Lythonic

**Full Changelog**: https://github.com/walnutgeek/lythonic/compare/v0.0.26...v0.0.27

[Release notes](https://github.com/walnutgeek/lythonic/blob/v0.0.27/docs/release_notes/v0.0.27.md)

**Full Changelog**: https://github.com/walnutgeek/lythonic/compare/v0.0.25...v0.0.26

[Release notes](https://github.com/walnutgeek/lythonic/blob/v0.0.26/docs/release_notes/v0.0.26.md)

**Closed**:
- 12 Triggers: re-activation resets last_run_at, so runs missed while down are never caught up

Full Changelog: https://github.com/walnutgeek/lythonic/compare/v0.0.24...v0.0.25

Release notes (https://github.com/walnutgeek/lythonic/blob/main/docs/release_notes/v0.0.25.md)

Closed:
- 11 state: a None filter silently matches nothing; need IS NULL support in select

Full Changelog: https://github.com/walnutgeek/lythonic/compare/v0.0.23...v0.0.24

Release notes (https://github.com/walnutgeek/lythonic/blob/main/docs/release_notes/v0.0.24.md)

ADRs:
- 0003 Symmetric matrix storage is a canonical two-variant union (https://github.com/walnutgeek/lythonic/blob/v0.0.24/docs/adr/0003-symmetric-storage-canonical-union.md)
- 0004 Positive semi-definiteness is a query, not an invariant (https://github.com/walnutgeek/lythonic/blob/v0.0.24/docs/adr/0004-psd-is-a-query.md)
- 0005 KeyedVector admits non-finite values (https://github.com/walnutgeek/lythonic/blob/v0.0.24/docs/adr/0005-keyed-vector-admits-non-finite-values.md)

Closed:
- 9 SymmetricMatrix: square, string-keyed, symmetry-by-construction matrix
- 10 KeyedVector: a universe plus one value per key

Full Changelog: https://github.com/walnutgeek/lythonic/compare/v0.0.22...v0.0.23

Release notes (https://github.com/walnutgeek/lythonic/blob/main/docs/release_notes/v0.0.23.md)

ADRs:
- Exposure matrices are immutable; all growth happens in a builder (https://github.com/walnutgeek/lythonic/blob/v0.0.23/docs/adr/0001-immutable-matrix-with-builder.md)
- Exposure records serialize as index triples (https://github.com/walnutgeek/lythonic/blob/v0.0.23/docs/adr/0002-exposure-records-as-index-triples.md)

Closed:
- 7 Sparse keyed exposure matrix (Universe, ExposureMatrix, ExposureMatrixBuilder)
- 8 Retrofit FrameData to the pd/pl/pa facade pattern (breaking)

Title: v0.0.22: FrameData — library-agnostic tabular model with pandas/polars/pyarrow conversion

Full Changelog: https://github.com/walnutgeek/lythonic/compare/v0.0.21...v0.0.22

Release notes (https://github.com/walnutgeek/lythonic/blob/main/docs/release_notes/v0.0.22.md)

Design docs:
https://github.com/walnutgeek/lythonic/tree/v0.0.22/docs/superpowers/specs/2026-06-16-frame-data-design.md