Ask HN: Recommended services/teams doing pen testing

For a product we have build, we want to go through a penetration test (not just an automatic vulnerability scan).

Would like to get some kind of certificate for that as it may be needed in the future. I have went through (listed below) similar questions on HN, there are some options proposed, but as people change, maybe there will be something better this time.

If someone wants to recommend in private, can find an email on my profile :)

Listing previous similar discussions for the next guy:

[1] https://news.ycombinator.com/item?id=23998656 [2] https://news.ycombinator.com/item?id=20769139 [3] https://news.ycombinator.com/item?id=10813074 [4] https://news.ycombinator.com/item?id=7789916 [5] https://news.ycombinator.com/item?id=6675074