I've never worked in any company that was able to fill any position
faster than 2.5 months. Everyone clamored that we needed to fill positions fast, but then endless, nauseating political debates about minutiae on resumes and tiny flaws during in-person interviews took over, and it would just drag on.
I once was taken almost completely away from my engineering duties for a period of a whole month to help almost full time with what was a "critical" position that needed to be filled "now". A year and half later, when I decided to leave that company, they still had not hired for that position, and had an endless list of why every candidates didn't make the cut (and we had interviewed some excellent candidates who got thumbs up from all of the technical staff who had interviewed them).
It's different everywhere, but in general for a competent tech worker with about 3+ years of experience, I'd say you're looking at at least 6 months to find someone, probably closer to a year, not because there fails to be a supply of good candidates, but because that's just the time penalty for internal politics.
While this particular anecdote happened at an established firm, I experienced nearly the exact same thing in start-ups as well, literally the same political bullshit excuses used to reject otherwise great candidates even when we were "desperate" to hire someone.