Slim System in user nim.cfg breaks nimble

[c-blake]

NOTE: this clobbers your nim.cfg if that matters to you and may need leading directory creation..

echo define:nimPreviewSlimSystem > $HOME/.config/nim/nim.cfg
nimble install nimble

yields

Downloading https://github.com/nim-lang/nimble using git
       Tip: 4 messages have been suppressed, use --verbose to show them.
packageparser.nim(393)   readPackageInfo

    Error:  Could not read package info file in /tmp/nimble_17752/githubcom_nimlangnimble/nimble.nimble;
        ...   Reading as ini file failed with:
        ...     Invalid section: .
        ...   Evaluating as NimScript file failed with:
        ...     /tmp/nimblecache-1979690426/nimscriptapi_1508423453.nim(168, 7)
Error: undeclared identifier: 'writeFile'
        ... candidates (edit distance, scope distance); see '--spellSuggest':
        ...  (4, 4): 'outFile'
        ...  (4, 4): 'scriptFile'
        ...  (4, 6): 'moveFile'
        ...  (4, 6): 'rmFile'
        ...  (4, 6): 'sameFile'
        ...  (4, 6): 'splitFile'
        ... printPkgInfo() failed.

then if you rm $HOME/.config/nim/nim.cfg it works fine.

Contextual version information:

Nim Compiler Version 1.9.1 [Linux: amd64]
Compiled at 2022-12-24
Copyright (c) 2006-2022 by Andreas Rumpf

active boot switches: -d:release -d:danger -d:nimUseLinenoise -d:nimHasLibFFI

but this has been a problem for me ever since I started testing nimPreviewSlimSystem.

Could be as easy as adding std/syncio .. somewhere.