There is no need for unlinking, reducing moving parts

lib/core/Manager.js

@@ -9,6 +9,7 @@ var PackageRepository = require('./PackageRepository');
 var semver = require('../util/semver');
 var copy = require('../util/copy');
 var createError = require('../util/createError');
+var dependencyLinker = require('../util/dependencyLinker');
 var scripts = require('./scripts');
 
 function Manager(config, logger) {
@@ -190,7 +191,13 @@ Manager.prototype.install = function (json) {
                 return dissected;
             }, this);
         }, that);
-
+    })
+    .then(function () {
+        // Create symlinks for sub-dependencies
+        var flattened = mout.object.mixIn({}, that._installed, that._dissected);
+        return dependencyLinker.link(flattened, that._config, that._logger);
+    })
+    .then(function () {
         // Resolve with meaningful data
         return mout.object.map(that._dissected, function (decEndpoint) {
             return this.toData(decEndpoint);

lib/util/createLink.js

@@ -6,7 +6,9 @@ var createError = require('./createError');
 
 var isWin = process.platform === 'win32';
 
-function createLink(src, dst, type) {
+function createLink(src, dst, options) {
+    options = options || {};
+
     var dstDir = path.dirname(dst);
 
     // Create directory
@@ -26,7 +28,12 @@ function createLink(src, dst, type) {
     })
     // Create symlink
     .then(function (stat) {
-        type = type || (stat.isDirectory() ? 'dir' : 'file');
+        var type = options.type || (stat.isDirectory() ? 'dir' : 'file');
+        if (options.relative && !isWin) {
+            src = path.relative(path.dirname(dst), src);
+        } else {
+            src = path.resolve(src);
+        }
 
         return Q.nfcall(fs.symlink, src, dst, type)
         .fail(function (err) {

lib/util/dependencyLinker.js

@@ -0,0 +1,39 @@
+var Q = require('q');
+var Config = require('bower-config');
+var createLink = require('../util/createLink');
+var readJson = require('../util/readJson');
+var path = require('path');
+var fs = require('graceful-fs');
+
+module.exports.link = function (packages, config, logger) {
+    var rootComponentsDir = path.join(config.cwd, config.directory);
+
+    // create links for new packages and make sure that existing
+    // ones has all dependencies linked
+    var promises = Object.keys(packages).map(function (depName) {
+        var dep = packages[depName];
+        var depPath = dep.canonicalDir || path.join(rootComponentsDir, dep.name);
+        var conf = Config.read(depPath);
+        var componentsDir = path.join(conf.cwd, conf.directory);
+
+        return readJson(depPath)
+        .spread(function (json, deprecated, assumed) {
+            if (json.dependencies) {
+                return Q.all(Object.keys(json.dependencies || {}).map(function (d) {
+                    var dst = path.join(componentsDir, d);
+                    var src = path.join(rootComponentsDir, d);
+
+                    return Q.nfcall(fs.stat, dst)
+                    .fail(function () {
+                        logger.info('dep-link', d, {
+                            name: json.name + '#' + d
+                        });
+                        return createLink(src, dst, {relative: true});
+                    });
+                }));
+            }
+        });
+    });
+
+    return Q.all(promises);
+};