I am writing an api to get data from another api, mix it with some data from a database and then send it back.
I am using nodejs (javascript) to write it but I would like to learn something new. Can you recommend me any languages that I could use for my backend? I was thinking maybe go but I am open for ideas.

Feel adventurous enough to try haskell? The snap framework is very relaxing to work with.

@BindView I was actually thinking about haskell, I may even try it but I would like to wait for other recommendations :D

asp.net core .. didn't use it myself yet, but based on asp.net it'll be nice and boring :D

Go, gets you started very easily.The the concurrency model is very nice and accomodating
Go has nice libraries that build up in the standard library
But I'm also leaning towards the adventurous Haskell if you wanna have a go at a new language

@byte I think I will go with go (haskell maybe later :D), can you recommend me any resources to get started?

Any other recommendations? :)

@hash-table yeah I really like js but I would like to learn something new :D

@404response the standard library has the basic things already
To build up on it gorilla has some nice improvements
There are framework available, like gin, martini, etc.

For learning and starting use standard with gorilla libs, as framework can be overkill
Gorilla is the community default, many blogs and examples will be available
I've use it and recommend it

I just finished writing an API in Python using the minimal http framework Flask. I can really recommend it, I truly enjoyed it.

I deployed to Heroku for free and with the addons they provide I now have metrics, alerts and a logging aggregator with minimal to no effort on my side to set it up. Such a smooth experience. I love Heroku.

Aws serverless infrastructure is really cool and free for the first year, really recommend you to try it out!
Api gateway -> lambda -> dynamodb. If you are looking for a faster and less complex api try out express.js. Only takes a few minutes to be up and running!