diefans

I suggest you use only aiohttp and for your postgres part use https://github.com/aio-libs/aiopg. There is also https://github.com/RazerM/sqlalchemy_aio wich wraps sqlalchemy into threads to achieve async abilities.

The drawbacks of AIOHTTP are that you only use one stack instead of two (+Tornado) which leads in the end to less confusion about your architecture ;)