The definitive source of the best
JavaScript libraries, frameworks, and plugins.

  • ×

    Impressive totalitarian style Multipurpose Application Server for node.js. All decisions are made. Solutions are scaled. Tools are provided and optimized for high load. Ready for applied development and production.
    Filed under  › 

    • 🔾39%Overall
    • 543
    • 22 hours
    • 🕩72
    • 👥3

    impress logo

    travis codacy npm version npm downloads/month npm downloads license

    Impress Application Server for node.js. All decisions are made. Solutions are scaled and optimized for performance and load.

    Metarhia and Impress Application Server way:

    • Applied code need to be simple and secure, so we use code sandboxing with v8 isolated contexts and worker threads;
    • Domain code need to be separated from system code; so we use layered architecture and contract-based approach;
    • Impress supports both stateful applications with RPC and client-session sticky to servers;
    • No I/O is faster even then async I/O, so we hold state in memory and use lazy I/O for persistent storage;


    • Auto API routing, just create endpoint files as an async js lambda function;
    • API code live reload with file system watch (when files changes on disk);
    • Graceful shutdown and application state recovery after reload;
    • Minimum code size and dependencies;
    • Can scale on multiple threads and servers;
    • Code sandboxing for security, dependency injection and context isolation;
    • Utilize multiple CPU cores and serve multiple ports with worker threads;
    • Inter-process communication and shared memory used for state management;
    • State synchronization mechanism with transactions and subscription;
    • Cache server-side executable JavaScript in memory;
    • API development support: AJAX RPC and Websocket support;
    • Serve static files from memory cache;
    • Application configuration (for different named environments);
    • Database access layer for PostgreSQL and Relational db schemas;
    • Persistent sessions support with authentication, groups and anonymous;
    • Multiple protocols: HTTP, HTTPS, WS, WSS;
    • Logging with buffering (lazy write) and rotation (keep logs N days);
    • File utilities: upload, download, streaming;
    • Built-in simple testing framework;
    • Server health monitoring;
    • Built-in data structures validation and preprocessing library;
    • Task scheduling (interval or certain time);
    • Request queue with timeout and size;
    • Execution timeout and error handling;

    Installation, upgrade and start

    • Install with npm install impress
    • See project structure Metarhia Starter Kit
    • Start server with npm run start or node server.js
    • To select execution mode (test, dev, prod) use MODE=dev node server.js


    • Node.js v12.9.0 or later (v14 preferred)
    • Linux (tested on Fedora 30, Ubuntu 16, 18, 19 and 20, CentOS 7 and 8)
    • Postgresql 9.5 or later (v11.8 preferred)
    • OpenSSL v1.1.1 or later (optional, for https & wss)
    • certbot (recommended but optional)



    Copyright (c) 2012-2020 Metarhia contributors. Impress Application Server is MIT licensed. Project coordinator: <>

    Show All