I am a software engineer and looking for the next step on my career. I had a first interview with company A and they are keen on going to next steps. They also told me that I will work for another company's project without naming the other company and they told me the salary budget is up to X. Then I had a call with company B, they also told me they like my profile and they give me about X to X +200$ net per month. And now the surprise. I found out in the assessment of company B that it will get checked from the Tech lead of company A.
Both of them seem pretty good. What should I consider to decide how to proceed?