The One Pot Application (OPA) from MLState is a complete development platform for web applications and services:
Development in OPA requires no plumbing. Applications developed with OPA are automatically checked for safety and security before they are executed. Applications developed with OPA are automatically (and provably) immune to cross-site scripting, to SQL injections and to most existing forms of attacks. And OPA provides language support for storage, communication between client and server (Ajax and Comet), concurrency, distribution, mobility, etc.