Time Series have an amazing potential for Querying, Parallelisation and Query Composition, because of the nature of the Data itself, this is exactly why general-purpose stores won't ever be the best fit for Time Series data.
Continuum, a Time Series store was built keeping the key features of Time Series data in mind. State-of-art Algebraic structures, can be used to build flexible and composite Query API, Compact data structures can be used to save up space and reduce deserialisation effort while reading data from DB.
An adventure of building a Modern Time Series database in C + Haskell, with ClojureScript front-end, that brings the visibility of everything going on in your system on a whole new level.