id: ADR-0002 title: Name the project pse-arrow, prefix crates pse-, dual-license MIT OR Apache-2.0 status: accepted date: 2026-09-13 deciders: [paul-heyse] level: decision principles: [DM-11, DM-55] blueprint: [§3.2, §26] review: not-required: naming, licensing and distribution carry no semantic surface; blueprint §26 lists the prefix as “placeholder, to confirm” evidence: Interface-checked supersedes: [] superseded-by: null revisit: The PyPI name pse becomes available, or a crates.io name collision forces a different crate prefix at the phase-0 publish verification: tests/governance/tests/every_crate_registered.rs (crate prefix); governance / reuse (reuse lint over the SPDX headers)

ADR-0002: Name the project pse-arrow, prefix crates pse-, dual-license MIT OR Apache-2.0

Context

Blueprint §3.2 leaves the pse- prefix as a placeholder and §26 carries “crate naming and repository layout” as an open decision. The repository needs one name on GitHub, on crates.io and on PyPI before anything is published.

Scope

Binds the repository name, the crate prefix, the Python import name, the PyPI distribution name and the license expression. It does not bind when anything is published (ADR-0034 and the register cover that).

Drivers

One name that reads the same in three registries; a license that lets the Rust and Python ecosystems both consume the result; a prefix short enough for 23 crates.

Options

idaes-rs or anything with idaes in it — rejected: implies affiliation (ADR-0003). Import name pse_arrow — rejected: the import name is what appears in every example; pse is short and unambiguous inside the package. Apache-2.0 only — rejected: the Rust ecosystem’s default is the dual license.

Outcome

Repository paul-heyse/pse-arrow; crate prefix pse-*; Python import name pse; PyPI distribution pse-arrow because PyPI pse is already taken; license MIT OR Apache-2.0 with LICENSE-MIT, LICENSE-APACHE, LICENSES/ and a two-line SPDX header on every authored source file.

Consequences

The distribution name and the import name differ, which every install instruction has to state. REUSE.toml covers headerless file types by glob so Markdown needs no header; the code generator emits the header itself.

Compensating controls

reuse lint in python / lint; tests/governance/tests/every_crate_registered.rs asserts every workspace member carries the prefix and is listed in the blueprint §3.2 layout.

Confirmation

pip install pse-arrow then import pse is the documented pair; README.md and docs/README.md state it in the first paragraph.

Pros and cons

The mismatch between distribution and import name is a real papercut, accepted because pse is the name the blueprint uses throughout §3.2 and renaming 23 crates later is worse.

More information

Blueprint §3.2 (workspace layout) and §26 (open decisions); REUSE.toml; ADR-0003 for the non-affiliation statement.

Status history

• 2026-09-13 — accepted with the repository-seeding pull request (backfilled from blueprint revision 3).