# Oh My Pi v17.2.8: omptype schema engine upgrades

> Oh My Pi v17.2.8 upgrades the bundled omptype schema engine with intersection and pipe operators, bigint and RegExp literals in the string DSL, Standard Schema V1 interop, fromJsonSchema() for rebuilding schemas from JSON Schema documents, $defs/$ref emission for recursive aliases, an AnyType constraint, and richer union/collection error reporting. Default() values now materialize for undefined input, and .narrow()/.filter() accept OmpErrors returns.

| | |
|---|---|
| **Tool** | Oh My Pi |
| **Version** | v17.2.8 |
| **Kind** | release |
| **Published** | 2026-08-04 |
| **Observed** | 2026-08-21 |
| **Significance** | 3/5 |
| **Breaking** | no |
| **Categories** | feature, capability |

## What changed


- Intersection and pipe operators in schema DSL
- BigInt and RegExp literal support in string DSL
- Standard Schema V1 interop (`~standard` with synchronous validation)
- `fromJsonSchema()`: rebuild callable schemas from JSON Schema (draft-07/2020-12)
- `$defs`/`$ref` emission for recursive alias schemas in `toJsonSchema()`
- `AnyType` for generic functions accepting any schema
- Root `.default()` materializes for `undefined` input
- `.narrow()`/`.filter()` accept `OmpErrors` returns
- `io: 'input'` / `io: 'output'` options on `toJsonSchema()`
- Lazy activation of advanced normalization for low-overhead construction
- `.default()` typed input-side, marks input as optional
- Parse keywords union-aware in inference
- Alias intersections defer through memoized lazy nodes (fixes cyclic scope stack overflow)


## Sources

- [github_release](https://github.com/can1357/oh-my-pi/releases/tag/v17.2.8) — retrieved 2026-08-21


## Community

_No curated reactions recorded. Facts and community takes are kept in separate layers
and never blended._

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Canonical: https://changelogs.info/oh-my-pi/v17-2-8
Entity: https://changelogs.info/oh-my-pi
Event ID: `evt_2026-08-04_oh-my-pi_v17-2-8`
Licence: event synthesis © changelogs.info, CC BY 4.0. Linked sources belong to their vendors.