[BUG] conda u8darts installation on macOS arm64

[daidahao]

Describe the bug
u8darts cannot be installed on macOS-arm64 platforms and Python 3.13 via conda or mamba. This is probably due to the missing prophet conda release on macOS-arm64 and Python 3.13.

To Reproduce
Steps to reproduce the behavior, preferably code snippet.

mamba install u8darts-all
mamba install -c conda-forge -c pytorch u8darts-all
conda install -c conda-forge -c pytorch u8darts-all

conda-forge/noarch                                          Using cache
conda-forge/osx-arm64                                       Using cache
pytorch/noarch                                              Using cache
pytorch/osx-arm64                                           Using cache

Pinned packages:

  - python=3.13

error    libmamba Could not solve for environment specs
    The following packages are incompatible
    └─ u8darts-all =* * is not installable because there are no viable options
       ├─ u8darts-all [0.22.0|0.23.0|...|0.41.0] would require
       │  ├─ prophet >=1.1.1 *, which does not exist (perhaps a missing channel);
       │  └─ u8darts [==0.22.0 pyhd8ed1ab_0|==0.23.0 pyhd8ed1ab_0|==0.23.1 pyhd8ed1ab_0|==0.24.0 pyhd8ed1ab_0], which requires
       │     └─ prophet >=1.1.1 *, which does not exist (perhaps a missing channel);
       ├─ u8darts-all [0.10.0|0.10.1|...|0.9.1] would require
       │  └─ pystan >=2.19.1.1,<3.0.0.0 *, which does not exist (perhaps a missing channel);
       └─ u8darts-all 0.21.0 would require
          └─ u8darts ==0.21.0 pyhd8ed1ab_0, which requires
             └─ prophet >=1.1 *, which does not exist (perhaps a missing channel).
critical libmamba Could not solve for environment specs

Expected behavior
A clear and concise description of what you expected to happen.

System (please complete the following information):

• Python version: 3.13.12
• u8darts version: 0.41.0
• conda version: 25.11.1
• mamba version: 2.4.0

Additional context
Add any other context about the problem here.

[dennisbader]

Yeah, technically we do not offer python 3.13 support yet for the darts[all] flavor. We did not want to enforce python<3.13 since dependencies might add support for it at a later stage (and users can install another darts option without prophet).

Out of interest, does the pip install darts[all] works on 3.13?

[daidahao]

@dennisbader

Out of interest, does the pip install darts[all] works on 3.13?

Yes, pip or uv install darts[all] works on 3.13 because prophet provides macOS-arm64 binaries on PyPI.

The issue here has less to do with Python 3.13, than with Prophet not releasing macOS-arm64 binaries on conda-forge. Darts is not at blame here, but perhaps we could make Prophet optional while waiting for macOS-arm64 prophet on conda-forge?