The Internet, 17 June 2026

I'm happy to announce pyacid v0.5.0 — our first final (non-alpha-tagged) version number. About 5 changes over 8 commits since v0.5.0a1; highlights below, see the website for the rest.

WARNING: acid is alpha software, developing rapidly — the API will change between releases. Pin a version (pip install pyacid==0.5.0) for anything you rely on, and watch these emails for what changed.

Headline new features:

This release was largely about working around issues specific to running on the Rubin Science Pipeline (RSP) at USDF (slow filesystems, no local scratch). We also fixed a cdshealpix versioning issue (RSP has a version that is too old).

Bottom line: cone downloads are now practical on the RSP: grab just the patch of sky around your target field instead of the whole catalog.

# RA, Dec, radius in degrees — pulls only the partitions overlapping the cone
acid download gaia_dr3 gaia --cone 150.1,2.2,1.0
acid list gaia    # confirm it's on disk and ready to open

Before, a cone download could grind for minutes and burn several GB building its sky-footprint map — and stall outright on a small or busy /tmp. Now it's quick and light, so pulling a region around your object actually works on a laptop or a shared login node.

Upgrade: pip install -U pyacid · Full changelog →

Also new:

• acid now honors $TMPDIR (and a new $ACID_TMPDIR) everywhere — the CLI and notebooks — so on a batch node your scratch files land on fast node-local disk instead of a tiny shared /tmp.
• Clearer errors: a TLS certificate failure on a download host now tells you exactly how to fix your trust store, and acid.open(<url>) fails with a real message instead of a cryptic "could not determine order." This happens on macOS when the user installs Python.org Python, yet forgets to run the Certificate Install step.

Heads-up: acid now prefers your environment's $TMPDIR over the config-file tmpdir setting (so a batch system's node-local scratch is picked up automatically). If you relied on the config tmpdir while $TMPDIR was set, set $ACID_TMPDIR to override it. See the changelog.

Thanks for your time — as always, see the website and documentation for the details. If you hit any problems or have feature ideas, open an issue at github.com/mjuric/acid-issues.

— Mario & his AI buddies