ALPS 3.0 — release scheduled for 15 September 2026

[vws100]

ALPS 3.0 is the first major release since 2.0, and the first developed
under the project's new NSF POSE-supported governance model. We're
announcing the schedule now so users can test the release candidates
against their own workflows.

Schedule

• Aug 21 — feature freeze, release/3.0 branch cut
• Aug 25 — 3.0.0-rc.1
• Sept 1 — 3.0.0-rc.2
• Sept 8 — code freeze
• Sept 15 — 3.0.0

What's in 3.0

• Breaking: relicensed under MIT. The previous ALPS library and
  application licenses are replaced throughout. The citation request
  remains — per-application citations print at runtime and are listed
  in CITATIONS.txt.
• Breaking: VisTrails provenance integration removed. Python is now
  the sole evaluation path. Per-release Zenodo DOIs replace VisTrails
  as the archival/reproducibility mechanism.
• Breaking: modern toolchain baseline. C++17, CMake > 3.18,
  Boost >= 1.76, Python >= 3.9, NumPy 2.0 compatible. Tested on
  GCC 10.5-14.2, Ubuntu 24.04 and macOS 14/15.
• Deprecated: dwa and MPS. Both emit deprecation warnings in 3.0
  and are scheduled for removal in .
• Binary install via pip. pip install pyalps — no compilation, no
  admin privileges. Note the binary build is serial; MPI parallelism
  requires the source or Spack install.
• Spack packages for HPC and cluster installs, in the upstream Spack
  package repository.
• Rebuilt documentation and tutorials, including Jupyter-notebook
  tutorials, a "which code to choose" guide, and localized content
  (site in English, Chinese, and Japanese).
• DMRG upgrade and fixes, including a crash in temporary-file creation, plus a
  large build-compatibility cleanup, and a significant speedup

Development has moved to GitHub with CI, automated wheel builds, and
regression testing; the pre-2.4 codebase remains available at
ALPSim/legacy.

How to help

Build the release candidates against your own workflows and report
breakage on the tracker (#116). Platform and compiler reports are the
most useful thing you can send us — that's the failure mode we can't
reproduce locally. If you rely on VisTrails, dwa, or MPS, please tell
us now rather than after Sept 15.

Scope is frozen as of the milestone: https://github.com/ALPSim/ALPS/milestone/2

A companion release paper is in preparation and will be posted to arXiv
after 3.0 release on GitHub.

[vws100]

@ALPSim/core — the 3.0 schedule above is now the working plan. Two things
I need from you this week:

1. Confirm or correct your section of the feature list. Anything you
own that's listed above and isn't actually landed on master, say so now
— it comes out of the announcement rather than out of the release.

2. Claim your items on the tracker (#116). The open questions are the
worm-code update, the MPS deprecation scope and removal version, DMRG functioning, and the
PyPI package name. Comment on the tracker with what you're taking.

Feature freeze is Aug 21. Anything not merged by then ships in 3.1 —
scope moves, the date doesn't.

If you think Sept 15 is unrealistic, this thread is the place to say it,
and this week is the time.