Release Change Log


Date: 2024-02-23

  • #551 Resolves security issue that results in RCE. The fix breaks backwards compatibility for those that rely on the __array__ attribute used by numpy. This RCE is only exploitable when the server-side gets the attribute __array__ and calls it (e.g., np.array(x)). This issues effects all versions since major release 4.


Date: 2023-02-21

  • #527 Resolved timeout issue that was introduced in 5.2.1

  • #525 and #524 Fixed experimental thread binding struct for platforms where unsigned long is 8-bits

    • While the fix for thread binding is not backwards compatible, it only impacts people using an experimental feature. Hence, I did a patch version bump.


Date: 2022-11-25

  • #515 Support for Python 3.11 is available after teleportation bug fix

  • #507 Experimental support for threading is added (default is disabled for now)

  • #516 Resolved server-side exceptions due to the logic for checking if a name is in ModuleNamespace

  • #511 Improved documentation on the life-cycle of a netref/proxy-object


Date: 2022-08-03

  • #503 and can now be resolved without the suffix as well.


Date: 2022-07-30

  • #494 Added support for using decorators to expose methods (see #292)

  • #499 Allow BgServingThread serve and sleep intervals to be customized

  • #498 Avoid redefining hasattr_static on every _check_attr call

  • #489 Updated SSL context usage to avoid deprecated aspects and changes

  • #485 Add a configurable timeout on the zero deploy close method

  • #484 Fixed –mode CLI argument for rpyc_registry

  • #479 Fixed propagation of AttributeErrors raised by exposed descriptors

  • #476 Allow filtering by host on list_services

  • #493 and #502 Improved documentation and fixed typos

  • #492 Some work around race conditions but proper fix is rather involved (see #491)

  • 5.2.0 was skipped due to PyPi not allowing file name reuse


Date: 2022-02-26

  • Add types.MappingProxyType to _builtin_types #470

  • Updated documentation #469

  • Fixed spradic dealock issues from wait within AsyncResult #463 and #455

  • Fixed chained Classic RPyC connections #460

  • Added ability to list Registry services #452

  • Fixed bug that prevented RPyC from running on systems without SSL #451

  • Fixed unexpected behavior with respect to auto_register #445

  • Fixed propagation of chunk_size parameter for download_dir #433


Date: 1.11.2021

  • Fixed unexpected behavior when using inspect.isfunction #426

  • Now prevents installation of RPyC on unsupported versions of python #429


Date: 12.26.2020

Backwards Incompatible

  • RPyC 5.0.0 cannot teleport functions to earlier versions

  • Deprecated Python 2 support to coincide with it’s EOL


  • Server hostname default supports IPv4 and IPv6 by using the wildcard address #425

  • Added docker/docker-compose.yml for Python 3.6, 3.7, 3.8, 3.9, and 3.10 containers to improve local workflow

  • Fixed pickle failure on windows for connect_multiprocess and connect_thread #412

  • Fixed teleport function behavior for keyword-only arguments with default #422

  • Improved documentation on custom exception handling

  • Fixed IPv6 support for server #407

  • Added a simple asynchronous service example #400


Date: 4.25.2020

  • Fixed mutable object used as kwarg for Server ctor #376

  • Corrections to teleport example #374

  • Lowered GIL-lock acquires for <64kb within channel sends to address slowness #280


Date: 1.30.2020

  • Merged 3.7 and 3.8 teleportatio compat enhancement #371

  • Fixed connection hanging due to namepack cursor #369

  • Fixed test dependencies and is_py_* for 3.9


Date: 1.25.2020

  • Performance improvements: #366 and #351

  • Merged fix for propagate_KeyboardInterrupt_locally #364

  • Fixed handling of exceptions for request callbacks #365

  • Partially fixed return value for netref.__class__ #355


Date: 10.03.2019

  • Fixed CVE-2019-16328 which was caused by a missing protocol security check

  • Fixed RPyC over RPyC for mutable parameters and extended unit testing for #346


Date: 07.27.2019

  • Fixed netref.class_factory id_pack usage per #339 and added test cases

  • Name pack casted in _unbox to fix IronPython bug. Fixed #337

  • Increased chunk size to improve multi-client response time and throughput of large data #329

  • Added warning to _remote_tb when the major version of local and remote mismatch (#332)

  • OneShotServer termination was fixed by WilliamBruneau (#343)

  • Known issue with 3.8 for CodeType parameters (may drop Python2 support first)


Date: 05.25.2019

  • Added connection back-off and attempts for congested workloads

  • Fixed minor resource leak for ForkingServer (#304)

  • Cross-connection instance check for cached netref classes (#316)

  • Hashing fixed (#324)

  • New ID Pack convention breaks compatibility between a client/server >= 4.10 with a client/server < 4.10


Date: 04.08.2018

  • fix default hostname for ipv6 in (#277)

  • fix ThreadPoolServer not working (#283)


Date: 12.06.2018

  • fix ValueError during install due to absolute PATH in SOURCES.txt (#276)


Date: 11.06.2018

This release brings a few minor backward incompatibilities, so be sure to read on before upgrading. However, fear not: the ones that are most likely relevant to you have a relatively simple migration path.

Backward Incompatibilities

  • classic.teleport_function now executes the function in the connection’s namespace by default. To get the old behaviour, use teleport_function(conn, func, conn.modules[func.__module__].__dict__) instead.

  • Changed signature of Service.on_connect and on_disconnect, adding the connection as argument.

  • Changed signature of Service.__init__, removing the connection argument

  • no longer store connection as self._conn. (allows services that serve multiple clients using the same service object, see #198).

  • SlaveService is now split into two asymmetric classes: SlaveService and MasterService. The slave exposes functionality to the master but can not anymore access remote objects on the master (#232, #248). If you were previously using SlaveService, you may experience problems when feeding the slave with netrefs to objects on the master. In this case, do any of the following:

    • use ClassicService (acts exactly like the old SlaveService)

    • use SlaveService with a config that allows attribute access etc

    • use rpyc.utils.deliver to feed copies rather than netrefs to the slave

  • RegistryServer.on_service_removed is once again called whenever a service instance is removed, making it symmetric to on_service_added (#238) This reverts PR #173 on issue #172.

  • Removed module rpyc.experimental.splitbrain. It’s too confusing and undocumented for me and I won’t be developing it, so better remove it altogether. (It’s still available in the splitbrain branch)

  • Removed module rpyc.experimental.retunnel. Seemingly unused anywhere, no documentation, no clue what this is about.

  • bin/ will bind to instead of by default

  • SlaveService no longer serves exposed attributes (i.e., it now uses allow_exposed_attrs=False)

  • Exposed attributes no longer hide plain attributes if one otherwise has the required permissions to access the plain attribute. (#165)

What else is new

  • teleported functions will now be defined by default in the globals dict

  • Can now explicitly specify globals for teleported functions

  • Can now use streams as context manager

  • keep a hard reference to connection in netrefs, may fix some EOFError issues, in particular on Jython related (#237)

  • handle synchronous and asynchronous requests uniformly

  • fix deadlock with connections talking to each other multithreadedly (#270)

  • handle timeouts cumulatively

  • fix possible performance bug in Win32PipeStream.poll (oversleeping)

  • use readthedocs theme for documentation (#269)

  • actually time out sync requests (#264)

  • clarify documentation concerning exceptions in (#265)

  • fix __hash__ for netrefs (#267, #268)

  • rename async module to async_ for py37 compatibility (#253)

  • fix deliver() from IronPython to CPython2 (#251)

  • fix brine string handling in py2 IronPython (#251)

  • add gevent Server. For now, this requires using gevent.monkey.patch_all() before importing for rpyc. Client connections can already be made without further changes to rpyc, just using gevent’s monkey patching. (#146)

  • add function rpyc.lib.spawn to spawn daemon threads

  • fix several bugs in bin/ that crashed this script on startup (#231)

  • fix problem with MongoDB, or more generally any remote objects that have a catch-all __getattr__ (#165)

  • fix bug when copying remote numpy arrays (#236)

  • added rpyc.utils.helpers.classpartial to bind arguments to services (#244)

  • can now pass services optionally as instance or class (could only pass as class, #244)

  • The service is now charged with setting up the connection, doing so in Service._connect. This allows using custom protocols by e.g. subclassing Connection. More discussions and related features in #239-#247.

  • service can now easily override protocol handlers, by updating conn._HANDLERS in _connect or on_connect. For example: conn._HANDLERS[HANDLE_GETATTR] = self._handle_getattr.

  • most protocol handlers (Connection._handle_XXX) now directly get the object rather than its ID as first argument. This makes overriding individual handlers feel much more high-level. And by the way it turns out that this fixes two long-standing issues (#137, #153)

  • fix bug with proxying context managers (#228)

  • expose server classes from rpyc top level module

  • fix logger issue on jython


Date: 07.08.2017

  • Fix refcount leakage when unboxing from cache (#196)

  • Fix TypeError when dispatching exceptions on py2 (unicode)

  • Respect rpyc_protocol_config for default Service getattr (#202)

  • Support unix domain sockets (#100, #208)

  • Use first accessible server in connect_by_service (#220)

  • Fix deadlock problem with logging (#207, #212)

  • Fix timeout problem for long commands (#169)


Date: 26.07.2017

  • Add missing endpoints config in ThreadPoolServer (#222)

  • Fix jython support (#156, #171)

  • Improve documentation (#158, #185, #189, #198 and more)


Date: 14.06.2017

  • Fix export_function on python 3.6


Date: 09.06.2017

  • Fix issue high-cpu polling (#191, #218)

  • Fix filename argument in logging (#197)

  • Improved log messages (#191, #204)

  • Drop support for python 3.2 and py 2.5


Date: 29.05.2017

Please excuse the briefity for this versions changelist.


  • RPyC integrates with plumbum; plumbum is required for some features, like and zero deploy, but the core of the library doesn’t require it. It is, of course, advised to have it installed.

  • SshContext, SshTunnel classes killed in favor of plumbum’s SSH tunneling. The interface doesn’t change much, except that ssh_connect now accept a plumbum.SshMachine instance instead of SshContext.

  • Zero deploy: deploy RPyC to a remote machine over an SSH connection and form an SSH tunnel connected to it, in just one line of code. All you need is SSH access and a Python interpreter installed on the remote machine.

  • Dropping Python 2.4 support. RPyC now requires Python 2.5 - 3.3.

  • rpycd - a well-behaved daemon for, based on python-daemon

  • The OneShotServer is now exposed by rpyc_classic -m oneshot

  • scripts directory renamed bin

  • Introducing Splitbrain Python - running code on remote machines transparently. Although tested, it is still considered experimental.

  • Removing the BgServerThread and all polling/timeout hacks in favor of a “global background reactor thread” that handles all incoming transport from all connections. This should solve all threading issues once and for all.

  • Added MockClassicConnection - a mock RPyC “connection” that allows you to write code that runs either locally or remotely without modification

  • Added teleport_function


  • Fix (issue #76) for real this time

  • Fix issue with BgServingThread (#89)

  • Fix issue with ThreadPoolServer (#91)

  • Remove RPyC’s excepthook in favor of chaining the exception’s remote tracebacks in the exception class’ __str__ method. This solves numerous issues with logging and debugging.

  • Add OneShotServer

  • Add UNIX domain sockets (#100)


  • Windows: make SSH tunnels windowless (#68)

  • Fixes a compatibility issue with IronPython on Mono (#72)

  • Fixes an issue with introspection when an AttributeError is expected (#71)

  • The server now logs all exceptions (#73)

  • Forking server: call siginterrupt(False) in forked child (#76)

  • Shutting down the old wikidot site

  • Adding Travis CI integration


  • Adding missing import (#52)

  • Fixing site documentation issue (#54)

  • Fixing Python 3 incompatibilities (#58, #59, #60, #61, #66)

  • Fixing slice issue (#62)

  • Added the endpoints parameter to the config dict of connection (only on the server side)


  • Added support for IPv6 (#28)

  • Added SSH tunneling support (ssh_connect)

  • Added restricted object wrapping

  • Several fixes to AsyncResult and weak references

  • Added the ThreadPoolServer

  • Fixed some minor (harmless) races that caused tracebacks occasionally when server-threads terminated

  • Fixes issues #8, #41, #42, #43, #46, and #49.

  • Converted all CRLF to LF (#40)

  • Dropped TLSlite integration (#45). We’ve been dragging this corpse for too long.

  • New documentation (both the website and docstrings) written in Sphinx

    • The site has moved to sourceforge. Wikidot had served us well over the past three years, but they began displaying way too many ads and didn’t support uploading files over rsync, which made my life hard.

    • New docs are part of the git repository. Updating the site is as easy as make upload

  • Python 3.0-3.2 support


What’s New

  • Supports CPython 2.4-2.7, IronPython, and Jython

  • tlslite has been ported to python 2.5-2.7 (the original library targeted 2.3 and 2.4)

  • Initial python 3 support – not finished!

  • Moves to a more conventional directory structure

  • Moves to more standard facilities (logging, nosetests)

  • Solves a major performance issue with the BgServingThread (#32), by removing the contention between the two threads that share the connection

  • Fixes lots of issues concerning the ForkingServer (#3, #7, and #15)

  • Many small bug fixes (#16, #13, #4, etc.)

  • Integrates with the built-in ssl module for SSL support

    • now takes several --ssl-xxx switches (see --help for more info)

  • Fixes typos, running pylint, etc.

Breakage from 3.0.7

  • Removing egg builds (we’re pure python, and eggs just messed up the build)

  • Package layout changed drastically, and some files were renamed

    • The servers/ directory was renamed scripts/

    • was renamed

    • They scripts now install to your python scripts directory (no longer part of the package), e.g. C:\python27\Scripts

  • now takes --register in order to register, instead of --dont-register, which was a silly choice.

  • classic.tls_connect, factory.tls_connect were renamed tlslite_connect, to distinguish it from the new ssl_connect.


  • Moving to git as source control

  • Build script: more egg formats; register in pypi ; remove svn; auto-generate as well

  • Cosmetic touches to Connection: separate serve into _recv and dispatch

  • Shutdown socket before closing (SHUT_RDWR) to prevent TIME_WAIT and other problems with various Unixes

  • PipeStream: use low-level file APIs (, os.write) to prevent stdio-level buffering that messed up select

  • open logfile for writing (was opened for reading)

  • type of timeout is now int (was str)

  • utils/ better handling of sockets; fix python 2.4 syntax issue

  • ForkingServer: re-register SIGCHLD handler after handling that signal, to support non-BSD-compliant platforms where after the invocation of the signal handler, the handler is reset


  • Handle metaclasses better in inspect_methods

  • handle old-style-class exceptions better; python 2.4 issues

  • VdbAuthenticator: when loading files, open for read only; API changes (from_dict instead of from_users), from_file accepts open-mode

  • ForkingServer: better handling of SIGCHLD


  • now also creates egg files

  • Slightly improved servers/

  • Fixes to utis/

    • The authenticator is now invoked by _accept_client, which means it is invoked on the client’s context (thread or child process). This solves a problem with the forking server having a TLS authenticator.

    • Changed the forking server to handle SIGCHLD instead of using double-fork.


  • Fix: inspect_methods used dir and getattr to inspect the given object; this caused a problem with premature activation of properties (as they are activated by getattr). Now it inspects the object’s type instead, following the MRO by itself, to avoid possible side effects.


  • Changed versioning scheme: now 3.0.3 instead of 3.03, and the version tuple is (3, 0, 3)

  • Added servers/ - a utility to manage verifier databases (used by tlslite)

  • Added the --vdb switch to, which invokes a secure server (TLS) with the given VDB file.


  • Authenticators: authenticated servers now store the credentials of the connection in conn._config.credentials

  • Registry: added UDP and TCP registry servers and clients (from rpyc.utils.registry import ...)

  • Minor bug fixes

  • More tests

  • The test-suite now runs under python 2.4 too


  • Fixes some minor issues/bugs

  • The registry server can now be instantiated (no longer a singleton) and customized, and RPyC server can be customized to use the different registry.


Known Issues

  • comparison - comparing remote and local objects will usually not work, but there’s nothing to do about it.

  • 64bit platforms: since channels use 32bit length field, you can’t pass data/strings over 4gb. this is not a real limitation (unless you have a super-fast local network and tons of RAM), but as 64bit python becomes the defacto standard, I will upgrade channels to 64bit length field.

  • threads - in face of no better solution, and after consulting many people, I resorted to setting a timeout on the underlying recv(). This is not an elegant way, but all other solution required rewriting all sorts of threading primitives and were not necessarily deadlock/race-free. as the zen says, “practicality beats purity”.

  • Windows - pipes supported, but Win32 pipes work like shit

3.00 RC2

Known Issues

  • Windows - pipe server doesn’t work