After working with different companies, I've established two different types of opportunities to work with me:
Short Term/High Intensity: Audit
Situation You're in a tough position. Your users are seeing 500s, your metrics don't make sense (or don't exist), but your traffic keeps growing. This is a good problem to have, but its still a problem.
Solution Given access to your team, code, and tools, we can come in and do a full top to bottom audit of your current performance problems. Depending on the size of your application this can range from two days to two weeks. The end result of the work is a mutual understanding of the state of your app. This includes comprehensive (and comprehensible) metrics and a prioritized recommendation of lowest-hanging fruit and next steps that you and your team can execute to get to the next level.
Long Term/Low Intensity: Coaching
Situation You're growing quickly and you and your team are spending the majority of your time supporting your users by creating features and don't have much time to spend on growing your infrastructure or improving the performance of your app. You feel like you're in a good place at the moment, but can see a point on the near horizon where your current setup is going to show cracks.
Solution Starting with some in-depth looks around your code and infrastructure we'll come up with some high priority issues to tackle together. Then on a regular schedule (once a week or once a month) we'll spend a day revisiting this plan, addressing new issues, and talking through the future.