tempest-core 0.5.0

Renderer-agnostic UI core (IR, reconciler, state, style, widgets) shared by tempestroid and tempestweb.

tempest-core

📚 Documentation: Português (Brasil) · English (US) — bilingual, on GitHub Pages.

Renderer-agnostic UI core shared across the tempest stack — the engine behind both tempestroid (native renderers: Qt / Compose / Android) and tempestweb (DOM, WASM + server modes).

It is the one tree, many renderers core: the IR, the reconciler (build / diff), the state model (App), the typed style model (Style, Color, Edge), the widget and component trees, plus the cross-cutting helpers (animation, i18n, navigation, theme, validators). It carries no platform-coupled code — no Qt, no JNI, no Android, no DOM — so it imports cleanly under CPython, Pyodide and a headless server. Renderers live in the consumers; this package only produces and diffs the tree.

from tempest_core import App, Column, Text, Button, Style, build, diff

old = build(Column(children=[Text(content="Count: 0", key="label")]))
new = build(Column(children=[Text(content="Count: 1", key="label")]))
patches = diff(old, new)          # -> [Update(set_props={"content": "Count: 1"})]

Design system (Chakra-style variants → Material 3)

Components take Chakra-ergonomics props (variant/size/color_scheme) and a theme, and resolve a concrete Material 3 Style via pure resolvers in variants.py — resolve_variant (buttons), resolve_field_variant (text inputs / select / masked / autocomplete / pin), resolve_selection_variant (checkbox / switch), resolve_slider_variant (sliders) and resolve_surface_variant (cards / surfaces — H3). The interactive resolvers each ship a *_states sibling returning the per-state table (default/hover/pressed/disabled/focus) the renderers apply on real events; surfaces are non-interactive, so there is no state table. The touch target is held ≥ 48dp and WCAG-AA contrast is preserved. An explicit style= is always merged on top.

from tempest_core import CardVariant, IconButton, Theme
from tempest_core.components import Card, HStack, Surface, VStack
from tempest_core.widgets import Input, Spacer, Text
from tempest_core.style import FieldVariant

field = Input(value="", field_variant=FieldVariant.FILLED, color_scheme="primary")
button = IconButton(icon="settings", color_scheme="primary", label="Open settings")

# H3 styled surface & layout kit: cards/surfaces (elevated/filled/outlined) +
# SwiftUI-style stacks with token-step gaps + a flex Spacer.
card = Card(variant=CardVariant.OUTLINED, color_scheme="primary", children=[
    HStack(gap="md", children=[Text(content="Title"), Spacer(), Text(content="42")]),
])

The H3 surface kit (CardVariant, resolve_surface_variant, Surface, StyledContainer, HStack/VStack, Spacer) realizes Material 3 elevation as a Shadow mapped from the M3 level (elevation=0..5) — no new Style field. Card/Divider/ListTile/Accordion/Grid are themed off the tokens, and the old call sites stay backward-compatible.

Install

pip install tempest-core

Requires Python >=3.11. Only hard dependency: pydantic>=2.

Status

Extracted from tempestroid's vendored core. tempestweb consumes it directly (no vendored copy). tempestroid's own migration to depend on this package — with its full Qt↔Compose conformance suite green — is the next phase.

Develop

uv sync --extra dev
ruff check . && ruff format --check .
mypy tempest_core
pytest -q