Have you worked at multiple jobs over those 10 years? As a hiring manager (working with only the limited data you've provided here) I'd be concerned that you value stability very highly, and you might be thrown by the rate of change (in requirements, tools used, business goals, desired feature set, etc) that is typical of a startup. Long tenure at a single job suggests you enjoy getting deeply specialized and developing mastery of a stable set of tools, which is needed at a certain stage of company but not at most early-stage startups.
Is that true of you? I.e. would you be frustrated by 3-4x/year significant churn in your technological tooling and top-level business goals? Would you be excited to learn a few new toolsets? If so, why haven't you done that on your own?
Wow. Really? Why is stability a concern? Much of engineering is making solid decisions and fucking sticking with them rather than changing to the latest toolset because that's what hacker news says is the best today. Are you trying to build a product and company, or a blog post?
Stability is a concern because startups are not stable. In 6 months time Apple could open source something that makes your last 5 years of work irrelevant in a night. If you can't ship in 6 months you're company will probably have shut up shop in 12 because someone already ate your lunch.
If it's a choice between stability (via proper testing, architecture, etc.) and staying operating, stability loses every time.
No matter what happens the tech world is a different place in a year. You have to adapt regardless so properly thought out code will get thrown out just as easily as 4am hacks.
"Would you be excited to learn a few new toolsets?"
I suspect by the 3rd or 4th time in the same year with people who haven't worked out what it is they are trying to achieve my level of excitement might be wearing a bit thin.
Is that true of you? I.e. would you be frustrated by 3-4x/year significant churn in your technological tooling and top-level business goals? Would you be excited to learn a few new toolsets? If so, why haven't you done that on your own?