How hard is it to build something new while under a non-compete? I understand you can find new areas to work in, but I imagine you'd think back to previous wor

How hard is it to build something new while under a non-compete? I understand you can find new areas to work in, but I imagine you'd think back to previous work and be tempted to make connections to that field, or use some of what you built previously in the new context. Is it difficult, or is it just a completely separate problem space?