Technologies

Every dependency in the free Hype Stack starter earns its place. Here is what is inside, how the repository is laid out, and why each piece is there.

Runtime zones

Runtime	What runs there	Examples
Browser	React UI, TanStack Router, HyperFetch client, theme tokens	`apps/frontend`, `apps/admin`
Node.js API	Hono server, Prisma, Kysely, Valkey, S3 client, WebSockets	`apps/backend`
Electron	Same frontend codebase in a native window	`pnpm --filter @hype-stack/frontend start:app`
Mobile	Expo app with expo-router and NativeWind	`apps/mobile`
Extension	Browser extension UI, same theme tokens	`apps/extension`
Local infra	Postgres, Valkey, object storage	`docker-compose.yml`

Build and tooling (Vite, Nx, Prisma CLI, oxlint) run on Node at the workspace root. They are not part of the production request path.

Repository layout

The project is a pnpm monorepo with Nx orchestrating tasks:

apps/
  backend/    # Hono API server
  frontend/   # React SPA (web + Electron)
  mobile/     # Expo app (expo-router, NativeWind)
  extension/  # Browser extension (Vite, Tailwind)
packages/     # Shared code (types, utils, configs)
docker-compose.yml
nx.json
pnpm-workspace.yaml
stack.json    # apps, paths, and which packs are installed

Installing a SaaS starter pack adds another app, apps/admin, plus auth, organizations, permissions, and admin routes under apps/backend. Feature packs (billing, teams, notifications) add more files into those apps. Every app deploys independently and talks to the API over HTTP, so restarting the API does not rebuild the UI.

Free template vs pack-added

Present after `create`	Arrives with a starter / feature pack
`apps/backend`, `apps/frontend`, `apps/mobile`, `apps/extension`	`apps/admin`
Prisma + Kysely + Valkey + S3 client	Auth, orgs, invitations, RBAC
Error middleware, websockets, HyperFetch SDK	Stripe billing, teams, notifications
Docker Compose, CI, agent rules	Pack-specific env vars and Prisma models

Backend

Technology	Role
Hono	HTTP framework. Fast, typed, runs on Node, Bun, Deno, and edge runtimes.
Prisma	Schema definition, migrations, and seeding. Also what packs merge into.
Kysely	Typed query builder for the joins, CTEs, and window functions Prisma cannot express cleanly.
PostgreSQL	Primary database.
Valkey (Redis)	Caching and session storage.
Zod	Request validation, and the source of the types the frontend SDK reads.

Two query tools is deliberate. Prisma owns the schema and migrations, Kysely owns the hard queries, and each is used for what it is good at.

Frontend

Technology	Role
React 19	UI library.
TanStack Router	Type-safe routing with typed params and plain-function loaders.
Tailwind CSS	Utility-first styling driven by semantic theme tokens.
shadcn/ui	Accessible component primitives, copied into the repo rather than installed.
HyperFetch	Data fetching, caching, and websockets through a generated typed SDK.
Electron	Desktop builds from the same codebase.

Mobile

Technology	Role
Expo	The mobile app runtime, with `expo-router` for file-based navigation.
NativeWind	Tailwind for React Native, reading the same theme tokens as the web apps.
EAS	Expo's build and submission service, driven by `deploy mobile`.

Local device testing uses Expo Go from sign.expo.dev. See Mobile.

Extension

Technology	Role
Vite	Builds the extension per browser family (chrome and firefox targets).
Manifest V3	The extension platform format the Chrome, Edge, and Firefox stores accept.
Tailwind CSS	Same utility classes and semantic theme tokens as the frontend.
Store APIs	`deploy extension` publishes to the Chrome, Edge, and Firefox stores.

Both apps talk to the same Hono API through HyperFetch, and both are themed by the CLI's theme picker alongside the frontend and admin.

Tooling

Technology	Role
Vite	Bundler and dev server for both web and Electron.
Nx	Monorepo task orchestration, so build, test, and lint run in the right order.
pnpm	Package manager with workspace support.
oxlint	Linter, Rust-based and fast enough to run on every save.
Vitest	Unit and integration tests on both sides.
Docker Compose	Local Postgres and Valkey in one command.
Sentry	Error and performance monitoring, wired but optional.

How types travel

There is no code generation step to remember and no schema language to maintain. A Hono route validated with Zod exposes its input and output types, HyperFetch builds a typed SDK from the Hono app type (registerRoutes return type), and the frontend imports only that SDK. Add an endpoint on the backend and it is typed on the client immediately. Change a response shape and the frontend stops compiling.

Read end-to-end type safety for the full chain, and HTTP for how components call the SDK.

What the free starter already handles

These are wired before you install a single pack:

Error handling. Typed error classes and one central error middleware that formats responses, logs, and reports to Sentry. Route code throws and moves on.
Real-time. Websocket listeners and emitters through the same typed SDK, with reconnection handled.
Caching. Valkey reads and writes that degrade gracefully instead of failing a request.
A dashboard shell. Sidebar navigation, settings screens, and the layout patterns features plug into.
Local infrastructure. Postgres and Valkey in Docker Compose, plus Prisma migrations against them.
CI. Lint, typecheck, and test pipelines that understand the monorepo graph.

Paid provider integrations, including WorkOS auth and Stripe billing, are not part of the free starter. They arrive with the packs that need them.

What the template does not ship

These show up in some other SaaS kits. They are not in the Hype Stack template or packs today:

Capability	Status
Product analytics (PostHog and similar)	Not included. Add your own client if you need funnels.
Feature flags	Not included.
Background jobs / cron runners	Not included as a pack. Use your host's scheduler or a queue you choose.
API rate limiting	Not included in generated apps. See Security.
i18n framework	Not a centered pack. String files may appear in starters for UI copy.

Documenting the absence matters so you do not expect dashboard toggles that are not there.

Getting Started