Neil Jedrzejewski

RWASA - A high performance, scalable web server written entirely in assembly.

Blog Post created by Neil Jedrzejewski Employee on Jul 27, 2015

I happened upon news of rwasa - Rapid Web Application Server (in Assembler) this morning and was interested by it's performance approach being written entirely in x86_64 assembly language.


It touts itself as being particularly good for high-volume sites that require low latency which immediately made me think of a number of customers I work with running JSON API/services. They need to ship vast volumes of JSON response slugs as quickly as possible as part of web site frameworks.


Sadly I don't manage infrastructure these days but would be interested to know if anyone is planning on giving it a go, especially if you're an existing nginx user.


Noted features:


  • Open source/GPLv3
  • Entirety hand-written in x86_64 assembly language
  • Faster than nginx for most environments
  • Commercial support available
  • TLS auto-blacklisting for anti-tampering
  • OCSP Stapling by default
  • Randomized Diffie-Hellman safe prime pool
  • Multi-process lockless TLS session resumption cache
  • TLS session cache is encrypted by default
  • Faster dynamic content compression
  • Large-scale FastCGI safely via unix sockets (without hitting EAGAIN)
  • Large-scale backpath (aka upstream) safely via unix sockets
  • Simple command-line arguments covers all common configurations
  • Small footprint, no external dependencies
  • Server-side BREACH mitigation (randomized headers, see notes)
  • HSTS enabled by default


Didn't see any mention of HTTP/2