Power Automate Expression Builder

Version: 1.0.9

Power Automate Expression Builder is a React and TypeScript app for building Trigger Condition and Filter array advanced-mode predicates inside the Power Platform Toolbox. It uses a pure expression engine and shared Fluent UI v9 builder UI, with a thin host bootstrap for PPTB.

Package Boundaries

packages/engine: pure TypeScript expression formatting and diagnostics
packages/platform: PPTB platform adapter
packages/builder-ui: shared Fluent UI v9 Concept C composer
apps/pptb: Power Platform Toolbox bootstrap

Setup

This workspace requires Node 24.17.0 on the active 24.x LTS line, matching the workspace engines fields and the root-owned Vite 8 / @vitejs/plugin-react 6 toolchain.

If you use nvm, the repo root includes .nvmrc:

nvm use

Install dependencies from the repo root:

npm install

The app workspace inherits Vite, TypeScript, and the React plugin from the repo root. Do not add duplicate toolchain entries to apps/pptb unless the workspace layout changes.

Development

Theme edits belong in packages/builder-ui/src/theme/workbenchTokens.ts. fluentTheme.ts only mirrors that runtime source for compatibility exports.

Run the Power Platform Toolbox host:

npm run dev:pptb

When loading the Power Platform Toolbox package, rebuild first so the emitted dist artifacts include the latest builder-ui theme changes:

npm run build:pptb

Verification

Run the fast checks from the repo root:

npm run lint
npm run typecheck
npm test

Run end-to-end smoke tests:

npm run test:e2e

Build

Build the PPTB host:

npm run build:pptb

Preview a build:

npm run preview:pptb

Docs

• PPTB Usage
• User manual & developer docs