# altengine

> altengine revives Google App Engine's retired Search and Channel APIs as simple, drop-in cloud services. It offers managed full-text search and realtime message channels with API contracts faithful to the originals, a genuinely free tier on every service, and usage-based pricing beyond it. altengine starts with App Engine revivals but is not limited to them — the platform is built to add new managed services as demand grows. altengine is an independent project and is not affiliated with Google.

## Services

- Search API: managed full-text search. Structured documents (text, atom, number, date fields), a query language faithful to App Engine's Search syntax, facets, sorting, and pagination. Billed on queries and on storage for documents and their index (index storage counts only the document content you push, so it stays cheap); there is no charge for idle capacity (no cluster to keep running).
- Channel API: realtime pub/sub. Subscribe-only client WebSockets (one socket carries many channels) authenticated with short-lived, channel-scoped tokens; HTTP publish; fan-out to subscribers. Clients open and manage their own WebSocket connection. Billed on message deliveries and connection time; a channel with no open connections costs nothing.

## Pricing

One plan: pay-as-you-go. The first US$1.00 of usage each month is free for every organization; you pay only the amount above a dollar. Rates: Search queries $0.50 per 1,000; Search document storage $1.00 per GB-month; Search index storage $2.00 per GB-month; Channel message deliveries $2.50 per million; Channel connection time $0.02 per million connection-seconds. Indexing is billed as index storage (the per-GB-month rate above), counting only the document content you push; there is no charge for idle capacity. No tiers, seats, or minimums; no credit card required to start.

## Pages

- [Home](https://altengine.net/): Overview of altengine and its two launch services.
- [API documentation](https://altengine.net/docs): Base URL, authentication, grant levels, quickstart, and errors for the Search and Channel APIs.
- [Search API reference](https://altengine.net/docs/search): Documents, field types, the query language, facets, sorting, and pagination.
- [Channel API reference](https://altengine.net/docs/channel): Subscriber tokens, HTTP publish, and WebSocket subscribe with live channel control.
- [Pricing](https://altengine.net/pricing): Free tier allowances and usage-based rates for Search and Channel.
- [About](https://altengine.net/about): Why we're reviving App Engine's APIs and the principles behind the build.
- [Blog](https://altengine.net/blog): Announcements, engineering notes, and migration guides.

## Posts

- [Announcing altengine](https://altengine.net/blog/announcing-altengine): Launch announcement covering both APIs, the design principles, pricing, and how to migrate from App Engine.

## Legal

- [Terms of Service](https://altengine.net/terms)
- [Privacy Policy](https://altengine.net/privacy)

## Getting started

1. Create an organization in the console at https://console.altengine.net
2. Generate an API key with a grant for Search, Channel, or both.
3. Point an existing App Engine Search/Channel client at altengine's base URL and credentials.