameAndVersion);
+  var releaseTrack = trackAndVersion[0];
+  var releaseVersion = trackAndVersion[1];
 
   var release = catalog.official.getReleaseVersion(
-    parsed.package, parsed.constraint);
+    releaseTrack, releaseVersion);
   if (!release) {
     // XXX this could also mean package unknown.
     Console.error('Release unknown: ' + releaseNameAndVersion + '');
     return 1;
   }
 
-  var toolPkg = release.tool && utils.splitConstraint(release.tool);
-  if (! (toolPkg && toolPkg.constraint))
-    throw new Error("bad tool in release: " + toolPkg);
+  var toolConstraint = release.tool && utils.parseConstraint(release.tool);
+  if (! (toolConstraint && utils.isSimpleConstraint(toolConstraint)))
+    throw new Error("bad tool in release: " + release.tool);
+  var toolPackage = toolConstraint.name;
+  var toolVersion = toolConstraint.constraints[0].version;
+
   var toolPkgBuilds = catalog.official.getAllBuilds(
-    toolPkg.package, toolPkg.constraint);
+    toolPkgBuilds, toolVersion);
   if (!toolPkgBuilds) {
     // XXX this could also mean package unknown.
     Console.error('Tool version unknown: ' + release.tool + '');
@@ -2398,7 +2401,7 @@ main.registerCommand({
   // so we should ensure that once it is downloaded, it knows it is recommended
   // rather than having a little identity crisis and thinking that a past
   // release is the latest recommended until it manages to sync.
-  tmpCatalog.forceRecommendRelease(parsed.package, parsed.constraint);
+  tmpCatalog.forceRecommendRelease(releaseTrack, releaseVersion);
   tmpCatalog.closePermanently();
   if (fs.existsSync(tmpDataFile + '-wal')) {
     throw Error("Write-ahead log still exists for " + tmpDataFile
@@ -2410,12 +2413,12 @@ main.registerCommand({
     // We're going to build and tar up a tropohouse in a temporary directory.
     var tmpTropo = new tropohouse.Tropohouse(path.join(tmpdir, '.meteor'));
     buildmessage.enterJob({
-      title: "Downloading tool package " + toolPkg.package + "@" +
-        toolPkg.constraint
+      title: "Downloading tool package " + toolPackage + "@" +
+        toolVersion
     }, function () {
       tmpTropo.maybeDownloadPackageForArchitectures({
-        packageName: toolPkg.package,
-        version: toolPkg.constraint,
+        packageName: toolPackage,
+        version: toolVersion,
         architectures: [osArch]  // XXX 'web.browser' too?
       });
     });
@@ -2441,15 +2444,15 @@ main.registerCommand({
     // Create the top-level 'meteor' symlink, which links to the latest tool's
     // meteor shell script.
     var toolIsopackPath =
-          tmpTropo.packagePath(toolPkg.package, toolPkg.constraint);
+          tmpTropo.packagePath(toolPackage, toolVersion);
     var toolIsopack = new isopack.Isopack;
-    toolIsopack.initFromPath(toolPkg.package, toolIsopackPath);
+    toolIsopack.initFromPath(toolPackage, toolIsopackPath);
     var toolRecord = _.findWhere(toolIsopack.toolsOnDisk, {arch: osArch});
     if (!toolRecord)
       throw Error("missing tool for " + osArch);
     fs.symlinkSync(
       path.join(
-        tmpTropo.packagePath(toolPkg.package, toolPkg.constraint, true),
+        tmpTropo.packagePath(toolPackage, toolVersion, true),
         toolRecord.path,
         'meteor'),
       path.join(tmpTropo.root, 'meteor'));
diff --git a/tools/package-source.js b/tools/package-source.js
index 25e86e0830..bf74705a0a 100644
--- a/tools/package-source.js
+++ b/tools/package-source.js
@@ -94,6 +94,13 @@ var mapWhereToArch = function (where) {
   }
 };
 
+var splitConstraint = function (c) {
+  // XXX print error better (w/ buildmessage?)?
+  var parsed = utils.parseConstraint(c);
+  return { package: parsed.name,
+           constraint: parsed.constraintString || null };
+};
+
 ///////////////////////////////////////////////////////////////////////////////
 // SourceArch
 ///////////////////////////////////////////////////////////////////////////////
@@ -376,7 +383,7 @@ _.extend(PackageSource.prototype, {
     var sourceArch = new SourceArch(self, {
       kind: options.kind,
       arch: "os",
-      uses: _.map(options.use, utils.splitConstraint),
+      uses: _.map(options.use, splitConstraint),
       getSourcesFunc: function () { return sources; },
       nodeModulesPath: nodeModulesPath
     });
@@ -1784,7 +1791,7 @@ _.extend(PackageSource.prototype, {
       // info.use is currently just an array of strings, and there's
       // no way to specify weak/unordered. Much like an app.
       _.each(info.use, function (spec) {
-        var parsedSpec = utils.splitConstraint(spec);
+        var parsedSpec = splitConstraint(spec);
         packages[parsedSpec.package] = true;
       });
     });
@@ -1980,7 +1987,7 @@ _.extend(PackageSource.prototype, {
 
     _.each(self.pluginInfo, function (info) {
       _.each(info.use, function (spec) {
-        var parsedSpec = utils.splitConstraint(spec);
+        var parsedSpec = splitConstraint(spec);
         if (!_.has(dependencies, parsedSpec.package)) {
           dependencies[parsedSpec.package] = {
             constraint: null,
diff --git a/tools/project-context.js b/tools/project-context.js
index 17ce6a610e..d5d21ce814 100644
--- a/tools/project-context.js
+++ b/tools/project-context.js
@@ -680,8 +680,7 @@ _.extend(exports.PackageMapFile.prototype, {
 
       // We expect this constraint to be "foo@1.2.3", not a lack of a constraint
       // or something with "||" or "@=".
-      if (constraint.constraints.length !== 1 ||
-          constraint.constraints[0].type !== "compatible-with") {
+      if (! utils.isSimpleConstraint(constraint)) {
         buildmessage.error("Bad version: " + line, {
           // XXX should this be relative?
           file: self.filename
diff --git a/tools/utils.js b/tools/utils.js
index 9fb3c6c4e5..13cd057c5b 100644
--- a/tools/utils.js
+++ b/tools/utils.js
@@ -252,16 +252,10 @@ exports.parseConstraint = function (constraintString, options) {
 exports.parseVersionConstraint = packageVersionParser.parseVersionConstraint;
 exports.validatePackageName = packageVersionParser.validatePackageName;
 
-// XXX should unify this with utils.parseConstraint
-exports.splitConstraint = function (constraint) {
-  var m = constraint.split("@");
-  var ret = { package: m[0] };
-  if (m.length > 1) {
-    ret.constraint = m[1];
-  } else {
-    ret.constraint = null;
-  }
-  return ret;
+// Returns true if the parsed constraint was just a@b with no `=` or `||`.
+exports.isSimpleConstraint = function (parsedConstraint) {
+  return parsedConstraint.constraints.length === 1 &&
+    parsedConstraint.constraints[0].type === "compatible-with";
 };