Which company should I go with? Offer deadline is in 2-3 days.

A bird in hand is worth two in the bush. Take the offer.

The saying is even more relevant now as it seems like you only have one in the bush.

This job market is still really bad as we can see with the recent waves of mass layoffs. This isn't the economy to be overly optimistic in. Don't take big risks if you can.

Also, it's possible that you can have the best of both worlds:

1. If Company 1 falls through and rescinds your offer prior to start date (this is very possible in this economy) and you get an offer from Company 2, you have that offer as a backup option.
2. If the Company 2 offer is insanely good (far better than Company 1), you can consider reneging Company 1 (keep in mind that you'll probably be blacklisted from Company 1 forever).

The only reason I wouldn't take Company 1 is if their team came across as really toxic, and you can't possibly see yourself working with them. More thoughts on how to identify that here: "How possible is it to spot red flags about toxic culture during the interview?"

Check this out as well: [Masterclass] How To Choose A Good Company And Team As A Software Engineer

I'd take company 1. Pro tip: when a company doesn't give you a firm commitment (e.g. "2 more weeks to interview other candidates too") you should assume that things will be further delayed, so the process may take 4-5 weeks or more.

You really want to avoid a power imbalance where you're desperately praying for a company to get back to you. You need a BATNA.

With that said, you should maintain connection with company 2 over the next few months. Since you mentioned their stock is doing really well, they may continue to hire for 6+ months -- they are an excellent option to join later.

Thanks @Alex and @Rahul for the great answers. I indeed accepted Company 1 today.

Just to expand on this a bit, when manager of Company 2 says he needs to interview further, does that mean I did good but not great to really wow him so that’s why he needs to go interview further? Similar to how we keep interviewing with companies even after getting the first offers because maybe the first couple offers weren’t great deals?

I’m just trying to see what I can learn from this if any to better myself in future interviews.

I wonder if the hiring manager for "Company 2" is interviewing further, does that mean my positive feedback was good but not great?

Every half-decent company knows that in this market, they effectively have a buffet of talent that is chock-full of incredible (and often desperate) laid-off engineers (many of whom are coming from Big Tech). This is the time to get a bargain on the labor of software engineers.

Given that, my guess is that you got "Yes" on most or all of the rounds, and they're looking for a candidate that gets "Strong Yes" on most to all rounds instead.

From running Taro, I have unfortunately seen many engineers get hit by this. They were literally told that they passed every round, but they didn't get the offer as some mega-genius went through the loop and completely crushed it (i.e. "Strong Yes" on every round).