It’s a team of 45 people with half of them engineers.
What tips or suggestions have you found to form part of a first 90 days of a CTO role?
What are the expectations? What outcomes? What activities?
After two years as a CTO I found that the most important part of my work was to have the right developers for the job. You personally cannot know every technical detail, your 20 developers have to deal with every day. So they have to be experienced to know it mostly by themselves.
In your case I would start with personal interviews with every developer to identify their experience in certain technologies and also to get to know their desires for the next 2-3 years. This will help you to focus on the right candidates in the recruiting process.