diff --git a/README.md b/README.md
index 0bf00ee..e9d16b7 100644
--- a/README.md
+++ b/README.md
@@ -43,6 +43,14 @@ apt-get install -y extpython-python3.6
 ```
 
 
+Replication
+-----------
+
+Repobot can automatically copy packages to neighbor repobot instances. Pass `-n` with one or more neighbor addresses in
+the format of `http://1.2.3.4:8080`. When new packages are submitted, they will be queued for replication. The server
+will periodically attempt to submit the package to each neighbor.
+
+
 Notes
 -----
 
diff --git a/repobot/provider.py b/repobot/provider.py
index 14ad1af..acdf7e3 100644
--- a/repobot/provider.py
+++ b/repobot/provider.py
@@ -5,6 +5,10 @@ from jinja2 import Environment, FileSystemLoader, select_autoescape
 import cherrypy
 
 
+class DuplicateException(Exception):
+    pass
+
+
 class PkgProvider(object):
     def __init__(self, db, repo, datadir):
         """
@@ -26,6 +30,12 @@ class PkgProvider(object):
         """
         raise NotImplementedError()
 
+    def get_path(self, pkgobj, fname):
+        """
+        Get the path to a package file in the repo
+        """
+        raise NotImplementedError()
+
 
 class PyPiProvider(PkgProvider):
     def add_package(self, pkgobj, fname, fobj, params):
@@ -33,7 +43,7 @@ class PyPiProvider(PkgProvider):
             pkgobj.data["files"] = plist()
 
         if fname in pkgobj.data["files"]:
-            raise Exception("File {} already in package {}-{}".format(fname, pkgobj.name, pkgobj.version))
+            raise DuplicateException("File {} already in package {}-{}".format(fname, pkgobj.name, pkgobj.version))
 
         pkgdir = os.path.join(self.dir, pkgobj.name)
         os.makedirs(pkgdir, exist_ok=True)
@@ -65,6 +75,10 @@ class PyPiProvider(PkgProvider):
             fpath = os.path.join(self.dir, args[0], args[1])
             return cherrypy.lib.static.serve_file(os.path.abspath(fpath), "application/octet-stream")
 
+    def get_path(self, pkgobj, fname):
+        assert fname in pkgobj.data["files"]
+        return os.path.join(self.dir, pkgobj.name, fname)
+
 
 from subprocess import check_call, check_output, Popen, PIPE
 from tempfile import NamedTemporaryFile, TemporaryDirectory
@@ -105,8 +119,7 @@ class AptProvider(PkgProvider):
         if "files" not in pkgobj.data:
             pkgobj.data["files"] = plist()
         if fname in pkgobj.data["files"]:
-            # raise Exception("File {} already in package {}-{}".format(fname, pkgobj.name, pkgobj.version))
-            pass
+            raise DuplicateException("File {} already in package {}-{}".format(fname, pkgobj.name, pkgobj.version))
 
         with AptlyConfig(self.dir) as conf:
             if not os.path.exists(os.path.join(self.dir, "db")):
@@ -194,6 +207,10 @@ Expire-Date: 0
     def _gpg_dir(self):
         return os.path.join(self.dir, "gpg")
 
+    def get_path(self, pkgobj, fname):
+        assert fname in pkgobj.data["files"]
+        return os.path.join(self.dir, "public", "pool", "main", pkgobj.name[0], pkgobj.name, fname)
+
 
 providers = {"pypi": PyPiProvider,
              "apt": AptProvider}
diff --git a/repobot/replication.py b/repobot/replication.py
new file mode 100644
index 0000000..f7f69b0
--- /dev/null
+++ b/repobot/replication.py
@@ -0,0 +1,76 @@
+from urllib.parse import urlparse, urlunsplit, urlencode
+from time import sleep
+from threading import Thread
+from repobot.provider import providers
+import logging
+import os
+from requests import post
+
+
+log = logging.getLogger("replication")
+
+
+class RepoReplicator(object):
+    def __init__(self, db, data_root, neighbors):
+        """
+        :param neighbors: list of replication neighbor uris like 'http://1.2.3.4:8080'
+        """
+        self.db = db
+        self.data_root = data_root
+        self.neighbors = [urlparse(i) for i in neighbors]
+        self.worker = None
+
+    def start(self):
+        if not self.neighbors:
+            return
+        self.worker = ReplicationWorker(self)
+        self.worker.start()
+
+
+class ReplicationWorker(Thread):
+    def __init__(self, master):
+        super().__init__()
+        self.daemon = True
+        self.master = master
+
+    def run(self):
+        while True:
+            with self.master.db.db.transaction() as c:
+                # for item in c.root.sendqueue:
+                log.info("items in queue: %s", len(c.root.sendqueue))
+                if len(c.root.sendqueue) > 0:
+                    item = c.root.sendqueue[0]
+                    if self.replicate(item):
+                        c.root.sendqueue.pop(0)
+                        log.info("Replication successful")
+            sleep(5)
+
+    def replicate(self, item):
+        item_type, item = item
+        if item_type == "package":
+            return self.replicate_package(item)
+
+    def replicate_package(self, item):
+        repo, pkg, fname, params = item
+        datadir = os.path.join(self.master.data_root, repo.provider, repo.name)
+        provider = providers[repo.provider](self.master.db, repo, datadir)
+        fpath = provider.get_path(pkg, fname)
+
+        for neighbor in self.master.neighbors:
+            q_params = {"provider": repo.provider,
+                        "reponame": repo.name,
+                        "name": pkg.name,
+                        "version": pkg.version}
+            q_params.update(**params)
+            url = urlunsplit(["http", neighbor.netloc, "/addpkg", urlencode(q_params), None])
+            with open(fpath, 'rb') as fitem:
+                try:
+                    r = post(url, files={'f': (fname, fitem)}, timeout=(10, 30))
+                    if r.status_code not in (200, 409):
+                        r.raise_for_status()
+                except Exception as e:
+                    log.warning("Failed replication of %s to %s: %s", pkg, neighbor.geturl(), str(e))
+                    return False
+            log.info("Replicated %s to %s", pkg, neighbor.geturl())
+
+        return True
diff --git a/repobot/repos.py b/repobot/repos.py
index 5d132fd..7694a32 100644
--- a/repobot/repos.py
+++ b/repobot/repos.py
@@ -28,6 +28,9 @@ class RepoPackage(persistent.Persistent):
         self.version = version
         self.data = pmap()
 
+    def __str__(self):
+        return "<RepoPackage {}@{}>".format(self.name, self.version)
+
 
 class RepoDb(object):
     def __init__(self, db_path, data_root):
@@ -38,13 +41,19 @@ class RepoDb(object):
         with self.db.transaction() as c:
             if "repos" not in c.root():
                 c.root.repos = BTrees.OOBTree.BTree()
+            if "sendqueue" not in c.root():
+                c.root.sendqueue = plist()
 
     def add_package(self, provider, reponame, pkgname, pkgversion, fname, fobj, params):
         with self.db.transaction() as c:
             repo = self._get_repo(c, provider, reponame)
             datadir = os.path.join(self.data_root, provider, reponame)
             provider = providers[repo.provider](self.db, repo, datadir)
-            provider.add_package(repo.get_package(pkgname, pkgversion), fname, fobj, params)
+            # Add the package
+            pkg = repo.get_package(pkgname, pkgversion)
+            provider.add_package(pkg, fname, fobj, params)
+            # Pack successfully added, queue the file for replication
+            c.root.sendqueue.append(("package", (repo, pkg, fname, params, )))
 
     def _get_repo(self, c, provider, name):
         if provider not in c.root.repos:
diff --git a/repobot/server.py b/repobot/server.py
index fe57a9c..95323fb 100644
--- a/repobot/server.py
+++ b/repobot/server.py
@@ -1,6 +1,8 @@
 import cherrypy
 import logging
 from repobot.repos import RepoDb
+from repobot.provider import DuplicateException
+from repobot.replication import RepoReplicator
 
 
 class AppWeb(object):
@@ -9,12 +11,27 @@ class AppWeb(object):
 
     @cherrypy.expose
     def addpkg(self, provider, reponame, name, version, f, **params):
-        self.db.add_package(provider, reponame, name, version, f.filename, f.file, params)
+        try:
+            self.db.add_package(provider, reponame, name, version, f.filename, f.file, params)
+        except DuplicateException:
+            raise cherrypy.HTTPError(409, 'Package already exists')
 
     @cherrypy.expose
     def repo(self, provider, repo, *args):
         return self.db.browse_repo(provider, repo, args)
 
+    @cherrypy.expose
+    def index(self):
+        yield "<pre>"
+        with self.db.db.transaction() as c:
+            for provider, repos in c.root.repos.items():
+                for reponame, repo in repos.items():
+                    print(repo)
+                    for pkgname, versions in repo.packages.items():
+                        for version, pkg in versions.items():
+                            for fname in pkg.data["files"]:
+                                yield "{}/{}/{}/{}/{}\n".format(provider, reponame, pkgname, version, fname)
+
 
 class FlatDispatch(cherrypy.dispatch.Dispatcher):
     def __init__(self, method):
@@ -38,6 +55,7 @@ def main():
     parser.add_argument('-p', '--port', default=8080, type=int, help="tcp port to listen on")
     parser.add_argument('-s', '--database', default="./repos.db", help="path to persistent database")
     parser.add_argument('-d', '--data-root', default="./data/", help="data storage dir")
+    parser.add_argument('-n', '--neighbors', nargs="+", default=[], help="Replication neighbor uris")
     parser.add_argument('--debug', action="store_true", help="enable development options")
 
     args = parser.parse_args()
@@ -46,6 +64,9 @@ def main():
                         format="%(asctime)-15s %(levelname)-8s %(filename)s:%(lineno)d %(message)s")
 
     db = RepoDb(args.database, args.data_root)
+    repl = RepoReplicator(db, args.data_root, args.neighbors)
+
+    repl.start()
 
     web = AppWeb(db)
 
diff --git a/requirements.txt b/requirements.txt
index 94d3249..00dd9fa 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,6 @@
 backports.functools-lru-cache==1.5
 BTrees==4.5.1
+certifi==2018.10.15
 chardet==3.0.4
 cheroot==6.5.2
 CherryPy==18.0.1
@@ -8,6 +9,7 @@ deb-pkg-tools==4.5
 executor==21.2
 fasteners==0.14.1
 humanfriendly==4.16.1
+idna==2.7
 jaraco.functools==1.20
 Jinja2==2.10
 MarkupSafe==1.0
@@ -19,9 +21,11 @@ property-manager==2.3.1
 python-debian==0.1.33
 python-memcached==1.59
 pytz==2018.5
+requests==2.20.0
 six==1.11.0
 tempora==1.13
 transaction==2.2.1
+urllib3==1.24
 verboselogs==1.7
 zc.lockfile==1.3.0
 ZConfig==3.3.0