pypi / ipykernel

ipykernel

What changed in ipykernel 6 to 7, from its official release notes, upgrade guides and advisories. Sources checked 2026-11-07.

11 breaking2 security2 deprecations11 new APIs and options5 behavior and defaults13 fixes and other

See which of these apply to your code, ranked, in your agent:

npx @unstale/cli init

ipykernel 729 changes

The minimum supported Python version is now 3.11.
7.4.0release notes
The PUB socket was replaced with an XPUB socket.
7.2.0release notes
By default, thread output routes to the latest cell unless get_ipython().set_parent() is called explicitly; this behavior is now opt-in.
7.1.0release notes
Support for Python 3.9 is dropped.
7.0.0release notes

The debugger temporary directory is created with 0o700 permissions.
7.4.0release notes
Supports ZMQ Curve for transport encryption.
7.3.0release notes

Thread-local parent headers can now be set and reset.
7.4.0release notes
Adds register_hook to ZMQShellDisplayHook so developers can register display hooks.
7.3.0release notes
ZMQInteractiveShell supports the new iPython system_raise_on_error flag.
7.3.0release notes
Adds unregister_hook to ZMQShellDisplayHook so developers can unregister display hooks.
7.3.0release notes
The kernelspec now includes kernel_protocol_version, allowing the kernel protocol version to be specified there.
7.2.0release notes
Adds a traitlet to store display outputs in history for %notebook saves; it defaults to False.
6.31.0, 7.1.0release notes release notes
Adds experimental support for kernel subshells, implemented using Tornado event loops.
7.0.0release notes

Async cells can now process Comm messages.
7.4.0release notes
psutil is optional at runtime and its import is deferred until needed.
7.4.0release notes
Passes cell_meta from do_execute to run_cell.
7.3.0release notes
The kernel filters internal frames from callstacks.
7.2.0release notes
The kernel now advertises protocol 5.5.
7.2.0release notes

The debug handler now validates variable names.
7.4.0release notes
ProactorEventLoop is enabled for ipykernel on Windows.
7.4.0release notes
When a subshell is unknown, replies now follow the busy, error, idle sequence.
7.4.0release notes
supported_encryption now uses a list, matching the latest JEP state.
7.4.0release notes
Cell execution is marked as failing when a formatter errors out.
7.3.0release notes
The IOPubThread constructor is backward compatible, helping existing code continue to work.
7.2.0release notes
A close event was added for the wx timer app.
7.2.0release notes
Fixes ContextVars persisting between cells.
7.1.0release notes
Uses the kernel launching thread instead of assuming the main thread, fixing failures of asserts when kernels launch in new threads.
7.1.0release notes
Fixes keyboard interrupts on Windows by manually resetting the interrupt event.
7.1.0release notes
Fixes display of Matplotlib plots in separate windows.
7.1.0release notes

Runs the control channel in a separate thread, which may change the order in which messages are processed.
6.0.0release notes
Removes find_connection_file and the profile argument of connect_qtconsole and get_connection_info.
6.0.0release notes
Removes the deprecated module; the notes direct users to import similar functionalities from ipyparallel.
6.0.0release notes
The isatty method returns true, which can improve some output such as colored output but may break other output.
6.0.0release notes
Updates the Python requirement to 3.7.
6.0.0release notes
Captures stdout and stderr output, including subprocesses and compiled libraries; some frontends may show duplicated output.
6.0.0release notes
Changes the default timeout to 0.0 seconds.
6.0.0release notes

Deprecates Kernel._parent_header; use .get_parent() instead.
6.0.0release notes
Multiple shell streams are ignored and Kernel.shell_streams is deprecated; use Kernel.shell_stream instead.
6.0.0release notes

Adds the ability to set a cell name.
6.0.0release notes
Adds debugger protocol support, enabling debugger functionality in JupyterLab, RetroLab, and other compatible frontends.
6.0.0release notes
Implements the inspectVariables request; returned variables also include a type field.
6.0.0release notes
Adds Kernel.get_parent_header.
6.0.0release notes