diff --git a/.github/workflows/presubmit.yml b/.github/workflows/presubmit.yml
index 61376b39..1dc4a003 100644
--- a/.github/workflows/presubmit.yml
+++ b/.github/workflows/presubmit.yml
@@ -30,7 +30,7 @@ jobs:
             compiler: g++
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: sudo apt update; sudo apt install -y ${{ matrix.compiler }} ruby-dev libgsl-dev python3-dev valgrind
         if: ${{ matrix.os == 'ubuntu-latest' }}
       - run: brew install gsl automake libtool
@@ -39,7 +39,7 @@ jobs:
         with:
           python-version: '3.11'
         if: ${{ matrix.os == 'macos-latest' }}
-      - run: gem install --user-install rake ffi ffi-value whittle
+      - run: gem install --user-install rake ffi ffi-value whittle xmlrpc
       - run: pip3 install --user parglare
       - run: ./autogen.sh
       - run: mkdir -p build
@@ -55,7 +55,7 @@ jobs:
       - run: make -j check-valgrind-helgrind
         working-directory: build
         if: ${{ matrix.os == 'ubuntu-latest' }}
-      - uses: actions/upload-artifact@v2
+      - uses: actions/upload-artifact@v4
         if: failure()
         with:
           name: build-and-check
@@ -82,7 +82,7 @@ jobs:
         with:
           python-version: '3.11'
         if: ${{ matrix.os == 'macos-latest' }}
-      - run: gem install --user-install rake ffi ffi-value whittle
+      - run: gem install --user-install rake ffi ffi-value whittle xmlrpc
       - run: pip3 install --user parglare
       - run: ./autogen.sh
       - run: mkdir -p build
@@ -110,7 +110,7 @@ jobs:
         with:
           python-version: '3.11'
         if: ${{ matrix.os == 'macos-latest' }}
-      - run: gem install --user-install rake ffi ffi-value whittle
+      - run: gem install --user-install rake ffi ffi-value whittle xmlrpc
       - run: pip3 install --user parglare
       - run: ./autogen.sh
       - run: mkdir -p build
diff --git a/bindings/python/Makefile.am b/bindings/python/Makefile.am
index 11d69202..9fc75576 100644
--- a/bindings/python/Makefile.am
+++ b/bindings/python/Makefile.am
@@ -39,6 +39,7 @@ EXTRA_DIST = \
 	test/test_objective_space.py \
 	test/test_configuration_space.py \
 	test/test_feature_space.py \
+	test/tuner_server.py \
 	setup.py
 
 if ISMACOS
diff --git a/bindings/python/cconfigspace/base.py b/bindings/python/cconfigspace/base.py
index c8709657..640b9a0d 100644
--- a/bindings/python/cconfigspace/base.py
+++ b/bindings/python/cconfigspace/base.py
@@ -561,40 +561,40 @@ def deserialize(cls, format = 'binary', handle_map = None, map_handles = False,
     if format != 'binary':
       raise Error(Result(Result.ERROR_INVALID_VALUE))
     mode_count = 0;
-    if path:
+    if path is not None:
       mode_count += 1
-    if buffer:
+    if buffer is not None:
       mode_count += 1
-    if file_descriptor:
+    if file_descriptor is not None:
       mode_count += 1
     if not mode_count == 1:
       raise Error(Result(Result.ERROR_INVALID_VALUE))
-    if map_handles and not handle_map:
+    if map_handles and handle_map is None:
       raise Error(Result(Result.ERROR_INVALID_VALUE))
     o = ccs_object(0)
     options = [DeserializeOption.END]
     if map_handles:
       options = [DeserializeOption.MAP_HANDLES] + options
-    if handle_map:
+    if handle_map is not None:
       options = [DeserializeOption.HANDLE_MAP, handle_map.handle] + options
-    if vector_callback:
+    if vector_callback is not None:
       vector_cb_wrapper = _get_deserialize_vector_callback_wrapper(vector_callback)
       vector_cb_wrapper_func = ccs_object_deserialize_vector_callback_type(vector_cb_wrapper)
       options = [DeserializeOption.VECTOR_CALLBACK, vector_cb_wrapper_func, ct.py_object()] + options
-    if callback:
+    if callback is not None:
       cb_wrapper = _get_deserialize_data_callback_wrapper(callback)
       cb_wrapper_func = ccs_object_deserialize_data_callback_type(cb_wrapper)
       options = [DeserializeOption.DATA_CALLBACK, cb_wrapper_func, ct.py_object()] + options
-    elif _default_user_data_deserializer:
+    elif _default_user_data_deserializer is not None:
       options = [DeserializeOption.DATA_CALLBACK, _default_user_data_deserializer, ct.py_object()] + options
-    if buffer:
+    if buffer is not None:
       s = ct.c_size_t(ct.sizeof(buffer))
       res = ccs_object_deserialize(ct.byref(o), SerializeFormat.BINARY, SerializeOperation.MEMORY, s, buffer, *options)
-    elif path:
+    elif path is not None:
       p = str.encode(path)
       pp = ct.c_char_p(p)
       res = ccs_object_deserialize(ct.byref(o), SerializeFormat.BINARY, SerializeOperation.FILE, pp, *options)
-    elif file_descriptor:
+    elif file_descriptor is not None:
       fd = ct.c_int(file_descriptor)
       res = ccs_object_deserialize(ct.byref(o), SerializeFormat.BINARY, SerializeOperation.FILE_DESCRIPTOR, fd, *options)
     else:
diff --git a/bindings/python/cconfigspace/map.py b/bindings/python/cconfigspace/map.py
index e0bb6556..941b88b7 100644
--- a/bindings/python/cconfigspace/map.py
+++ b/bindings/python/cconfigspace/map.py
@@ -21,6 +21,10 @@ def __init__(self, handle = None, retain = False, auto_release = True):
     else:
       super().__init__(handle = handle, retain = retain, auto_release = auto_release)
 
+  @classmethod
+  def from_handle(cls, handle, retain = True, auto_release = True):
+    return cls(handle = handle, retain = retain, auto_release = auto_release)
+
   def __len__(self):
     v = ct.c_size_t()
     res = ccs_map_get_keys(self.handle, 0, None, ct.byref(v))
@@ -73,3 +77,12 @@ def values(self):
     res = ccs_map_get_values(self.handle, sz, v, None)
     Error.check(res)
     return [x.value for x in v]
+
+  def pairs(self):
+    sz = self.__len__()
+    if sz == 0:
+      return []
+    v = (Datum * sz)()
+    k = (Datum * sz)()
+    res = ccs_map_get_pairs(self.handle, sz, k, v, None)
+    return [(k[i].value, v[i].value) for i in range(sz)]
diff --git a/bindings/python/test/test_tuner.py b/bindings/python/test/test_tuner.py
index f65ae2e1..c617362b 100644
--- a/bindings/python/test/test_tuner.py
+++ b/bindings/python/test/test_tuner.py
@@ -1,6 +1,13 @@
 import unittest
 import sys
 import os as _os
+import signal
+import threading
+import subprocess
+import datetime
+import base64
+import xmlrpc.client
+import ctypes as ct
 from random import choice
 sys.path.insert(1, '.')
 sys.path.insert(1, '..')
@@ -167,6 +174,111 @@ def get_vector_data(otype, name):
     self.assertTrue(t_copy.suggest() in [x.configuration for x in optims_2])
     _os.remove('tuner.ccs')
 
+  class ServerThread(threading.Thread):
+    def __init__(self):
+      self.p = None
+      threading.Thread.__init__(self)
+
+    def run(self):
+      subprocess.run(['python3', _os.path.join(_os.path.abspath(_os.path.dirname(__file__)), 'tuner_server.py')], stdout = subprocess.DEVNULL, stderr = subprocess.DEVNULL)
+
+  class TunerProxy:
+    def __init__(self, name = "", objective_space = None):
+      self.server = xmlrpc.client.ServerProxy("http://localhost:8000/")
+      connected = False
+      start = datetime.datetime.now()
+      while not connected:
+        try:
+          connected = self.server.connected()
+        except Exception as err:
+          if datetime.datetime.now() - start > datetime.timedelta(seconds = 10):
+            raise
+      if objective_space is not None:
+        self.objective_space = objective_space
+        buff = objective_space.serialize()
+        self.id, result = self.server.create(name, base64.b64encode(buff))
+        map_str = base64.b64decode(result.data)
+        self.handle_map = ccs.deserialize(buffer = ct.create_string_buffer(map_str, len(map_str)))
+      else:
+        self.id, result = self.server.load(name)
+        self.handle_map = ccs.Map()
+        os_string = base64.b64decode(result.data)
+        self.objective_space = ccs.deserialize(buffer = ct.create_string_buffer(os_string, len(os_string)), handle_map = self.handle_map, map_handles = True)
+        rev_map = ccs.Map()
+        for (k, v) in self.handle_map.pairs():
+          if isinstance(v, ccs.Context) or isinstance(v, ccs.TreeSpace):
+            rev_map[ccs.Object(v.handle, retain = False, auto_release = False)] = k
+        buff = rev_map.serialize()
+        self.server.set_handle_map(self.id, base64.b64encode(buff))
+
+    def ask(self, count = 1):
+      buffs = [base64.b64decode(conf_str.data) for conf_str in self.server.ask(self.id, count)]
+      return [ccs.deserialize(buffer = ct.create_string_buffer(buff, len(buff)), handle_map = self.handle_map) for buff in buffs]
+
+    def tell(self, evals = []):
+      self.server.tell(self.id, [base64.b64encode(e.serialize()) for e in evals])
+      return self
+
+    def history(self):
+      buffs = [base64.b64decode(eval_str.data) for eval_str in self.server.history(self.id)]
+      return [ccs.deserialize(buffer = ct.create_string_buffer(buff, len(buff)), handle_map = self.handle_map) for buff in buffs]
+
+    def history_size(self):
+      return self.server.history_size(self.id)
+
+    def optima(self):
+      buffs = [base64.b64decode(eval_str.data) for eval_str in self.server.optima(self.id)]
+      return [ccs.deserialize(buffer = ct.create_string_buffer(buff, len(buff)), handle_map = self.handle_map) for buff in buffs]
+
+    def num_optima(self):
+      return self.server.num_optima(self.id)
+
+    def suggest(self):
+      buff = base64.b64decode(self.server.suggest(self.id).data)
+      return ccs.deserialize(buffer = ct.create_string_buffer(buff, len(buff)), handle_map = self.handle_map)
+
+    def save(self):
+      return self.server.save(self.id)
+
+    def kill(self):
+      return self.server.kill()
+
+  def test_server(self):
+    try:
+      thr = self.ServerThread()
+      thr.start()
+
+      os = self.create_tuning_problem()
+      t = self.TunerProxy(name = 'my_tuner', objective_space = os)
+      func = lambda x, y, z: [(x-2)*(x-2), sin(z+y)]
+      evals = [ccs.Evaluation(objective_space = os, configuration = c, values = func(*(c.values))) for c in t.ask(100)]
+      t.tell(evals)
+      hist = t.history()
+      self.assertEqual(100, len(hist))
+      evals = [ccs.Evaluation(objective_space = os, configuration = c, values = func(*(c.values))) for c in t.ask(100)]
+      t.tell(evals)
+      self.assertEqual(200, t.history_size())
+      optims = t.optima()
+      objs = [x.objective_values for x in optims]
+      objs.sort(key = lambda x: x[0])
+      # assert pareto front
+      self.assertTrue(all(objs[i][1] >= objs[i+1][1] for i in range(len(objs)-1)))
+      self.assertTrue(t.suggest() in [x.configuration for x in optims])
+
+      t.save()
+      t_copy = self.TunerProxy(name = "my_tuner")
+      hist = t_copy.history()
+      self.assertEqual(200, len(hist))
+      optims_2 = t_copy.optima()
+      self.assertEqual(len(optims), len(optims_2))
+      objs = [x.objective_values for x in optims_2]
+      objs.sort(key = lambda x: x[0])
+      self.assertTrue(all(objs[i][1] >= objs[i+1][1] for i in range(len(objs)-1)))
+      self.assertTrue(t_copy.suggest() in [x.configuration for x in optims_2])
+
+    finally:
+      self.assertTrue(t.kill())
+      thr.join()
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/bindings/python/test/tuner_server.py b/bindings/python/test/tuner_server.py
new file mode 100644
index 00000000..03d47e28
--- /dev/null
+++ b/bindings/python/test/tuner_server.py
@@ -0,0 +1,203 @@
+from xmlrpc.server import SimpleXMLRPCServer
+from threading import Lock
+from dataclasses import dataclass
+import sys
+import traceback
+import base64
+import ctypes as ct
+from random import choice
+sys.path.insert(1, '.')
+sys.path.insert(1, '..')
+import cconfigspace as ccs
+
+class TunerData:
+  def __init__(self):
+    self.history = []
+    self.optima = []
+
+def deletef(tuner):
+  return None
+
+def askf(tuner, features, count):
+  if count is None:
+    return (None, 1)
+  else:
+    cs = tuner.search_space
+    return (cs.samples(count), count)
+
+def tellf(tuner, evaluations):
+  tuner.tuner_data.history += evaluations
+  for e in evaluations:
+    discard = False
+    new_optima = []
+    for o in tuner.tuner_data.optima:
+      if discard:
+        new_optima.append(o)
+      else:
+        c = e.compare(o)
+        if c == ccs.Comparison.EQUIVALENT or c == ccs.Comparison.WORSE:
+          discard = True
+          new_optima.append(o)
+        elif c == ccs.Comparison.NOT_COMPARABLE:
+          new_optima.append(o)
+    if not discard:
+      new_optima.append(e)
+    tuner.tuner_data.optima = new_optima
+  return None
+
+def get_historyf(tuner, features):
+  return tuner.tuner_data.history
+
+def get_optimaf(tuner, features):
+  return tuner.tuner_data.optima
+
+def suggestf(tuner, features):
+  if not tuner.tuner_data.optima:
+    return ask(tuner, 1)
+  else:
+    return choice(tuner.tuner_data.optima).configuration
+
+def get_vector_data(otype, name):
+  return (ccs.UserDefinedTuner.get_vector(delete = deletef, ask = askf, tell = tellf, get_optima = get_optimaf, get_history = get_historyf, suggest = suggestf), TunerData())
+
+@dataclass
+class TunerStruct:
+  tuner: list
+  handle_map: ccs.Map = None
+
+class MyServer(SimpleXMLRPCServer):
+  def serve_forever(self):
+    self.quit = 0
+    while not self.quit:
+      self.handle_request()
+
+s = MyServer(('localhost', 8000))
+s.register_introspection_functions()
+
+@s.register_function
+def connected():
+  return True
+
+count = 0
+tuners = dict()
+tuners_store = dict()
+mutex = Lock()
+
+@s.register_function
+def create(name, os_string):
+  global count
+  handle_map = ccs.Map()
+  os_string = base64.b64decode(os_string.data)
+  os = ccs.deserialize(buffer = ct.create_string_buffer(os_string, len(os_string)), handle_map = handle_map, map_handles = True)
+  t = ccs.UserDefinedTuner(name = name, objective_space = os, delete = deletef, ask = askf, tell = tellf, get_optima = get_optimaf, get_history = get_historyf, suggest = suggestf, tuner_data = TunerData())
+
+  rev_map = ccs.Map()
+  for (k, v) in handle_map.pairs():
+    if isinstance(v, ccs.Context) or isinstance(v, ccs.TreeSpace):
+      rev_map[ccs.Object(v.handle, retain = False, auto_release = False)] = k
+  buff = rev_map.serialize()
+  tstruct = TunerStruct(t, handle_map)
+  ident = None
+  with mutex:
+    ident = count
+    count += 1
+    tuners[ident] = tstruct
+  return (ident, base64.b64encode(buff))
+
+@s.register_function
+def ask(ident, count):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  return [base64.b64encode(c.serialize()) for c in tstruct.tuner.ask(count)]
+
+@s.register_function
+def tell(ident, evals):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  evals = [base64.b64decode(e.data) for e in evals]
+  evals = [ccs.deserialize(buffer = ct.create_string_buffer(e, len(e)), handle_map = tstruct.handle_map) for e in evals]
+  tstruct.tuner.tell(evals)
+  return True
+
+@s.register_function
+def history(ident):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  buffers = [e.serialize() for e in tstruct.tuner.history()]
+  return [base64.b64encode(buff) for buff in buffers]
+
+@s.register_function
+def history_size(ident):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  return tstruct.tuner.history_size()
+
+@s.register_function
+def optima(ident):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  buffers = [e.serialize() for e in tstruct.tuner.optima()]
+  return [base64.b64encode(buff) for buff in buffers]
+
+@s.register_function
+def num_optima(ident):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  return tstruct.tuner.num_optima()
+
+@s.register_function
+def suggest(ident):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  e = tstruct.tuner.suggest()
+  buff = e.serialize()
+  return base64.b64encode(buff)
+
+@s.register_function
+def save(ident):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  buff = tstruct.tuner.serialize()
+  with mutex:
+    tuners_store[tstruct.tuner.name] = buff
+  return True
+
+@s.register_function
+def load(name):
+  global count
+  buff = None
+  with mutex:
+    buff = tuners_store[name]
+  t = ccs.deserialize(buffer = buff, vector_callback = get_vector_data)
+  tstruct = TunerStruct(t)
+  ident = None
+  with mutex:
+    ident = count
+    count += 1
+    tuners[ident] = tstruct
+  buff = t.objective_space.serialize()
+  return (ident, base64.b64encode(buff))
+
+@s.register_function
+def set_handle_map(ident, map_str):
+  tstruct = None
+  with mutex:
+    tstruct = tuners[ident]
+  map_str = base64.b64decode(map_str.data)
+  tstruct.handle_map = ccs.deserialize(buffer = ct.create_string_buffer(map_str, len(map_str)))
+  return True
+
+@s.register_function
+def kill():
+  s.quit = 1
+  return True
+
+s.serve_forever()
diff --git a/bindings/ruby/Makefile.am b/bindings/ruby/Makefile.am
index 79586395..db69d249 100644
--- a/bindings/ruby/Makefile.am
+++ b/bindings/ruby/Makefile.am
@@ -40,6 +40,7 @@ EXTRA_DIST = \
 	test/test_configuration_space.rb \
 	test/test_distribution.rb \
 	test/test_evaluation.rb \
+	test/tuner_server.rb \
 	rakefile \
 	cconfigspace.gemspec \
 	LICENSE
diff --git a/bindings/ruby/test/test_tuner.rb b/bindings/ruby/test/test_tuner.rb
index 961cfbb3..b43562b4 100644
--- a/bindings/ruby/test/test_tuner.rb
+++ b/bindings/ruby/test/test_tuner.rb
@@ -170,5 +170,130 @@ def test_user_defined
     assert( t_copy.optima.collect(&:configuration).include?(t_copy.suggest) )
     File.delete('tuner.ccs')
   end
+
+  require 'open3'
+  require 'xmlrpc/client'
+  require 'base64'
+  class TunerProxy
+    attr_reader :server
+    attr_reader :id
+    attr_reader :handle_map
+    attr_reader :objective_space
+    def initialize(name: "", objective_space: nil)
+      @server = XMLRPC::Client.new2('http://localhost:8080/RPC2')
+      connected = false
+      start = Time.now
+      while !connected
+        begin
+          connected = server.call('connected')
+        rescue
+          raise if Time.now - start > 10
+        end
+      end
+      if objective_space
+        @objective_space = objective_space
+        buff = objective_space.serialize
+        str = Base64.encode64(buff.get_bytes(0, buff.size))
+        @id, result = server.call('tuner.create', name, str)
+        @handle_map = CCS.deserialize(buffer: FFI::MemoryPointer.from_string(Base64.decode64(result)))
+      else
+        @id, result = server.call('tuner.load', name)
+        @handle_map = CCS::Map.new
+        @objective_space = CCS.deserialize(buffer: FFI::MemoryPointer.from_string(Base64.decode64(result)), handle_map: @handle_map, map_handles: true)
+        map = CCS::Map.new
+        @handle_map.pairs.select { |_ , v|
+          v.is_a?(CCS::Context) || v.is_a?(CCS::TreeSpace)
+        }.each { |k, v|
+          map[CCS::Object::new(v.handle, retain: false, auto_release: false)] = k
+        }
+        buff = map.serialize
+        server.call('tuner.set_handle_map', @id, Base64.encode64(buff.get_bytes(0, buff.size)))
+      end
+    end
+
+    def ask(count = 1)
+      server.call('tuner.ask', @id, count).collect { |c|
+        CCS.deserialize(buffer: FFI::MemoryPointer.from_string(Base64.decode64(c)), handle_map: @handle_map)
+      }
+    end
+
+    def tell(evals = [])
+      evals_serialized = evals.collect { |e| e.serialize }.collect { |buff| Base64.encode64(buff.get_bytes(0, buff.size)) }
+      server.call('tuner.tell', @id, evals_serialized)
+      self
+    end
+
+    def history
+      server.call('tuner.history', @id).collect { |e|
+        CCS.deserialize(buffer: FFI::MemoryPointer.from_string(Base64.decode64(e)), handle_map: @handle_map)
+      }
+    end
+
+    def history_size
+      server.call('tuner.history_size', @id)
+    end
+
+    def optima
+      server.call('tuner.optima', @id).collect { |e|
+        CCS.deserialize(buffer: FFI::MemoryPointer.from_string(Base64.decode64(e)), handle_map: @handle_map)
+      }
+    end
+
+    def num_optima
+      server.call('tuner.num_optima', @id)
+    end
+
+    def suggest
+      e = server.call('tuner.suggest', @id)
+      CCS.deserialize(buffer: FFI::MemoryPointer.from_string(Base64.decode64(e)), handle_map: @handle_map)
+    end
+
+    def save
+      server.call('tuner.save', @id)
+    end
+  end
+
+  def test_server
+    begin
+      pid = nil
+      thr = Thread.new do
+        Open3.popen2e(RbConfig.ruby, File.join(File.dirname(__FILE__), 'tuner_server.rb')) { |stdin, stdout_stderr, wait_thr|
+          pid = wait_thr.pid
+          stdout_stderr.read
+        }
+      end
+      os = create_tuning_problem
+      t = TunerProxy.new(name: "my_tuner", objective_space: os)
+      func = lambda { |(x, y, z)|
+        [(x-2)**2, Math.sin(z+y)]
+      }
+      evals = t.ask(100).collect { |c|
+        CCS::Evaluation::new(objective_space: os, configuration: c, values: func[c.values])
+      }
+      t.tell evals
+      hist = t.history
+      assert_equal(100, hist.size)
+      evals = t.ask(100).collect { |c|
+        CCS::Evaluation::new(objective_space: os, configuration: c, values: func[c.values])
+      }
+      t.tell evals
+      assert_equal(200, t.history_size)
+      objs = t.optima.collect(&:objective_values).sort
+      objs.collect { |(_, v)| v }.each_cons(2) { |v1, v2| assert( (v1 <=> v2) > 0 ) }
+      assert( t.optima.collect(&:configuration).include?(t.suggest) )
+
+      t.save
+      t_copy = TunerProxy.new(name: "my_tuner")
+      hist = t_copy.history
+      assert_equal(200, hist.size)
+      assert_equal(t.num_optima, t_copy.num_optima)
+      objs = t_copy.optima.collect(&:objective_values).sort
+      objs.collect { |(_, v)| v }.each_cons(2) { |v1, v2| assert( (v1 <=> v2) > 0 ) }
+      assert( t_copy.optima.collect(&:configuration).include?(t_copy.suggest) )
+    ensure
+      Process.kill("SIGHUP", pid)
+      thr.join
+    end
+  end
 end
 
diff --git a/bindings/ruby/test/tuner_server.rb b/bindings/ruby/test/tuner_server.rb
new file mode 100644
index 00000000..8d5e232f
--- /dev/null
+++ b/bindings/ruby/test/tuner_server.rb
@@ -0,0 +1,210 @@
+require_relative '../lib/cconfigspace'
+require 'xmlrpc/server'
+require 'base64'
+
+CCS.init
+
+class TunerData
+  attr_accessor :history, :optima
+  def initialize
+    @history = []
+    @optima = []
+  end
+end
+
+del = lambda { |tuner| nil }
+ask = lambda { |tuner, _, count|
+  if count
+    cs = tuner.search_space
+    [cs.samples(count), count]
+  else
+    [nil, 1]
+  end
+}
+tell = lambda { |tuner, evaluations|
+  tuner.tuner_data.history.concat(evaluations)
+  evaluations.each { |e|
+    discard = false
+    tuner.tuner_data.optima = tuner.tuner_data.optima.collect { |o|
+      unless discard
+        case e.compare(o)
+        when :CCS_COMPARISON_EQUIVALENT, :CCS_COMPARISON_WORSE
+          discard = true
+          o
+        when :CCS_COMPARISON_NOT_COMPARABLE
+          o
+        else
+          nil
+        end
+      else
+        o
+      end
+    }.compact
+    tuner.tuner_data.optima.push(e) unless discard
+  }
+}
+get_history = lambda { |tuner, _|
+  tuner.tuner_data.history
+}
+get_optima = lambda { |tuner, _|
+  tuner.tuner_data.optima
+}
+suggest = lambda { |tuner, _|
+  if tuner.tuner_data.optima.empty?
+    ask.call(tuner, 1)
+  else
+    tuner.tuner_data.optima.sample.configuration
+  end
+}
+get_vector_data = lambda { |otype, name|
+  [CCS::UserDefinedTuner.get_vector(del: del, ask: ask, tell: tell, get_optima: get_optima, get_history: get_history, suggest: suggest), TunerData.new]
+}
+
+s = XMLRPC::Server.new(8080)
+count = 0
+tuners = {}
+# Could be on disk
+tuners_store = {}
+mutex = Mutex.new
+
+TunerStruct = Struct.new(:tuner, :handle_map)
+
+s.add_handler('connected') do
+  true
+end
+
+s.add_handler('tuner.create') do |name, os_string|
+  handle_map = CCS::Map.new
+  os_string = Base64.decode64(os_string)
+  os = CCS.deserialize(buffer: FFI::MemoryPointer.from_string(os_string), handle_map: handle_map, map_handles: true)
+  t = CCS::UserDefinedTuner::new(name: name, objective_space: os, del: del, ask: ask, tell: tell, get_optima: get_optima, get_history: get_history, suggest: suggest, tuner_data: TunerData.new)
+
+  map = CCS::Map.new
+  handle_map.pairs.select { |_ , v|
+     v.is_a?(CCS::Context) || v.is_a?(CCS::TreeSpace)
+    }.each { |k, v|
+     map[CCS::Object::new(v.handle, retain: false, auto_release: false)] = k
+    }
+  buff = map.serialize
+  tstruct = TunerStruct.new(t, handle_map)
+  id = nil
+  mutex.synchronize {
+    id = count
+    count += 1
+    tuners[id] = tstruct
+  }
+  [id, Base64.encode64(buff.get_bytes(0, buff.size))]
+end
+
+s.add_handler('tuner.ask') do |id, count|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  tstruct.tuner.ask(count).collect { |c|
+    buff = c.serialize
+    Base64.encode64(buff.get_bytes(0, buff.size))
+  }
+end
+
+s.add_handler('tuner.tell') do |id, evals|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  evals.collect! { |e|
+    e = Base64.decode64(e)
+    CCS.deserialize(buffer: FFI::MemoryPointer.from_string(e), handle_map: tstruct.handle_map)
+  }
+  tstruct.tuner.tell evals
+  true
+end
+
+s.add_handler('tuner.history') do |id|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  tstruct.tuner.history.collect { |e|
+    buff = e.serialize
+    Base64.encode64(buff.get_bytes(0, buff.size))
+  }
+end
+
+s.add_handler('tuner.history_size') do |id|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  tstruct.tuner.history_size
+end
+
+s.add_handler('tuner.optima') do |id|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  tstruct.tuner.optima.collect { |e|
+    buff = e.serialize
+    Base64.encode64(buff.get_bytes(0, buff.size))
+  }
+end
+
+s.add_handler('tuner.num_optima') do |id|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  tstruct.tuner.num_optima
+end
+
+s.add_handler('tuner.suggest') do |id|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  e = tstruct.tuner.suggest
+  buff = e.serialize
+  Base64.encode64(buff.get_bytes(0, buff.size))
+end
+
+s.add_handler('tuner.save') do |id|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  buff = tstruct.tuner.serialize
+  mutex.synchronize {
+    tuners_store[tstruct.tuner.name] = buff
+  }
+  true
+end
+
+s.add_handler('tuner.load') do |name|
+  buff = nil
+  mutex.synchronize {
+    buff = tuners_store[name]
+  }
+  t = CCS.deserialize(buffer: buff, vector_callback: get_vector_data)
+  tstruct = TunerStruct.new(t, nil)
+  id = nil
+  mutex.synchronize {
+    id = count
+    count += 1
+    tuners[id] = tstruct
+  }
+  buff = t.objective_space.serialize
+  [id, Base64.encode64(buff.get_bytes(0, buff.size))]
+end
+
+s.add_handler('tuner.set_handle_map') do |id, map_str|
+  tstruct = nil
+  mutex.synchronize {
+    tstruct = tuners[id]
+  }
+  tstruct.handle_map = CCS.deserialize(buffer: FFI::MemoryPointer.from_string(Base64.decode64(map_str)))
+  true
+end
+
+s.serve
+