Newinstall/lsstsw changed to use mambaforge

Problems have been occurring with the miniconda base installation used by newinstall and lsstsw. First, issues came up on macOS (which have prevented binary package builds), but last night the mamba solver installation into the base environment started failing on Linux as well.

As of the merge of DM-39985 this morning, newinstall and lsstsw will now use the more modern mambaforge as their base conda installation. mambaforge has been used in lsstinstall since its inception.

No user impact is expected. If any problems are observed, please let me know or post here.

Thanks for the heads-up on this, K-T. I hope you won’t mind if I ask a related question not directly related to lsstsw.

As a long-time miniconda user, I’m not entirely clear on what a move to mambaforge entails, particularly since the Mamba installation instructions discourage installing Mamba itself on top of an existing Conda installation (though I’ve done that and so far haven’t encountered problems).

If I’d like to move to mambaforge, should I remove my existing miniconda installation and start from scratch (thus needing to re-create existing envs)? Or can mambaforge exist alongside an existing miniconda installation, easing a transition?


As far as I know, the environments managed by conda and mamba are identical. I have a number of environments in my home directory that I can activate with both a mambaforge conda and a miniconda conda (even at the same time in different shells).