# Roadmap

tilearray turns remote tile services into Dask-backed xarray arrays for **geo data engineers**: a large AOI becomes a polite fetch-and-assemble problem, with a clear memory / concurrency / lazy-vs-cache story and the **same API** from a laptop to a larger machine.

We prefer **fewer, meaningful releases**. Work lands on `main` continuously; PyPI is cut when a theme’s exit criteria clear — not as feature drip.

```text
  0.1.x (shipped)          0.2                      0.3                         1.0
  open alpha proof    →    trustworthy core    →    scale + hosts          →    stable contract
```

Tracking lives in GitHub milestones (linked below once published) and a small set of thematic issues — not one ticket per checklist cell.

## 0.2 — Trustworthy core

Make the installed library boringly reliable on the documented paths: fix objective-blocking engineering debt without expanding the protocol surface.

- Replace or quarantine the GeoTIFF decode spine (drop the fragile zarr pin cage)
- Analysis-ready CRS / attrs and a documented rioxarray handoff
- One canonical compute habit and a fresh stranger first-look pass
- Large-AOI politeness evidence / nightly soak under presets
- Start HTTP consolidation (capabilities → httpx or one UA/timeout policy)

**Exit criteria for tagging 0.2.0**

- [ ] Clean-env `pip install tilearray` + WCS GeoTIFF + XYZ quickstarts succeed without pin gymnastics
- [ ] Documented attrs/CRS story sufficient for xarray → plot / simple rioxarray on EA + GIBS/OSM examples
- [ ] Fresh stranger first-look: install → mosaic succeeds; no contradictory compute guidance on primary paths
- [ ] CHANGELOG theme is coherent; attestations appear on this (or the immediately prior) PyPI artifact
- [ ] No known silent mosaic corruption on documented RGB / single-band GeoTIFF paths

Milestone: [0.2 Trustworthy core](https://github.com/MatthewJWhittle/tilearray/milestone/1)

## 0.3 — Scale & hosts

Big AOI on more real hosts, safely — including “larger machine” without a second API.

- Host preset pack (USGS / GIBS / keyed XYZ pattern)
- Larger-machine / distributed “don’t stampede” story
- WMTS productization (guide + tests)
- AOI/grid ergonomics + fetch summary UX

**Exit criteria for tagging 0.3.0**

- [ ] ≥1 additional WCS and ≥1 WMTS/WMS host with preset or first-class recipe + visual guide
- [ ] Written + tested guidance for scaling beyond a laptop that preserves host ceilings
- [ ] Large-AOI soak evidence (hundreds–thousands of tiles on at least one preset host) in docs or benchmarks
- [ ] WMS/WMTS contract coverage no longer the weak sibling of WCS

Milestone: [0.3 Scale & hosts](https://github.com/MatthewJWhittle/tilearray/milestone/2)

## 1.0 — Stable contract

Freeze the public API users already rely on; graduate from Alpha.

- Public API freeze / Alpha graduation checklist
- Hardening (property tests, stronger nightly, supported Python matrix)
- Docs maturity (deeper API reference; optional versioned docs later)

**Exit criteria for tagging 1.0.0**

- [ ] Stability guarantee published; Alpha badge removed
- [ ] North-star success criteria met on supported Python versions
- [ ] No S0 gaps open; S1 gaps closed or explicitly accepted in docs as known limits
- [ ] Provenance/attestations on the 1.0 artifact; release checklist boring

Milestone: [1.0 Stable contract](https://github.com/MatthewJWhittle/tilearray/milestone/3)

## Non-goals (through ~0.3)

1. **STAC / COG cube builder** — leave to stackstac / odc-stac / rioxarray; interoperate, don’t duplicate.
2. **Map SDK or tile server** — no Leaflet/Cesium UI; no OWS-style serving.
3. **Async-first rewrite** — sync httpx + Dask threads stays the laptop-friendly model unless evidence forces otherwise.
4. **GDAL on every path** — optional extra later is fine; basic XYZ should not require full GDAL.
5. **Many tiny PyPI releases** — batch on `main`; cut when a theme exits.
6. **Universal host coverage / ToS-grey demos** — presets only where politeness and licensing are clear.
7. **Full temporal datacube API** — year/layer switching stays recipe-level until the spatial large-AOI story is solid.
8. **Rewriting Sphinx onto another docs stack** — the usage-guides pipeline stays unless it fails the visual/live-host preference.

## See also

- {doc}`how-it-works` — plan → polite fetch → mosaic
- {doc}`example-sources` — public endpoints and presets
- {doc}`building-docs` — maintainer notes for Sphinx and figures
- [GitHub milestones](https://github.com/MatthewJWhittle/tilearray/milestones)
- [Open issues](https://github.com/MatthewJWhittle/tilearray/issues)