N+1 leaving

My N+1 just announced his leaving and it's my first time experiencing this

• Updated on August 28, 2025
I've just learned that my n+1 is very soon leaving the company I joined just 2 months ago. 
We are 3 fullstack engineers in something that is not really a startup anymore ( connected 80k connected bikes ), so it feels like a big knowledge, experience repo is leaving the company. 
At the moment, I'm anxious while knowing that this anxiety is over-proportioned compared to the issues his leaving will create. 

It's a funny thing though. 
He's leaving to leave for now software development ( his been in there for 15 years ) for music, and I'm quite happy for him. 
I am happy for him. 
But still I do think about my position in the company, my capacity to provide value for the company. My future in the company and in software development. 
And all these thoughts will amount to not that much except that they slowly change my neuron pathways in tiny increments for which I will have no notion. 
The main thing will be that I will have a bigger sense of ownership/responsabilities when he will be gone. 

In the meantime, the hard job for me will be to find as many unknowns unknowns as I can so they become knowns unknowns and I can ask him about them so they can become known knowns. Pumping knowledge for a practice is tough as well. If I ask you how you make pancakes, most of you wouldnt give me exact figures. I wouldnt. It's something that I've learned to make by the eye and it's normal because it depends on the type of pancakes I want, how many people will eat them and so on. Yet there are some things that I could share, the most important ones, I'm thinking of, is how I failed them. 

Anyhoo, my thoughts of the moments as I learned the person I thought I'd have time to share their experience with so I could bring more value is leaving faster than I thought.