Hi, thanks! It took me over six months to finish it and as always with my ideas seems like market for it is too small, at least currently.

Data is available since 2019-03-30 for majority of the supported exchanges. Yes it's all from public APIs.

I can imagine , as a tech stack , you must be using ccxt , nodejs and some Timeseries database ? Also what all distinct "channels" you are saving ?

No it's all custom stuff written from scratch, some in .NET Core, some in JavaScript (Cloudflare workers, Node.js client libs). I'm saving to flat files on Google Cloud Storage and Wasabi (S3 compatible alternative), given TBs of data it's much cheaper. Filtering is being done on demand. Regarding channels that heavily depends on exchange, you can use https://tardis.dev/api/v1/exchanges/:exchange API to get the list (eg. https://tardis.dev/api/v1/exchanges/bitmex)