python plugin doesn't support base "core20"
Metadata
Current evaluation
Closed without a recorded fix after years of inactivity. Snapcraft 4.0 added core20 support, but i386 had no core20 base and external-symlink lint failures remained.
Resolution: closed stale
Reason: The Launchpad record shows no resolving commit, merged PR, or closing fix; it remained open for years and was closed without a recorded resolution after core20 Python builds were confirmed problematic. The maintainer also confirmed that i386 was unsupported because no i386 core20 base exists.
Evaluated by: mr-cal-bot
No scores available.
Issue body
I'm trying to build snap based on fresh Ubuntu 20.04 LTS. On my machine snapcraft build fails with weird reasons:
user@hp:~/src/udp-over-tls-pool> snapcraft
Launching a VM.
Project base changed from None to 'core20', cleaning build instance.
delete failed: The following errors occurred:
instance "snapcraft-udp-over-tls-pool" does not exist
An error occurred with the instance when trying to delete with 'multipass': returned exit code 2.
Ensure that 'multipass' is setup correctly and try again.
user@hp:~/src/udp-over-tls-pool> snapcraft
Launching a VM.
launch failed: Unable to find an image matching "core20"
An error occurred with the instance when trying to launch with 'multipass': returned exit code 2.
Ensure that 'multipass' is setup correctly and try again.
These two errors alternate each other: for example, odd run of snapcraft ends up with missing core20 image error, even runs of snapcraft ends up with instance "snapcraft-udp-over-tls-pool" does not exist
Cloud build of same snapcraft.yml ends with:
Running pull phase...
The plugin used by part 'udp-over-tls-pool' does not support snaps using base 'core20'.
Build failed
It seems new Ubuntu was released, but there are still no usable base images for core20 and no support from plugins.
Additional info: application source is located here: https://github.com/Snawoot/udp-over-tls-pool
snapcraft.yaml is attached to this report.
Evaluation history
| Date | Model | Scores | Action | Summary |
|---|---|---|---|---|
| stealth/space-bunny-alpha | — | closed stale | Closed without a recorded fix after years of inactivity. Snapcraft 4.0 added core20 support, but i386 had no core20 base and external-symlink lint failures remained. | |
| stealth/space-bunny-alpha | — | closed stale | Closed without a recorded fix after years of inactivity; core20 Python builds remained problematic, and i386 lacked a core20 base. | |
| stealth/space-bunny-alpha | — | closed stale | Closed with no recorded resolution after years of inactivity; Launchpad bug #1874920 reported that Snapcraft’s Python plugin did not support the new core20 base. | |
| qwen/qwen3.6-35b-a3b | — | — | Closed without comments or explicit resolution. Support for the core20 base in the Python plugin was later added in subsequent snapcraft releases, superseding this report. | |
| qwen/qwen3.6-35b-a3b | — | — | Closed as abandoned due to inactivity. Core20 support was later added to the Python plugin in subsequent snapcraft releases. | |
| qwen/qwen3.6-35b-a3b | — | — | Python plugin lacked core20 base support, causing snapcraft build failures. Closed without comments or resolution, indicating the report was abandoned or superseded by updated plugin versions that now support core20. | |
| qwen3.6-35b-a3b-mtp-q6 | — | — | Closed without resolution. The python plugin initially lacked core20 base support, causing build failures. Snapcraft later added core20 compatibility, rendering this issue obsolete. |
Update history
| Date | Change |
|---|---|
| created |
Related work
-
Related To:
snapcraft#4087
(confidence 78%)
A later Snapcraft PR added core20 support for pyproject.toml Python plugin projects, addressing only part of the reported Python/core20 problem.
Related issues
| Issue | Project | State | Summary | Similarity |
|---|---|---|---|---|
| #1862256 snapcraft should complain loudly when building base: core20 snap on i386 | snapcraft (launchpad) | closed | Closed as superseded: improved architecture parsing rejects unsupported core20/i386 builds, making a dedicated check unnecessary; snapcraft#4392 improved this handling. | |
| #1866300 snapcraft fails to build core20 snap | snapcraft (launchpad) | closed | Closed without a documented fix after core20 Multipass/LXD failures; core20 build-base support was unavailable and the workaround was destructive mode. | |
| #1842328 snapcraft make plugin does not support core20 | snapcraft (launchpad) | closed | Core20 support for the make plugin landed via snapcore/snapcraft#2761 (commit 144814b29), superseding #2757 and unblocking UC20 gadget builds. | |
| #1660 Python plugin fails on core26: base snap does not include Python interpreter | craft-parts | open | core26 lacks a Python runtime, so Python-plugin builds fail unless Python is staged. Documentation covers the workaround, and maintainers are pursuing clearer warning guidance. | |
| #2161192 python plugin not working at all with snapcraft 9+ | snapcraft (launchpad) | open | Core26 Python plugin builds and module loading were fixed; packaging Python separately is now documented as required by the base. | |
| #2362 python plugin: add support for bases | snapcraft | merged | Merged in snapcraft#2362 via commit 669eebe19, making the Python plugin base-aware for core16/core18 and moving its tests to spread. | |
| #3079 cli: add plugin help for core20 | snapcraft | merged | Merged in canonical/snapcraft#3079 (04bf14915), adding core20 plugin help, Click paging, Python/nil v2 help fixes, and a core20 base fallback. | |
| #4138 core20: support PEP 518 in the python plugin | snapcraft | closed | core20 python plugin now supports PEP 518 sources with only pyproject.toml and no setup.py, merged in PR #4087 (commit 2d596621d) and shipped in Snapcraft 8; core20 support later removed by #6241. |