diff --git a/arduino-core/lib/commons-codec-1.7.jar b/arduino-core/lib/commons-codec-1.7.jar
new file mode 100644
index 000000000..efa7f7291
Binary files /dev/null and b/arduino-core/lib/commons-codec-1.7.jar differ
diff --git a/arduino-core/src/cc/arduino/packages/contributions/DownloadableContributionsDownloader.java b/arduino-core/src/cc/arduino/packages/contributions/DownloadableContributionsDownloader.java
new file mode 100644
index 000000000..5e46a0575
--- /dev/null
+++ b/arduino-core/src/cc/arduino/packages/contributions/DownloadableContributionsDownloader.java
@@ -0,0 +1,106 @@
+/*
+ * This file is part of Arduino.
+ *
+ * Copyright 2014 Arduino LLC (http://www.arduino.cc/)
+ *
+ * Arduino is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction.  Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License.  This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ */
+package cc.arduino.packages.contributions;
+
+import static processing.app.I18n._;
+import static processing.app.I18n.format;
+
+import java.io.File;
+import java.net.URL;
+import java.util.Observable;
+import java.util.Observer;
+
+import cc.arduino.utils.FileHash;
+import cc.arduino.utils.Progress;
+import cc.arduino.utils.network.FileDownloader;
+
+public class DownloadableContributionsDownloader {
+
+  private File stagingFolder;
+
+  public DownloadableContributionsDownloader(File _stagingFolder) {
+    stagingFolder = _stagingFolder;
+  }
+
+  public File download(DownloadableContribution contribution,
+                       final Progress progress, final String statusText)
+      throws Exception {
+    URL url = new URL(contribution.getUrl());
+    final File outputFile = new File(stagingFolder, contribution.getArchiveFileName());
+
+    // Ensure the existence of staging folder
+    stagingFolder.mkdirs();
+
+    // Need to download or resume downloading?
+    if (!outputFile.isFile() || (outputFile.length() < contribution.getSize())) {
+      download(url, outputFile, progress, statusText);
+    }
+
+    // Test checksum
+    progress.setStatus(_("Verifying archive integrity..."));
+    onProgress(progress);
+    String checksum = contribution.getChecksum();
+    String algo = checksum.split(":")[0];
+    if (!FileHash.hash(outputFile, algo).equals(checksum))
+      throw new Exception(_("CRC doesn't match. File is corrupted."));
+
+    contribution.setDownloaded(true);
+    contribution.setDownloadedFile(outputFile);
+    return outputFile;
+  }
+
+  public void download(URL url, File tmpFile, final Progress progress,
+                       final String statusText) throws Exception {
+    FileDownloader downloader = new FileDownloader(url, tmpFile);
+    downloader.addObserver(new Observer() {
+      @Override
+      public void update(Observable o, Object arg) {
+        FileDownloader me = (FileDownloader) o;
+        String msg = "";
+        if (me.getDownloadSize() != null) {
+          long downloaded = me.getInitialSize() + me.getDownloaded() / 1000;
+          long total = me.getInitialSize() + me.getDownloadSize() / 1000;
+          msg = format(_("Downloaded {0}kb of {1}kb."), downloaded, total);
+        }
+        progress.setStatus(statusText + " " + msg);
+        progress.setProgress(me.getProgress());
+        onProgress(progress);
+      }
+    });
+    downloader.download();
+    if (!downloader.isCompleted())
+      throw new Exception(format(_("Error dowloading {0}"), url),
+          downloader.getError());
+  }
+
+  protected void onProgress(Progress progress) {
+    // Empty
+  }
+
+}
diff --git a/arduino-core/src/cc/arduino/utils/network/FileDownloader.java b/arduino-core/src/cc/arduino/utils/network/FileDownloader.java
new file mode 100644
index 000000000..996bd8111
--- /dev/null
+++ b/arduino-core/src/cc/arduino/utils/network/FileDownloader.java
@@ -0,0 +1,214 @@
+/*
+ * This file is part of Arduino.
+ *
+ * Copyright 2014 Arduino LLC (http://www.arduino.cc/)
+ *
+ * Arduino is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction.  Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License.  This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ */
+package cc.arduino.utils.network;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.RandomAccessFile;
+import java.net.HttpURLConnection;
+import java.net.SocketTimeoutException;
+import java.net.URL;
+import java.util.Observable;
+
+import org.apache.commons.codec.binary.Base64;
+
+public class FileDownloader extends Observable {
+
+  public enum Status {
+    CONNECTING, //
+    CONNECTION_TIMEOUT_ERROR, //
+    DOWNLOADING, //
+    COMPLETE, //
+    CANCELLED, //
+    ERROR, //
+  };
+
+  private Status status;
+  private long initialSize;
+  private Long downloadSize = null;
+  private long downloaded;
+  private URL downloadUrl;
+
+  private File outputFile;
+  private InputStream stream = null;
+  private Exception error;
+
+  public FileDownloader(URL url, File file) {
+    downloadUrl = url;
+    outputFile = file;
+    downloaded = 0;
+    initialSize = 0;
+  }
+
+  public long getInitialSize() {
+    return initialSize;
+  }
+
+  public Long getDownloadSize() {
+    return downloadSize;
+  }
+
+  public void setDownloadSize(Long downloadSize) {
+    this.downloadSize = downloadSize;
+    setChanged();
+    notifyObservers();
+  }
+
+  public long getDownloaded() {
+    return downloaded;
+  }
+
+  private void setDownloaded(long downloaded) {
+    this.downloaded = downloaded;
+    setChanged();
+    notifyObservers();
+  }
+
+  public float getProgress() {
+    if (downloadSize == null)
+      return 0;
+    if (downloadSize == 0)
+      return 100;
+    return ((float) downloaded / downloadSize) * 100;
+  }
+
+  public Status getStatus() {
+    return status;
+  }
+
+  public void setStatus(Status status) {
+    this.status = status;
+    setChanged();
+    notifyObservers();
+  }
+
+  public void download() throws InterruptedException {
+    RandomAccessFile file = null;
+
+    try {
+      // Open file and seek to the end of it
+      file = new RandomAccessFile(outputFile, "rw");
+      initialSize = file.length();
+      file.seek(initialSize);
+
+      setStatus(Status.CONNECTING);
+
+      HttpURLConnection connection = (HttpURLConnection) downloadUrl
+          .openConnection();
+
+      if (downloadUrl.getUserInfo() != null) {
+        String auth = "Basic "
+                      + new String(new Base64().encode(downloadUrl
+                          .getUserInfo().getBytes()));
+        connection.setRequestProperty("Authorization", auth);
+      }
+
+      connection.setRequestProperty("Range", "bytes=" + initialSize + "-");
+      connection.setConnectTimeout(5000);
+      setDownloaded(0);
+
+      // Connect
+      connection.connect();
+      int resp = connection.getResponseCode();
+      if (resp < 200 || resp >= 300)
+        throw new IOException(
+            "Recevied invalid http status code from server: " + resp);
+
+      // Check for valid content length.
+      long len = connection.getContentLength();
+      if (len >= 0)
+        setDownloadSize(len);
+      setStatus(Status.DOWNLOADING);
+
+      synchronized (this) {
+        stream = connection.getInputStream();
+      }
+      byte buffer[] = new byte[10240];
+      while (status == Status.DOWNLOADING) {
+        int read = stream.read(buffer);
+        if (read == -1)
+          break;
+
+        file.write(buffer, 0, read);
+        setDownloaded(getDownloaded() + read);
+
+        if (Thread.interrupted())
+          throw new InterruptedException();
+      }
+
+      if (getDownloadSize() != null) {
+        if (getDownloaded() < getDownloadSize())
+          throw new Exception("Incomplete download");
+      }
+      setStatus(Status.COMPLETE);
+    } catch (InterruptedException e) {
+      setStatus(Status.CANCELLED);
+      // lets InterruptedException go up to the caller
+      throw e;
+
+    } catch (SocketTimeoutException e) {
+      setStatus(Status.CONNECTION_TIMEOUT_ERROR);
+      setError(e);
+
+    } catch (Exception e) {
+      setStatus(Status.ERROR);
+      setError(e);
+
+    } finally {
+      if (file != null) {
+        try {
+          file.close();
+        } catch (Exception e) {
+        }
+      }
+
+      synchronized (this) {
+        if (stream != null) {
+          try {
+            stream.close();
+          } catch (Exception e) {
+          }
+        }
+      }
+    }
+  }
+
+  private void setError(Exception e) {
+    error = e;
+  }
+
+  public Exception getError() {
+    return error;
+  }
+
+  public boolean isCompleted() {
+    return status == Status.COMPLETE;
+  }
+}