Harper

Founded 2017

Run database, caching, APIs, and real-time messaging inside a single backend runtime

Pricing model

Free Tier, Paid

You can use Harper to build and run backend applications, APIs, and AI agents inside a single process. Instead of managing separate databases, caches, message brokers, and web servers, it combines structured data storage, in-memory caching, real-time pub/sub messaging, and vector search into one environment. You define your data models with GraphQL schemas to automatically generate REST and GraphQL endpoints. Harper handles background replication across edge locations, executes custom business logic next to your data, and serves API requests with sub-millisecond retrieval speeds.

What Harper does

Define database tables using GraphQL schema syntaxQuery and filter records using URL parameters or GraphQL queriesSubscribe to live database record changes using Server-Sent EventsCreate vector embeddings automatically on record creationDeploy backend logic and database configurations across multiple edge locationsExtend database tables with custom JavaScript classes for validation and business logicCache responses from upstream ERP or pricing services with custom expiration timesRuns database, caching, messaging, and application logic in a single processAuto-generates REST and GraphQL endpoints directly from GraphQL schemasProvides built-in vector search and indexing alongside structured dataIncludes native pub/sub streaming over WebSockets, Server-Sent Events, and MQTTReplicates data globally across distributed edge locationsExecutes custom JavaScript business logic directly next to stored dataCaches external API responses with automatic cache stampede protection