App Overview

Sample Appnest app

A frontend and backend app built on the Appnest stack: you implement business logic and UI; the framework and engine handle dev routing, HTTP wiring, React setup, and bundling for local development and pack.

• Backend — See App Backend (app-backend/server.js, manifest registration, $fetch, $db, etc.).
• Frontend — See App Frontend (React root, Twigs, calling the backend, { statusCode, body } vs SDK helpers).

At a high level every app root has three pillars:

1. app-frontend/ — UI users see (plus optional app-install-frontend/).
2. app-backend/ — Server code the platform invokes; exports must match manifest.json.
3. manifest.json — Declares locations, functions, events, installation_parameters, OAuth, and whitelisted_domains.

For the development engine (proxy, CLI, zip), see Overview and Commands.

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Project structure

Path	Required?	Role
app-backend/	Yes	server.js — backend entry; exports drive API + events.
app-frontend/	Yes	Main React (or template) UI; built dist for pack.
app-install-frontend/	Optional	Separate install / onboarding UI.
manifest.json	Yes for packaging	Platform contract (see Configuration below).
.env	Recommended	Ports, pack paths, CLIENT_SCRIPT_URL, …

Edit app-* trees and root config only—not appnest-* engine packages.

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Configuration

Topic	Document
Manifest schema, examples, installation_parameters, OAuth tables	Manifest
Product UI locations (full_page_app, …)	Product Location

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Appnest Functions (summary)

Platform-backed helpers: backend modules inside app-backend, and frontend helpers to call named server functions.

Overview: Appnest Functions

Surface	Doc
Backend modules ($fetch, $db, $file, $schedule, $next, …)	App Backend (table + links to each topic)
Frontend invoke (appBackendInvoke, global client, …)	App Frontend & Frontend Functions

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Day-to-day commands

From the app root (next to manifest.json):

appnest-development-engine app init       # scaffold
appnest-development-engine app start      # proxy + backend + frontends
appnest-development-engine app validate   # lint + manifest
appnest-development-engine app pack       # build + zip

• validate — Backend + frontend lint and manifest.json checks.
• pack — Usually app-frontend, app-backend, optional app-install-frontend, manifest.json, .env, plus optional PACK_FOLDER_PATHS / PACK_FILE_PATHS.
• Treat .env as sensitive.

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Cross-cutting reminders

• process.cwd() is the project root; the engine uses ORIGINAL_CWD for child processes (see engine docs).
• Keep manifest, server.js exports, and docs aligned when renaming or adding functions.

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Full documentation (this developer site)

Topic	Document
Backend entry, SDK modules, rules	App Backend
Frontend entry, Twigs, invoke patterns, UX	App Frontend
Manifest & locations	Manifest, Product Location
Appnest Functions concept + deep links	Appnest Functions overview
Engine & CLI	Development Engine overview, Commands
Twigs component library (external)	twigs.surveysparrow.com