Compatibility Overview¶

These packages exist to reduce migration breakage, not to become the preferred long-term entrypoints for new work.

This page should help readers see the compatibility layer as a bridge with a cost. Preserving old names is sometimes necessary, but it is still a debt that should be visible and justified.

These compatibility pages should make legacy names understandable without romanticizing them. Their value is in helping readers migrate with less ambiguity, not in making the old names feel equally current.

Visual Summary¶

flowchart TB
    page["Compatibility Overview<br/>clarifies: map old names | choose migration | judge retirement"]
    classDef page fill:#dbeafe,stroke:#1d4ed8,color:#1e3a8a,stroke-width:2px;
    classDef positive fill:#dcfce7,stroke:#16a34a,color:#14532d;
    classDef caution fill:#fee2e2,stroke:#dc2626,color:#7f1d1d;
    classDef anchor fill:#ede9fe,stroke:#7c3aed,color:#4c1d95;
    classDef action fill:#fef3c7,stroke:#d97706,color:#7c2d12;
    legacy1["distribution names"]
    legacy1 --> page
    legacy2["import names"]
    legacy2 --> page
    legacy3["command names"]
    legacy3 --> page
    canon1["new work"]
    page --> canon1
    canon2["current handbook surfaces"]
    page --> canon2
    canon3["current packages"]
    page --> canon3
    pressure1["migration pressure"]
    pressure1 -.should shorten the life of.-> page
    pressure2["retirement readiness"]
    pressure2 -.should shorten the life of.-> page
    pressure3["do not normalize the old name"]
    pressure3 -.should shorten the life of.-> page
    class page page;
    class legacy1,legacy2,legacy3 caution;
    class canon1,canon2,canon3 positive;
    class pressure1,pressure2,pressure3 action;

Preserved Surfaces¶

legacy distribution names
legacy Python import names
legacy command names where they still exist

Concrete Anchors¶

packages/compat-* for the preserved legacy packages
the compatibility package README.md files for canonical targets
the matching canonical package docs for current behavior and new work

Use This Page When¶

you are tracing a legacy package name back to its canonical replacement
you need migration guidance rather than product implementation detail
you are deciding whether a compatibility surface still deserves to exist

Decision Rule¶

Use Compatibility Overview to decide whether a preserved legacy name is still serving a real migration need. If the only reason to keep it is habit rather than an identified dependent environment, the section should bias the reviewer toward migration or retirement planning.

What This Page Answers¶

which legacy surface is still preserved
when new work should move to the canonical package instead
what evidence would justify retiring a compatibility package

Reviewer Lens¶

compare legacy names here with the compatibility package metadata and README targets
check that migration advice still points at current canonical docs
confirm that compatibility language does not accidentally encourage new work to start here

Next Checks¶

move to the canonical package docs once the current target package is known
inspect compatibility package metadata if the question is about what remains preserved
use this section again only when evaluating migration progress or retirement readiness

Honesty Boundary¶

This section documents preserved legacy surfaces, but it does not claim those legacy names are the preferred place for new work or long-term design growth. If a legacy name remains, that is a migration fact, not a design endorsement.

Purpose¶

This page gives the shortest honest description of why the compatibility packages remain.

Stability¶

Keep it aligned with the actual compatibility promises that are still checked in.