The thing about past work is that it stays done

I don't think the cure is to talk yourself out of the doubt. The doubt is partly information; it tells you the next thing is genuinely uncertain. What I've found more useful is a small structural observation that takes about ten seconds to internalise but rewires the whole calculation.

Past achievement is a fact in the world. Nobody can take it back. The shipped system is shipped. The team you built is built. The talk you gave is recorded. The decision you got right is part of the historical record now. None of that depends on whether you nail the next thing.

That sounds obvious when you write it down. It is not obvious in the moment. In the moment, the next deliverable feels like a referendum on everything you've done before - as if a stumble would retroactively unmake the years that built up to it. It wouldn't. The future doesn't have an undo button on the past.

I find it helpful, when the new thing looks intimidating, to write down three concrete pieces of work I'm proud of. Not awards or titles - actual artefacts. A document, a launch, a hire, a fix. The list is usually longer than I expect, and it cools the imposter signal enough to start the next thing.

Wishing you a quiet end to 2024 and a good start to whatever comes next.