Px 0.13.0

What's new in 0.13.0

Improvements
- Px now requires pymcurl 8.23.0.2 or newer, which provides the keepalive,
low-speed timeout, and auth-retry APIs used by Px.
- PAC dnsResolve() (and so isResolvable()/isInNet()) and IP-based
--noproxy matching use a cached, bounded DNS resolver: successful and
failed lookups are cached, concurrent lookups of one name are shared, and
slow resolvers no longer stall unrelated requests (#273).
- px --test now reports every connectivity check as passed or failed and
completes all checks before returning a failure status (#274).
- Release binaries and Docker images bundle the newest CPython 3.13 patch
available to the build tools (uv's python-build-standalone,
actions/setup-python, python.org's Windows embed zips, and the
python:3.13-alpine image), and log the bundled version (#275).
- Installation docs now cover uninstalling Px for winget, pip and standalone
binary installs, including removing the Windows auto-start entry first.
New features
- Switched to libuv-based event loops: winloop on Windows, uvloop on
Linux/macOS. These replace Python's default asyncio event loop with libuv,
providing significantly improved throughput for CONNECT tunnels and fixing
px randomly becoming unresponsive on Windows after network disruptions
(CPython bug #93821). Falls back to the default event loop gracefully if
the libuv library is not available (#268).
- New --event-loop=auto|asyncio option (PX_EVENT_LOOP, event_loop in
px.ini) to run on Python's default asyncio event loop instead of
winloop/uvloop.
- New --authretry=<seconds> option (PX_AUTHRETRY, authretry in
px.ini) takes a float number of seconds (fractions allowed) and lets Px
probe an upstream proxy again after it has been blocked for repeated 407s.
For example, --authretry=300 retries every 5 minutes. Once blocked, one
request is let through per interval and all other requests are refused until
that probe succeeds. A successful response unblocks the proxy immediately;
another 407 re-blocks it. Default 0 keeps blocked proxies blocked until
Kerberos ticket renewal or restart. Thanks to #276 (enkunkun) for identifying
the problem.
Bug fixes
- The macOS binary no longer links Homebrew's OpenSSL by absolute path, which
made SSL and pyspnego fail to load on Macs without that exact Homebrew
version. It is now built with a self-contained python-build-standalone
CPython. The release build scans every bundled Mach-O file and rejects …

Full release notes »