I'd make sure my grandpa ended up in jail, instead of getting away with what he did.

I'd do a lot more exercise, and take far better care of myself. I'd push as much money into savings and investments as I could.

If the market works the same way, I'd have a boatload of stock and Bitcoin by now, and I would know who Satoshi really is/was.

If the market doesn't work the same way, no big deal. I know a lot more about how business really works, and how to manage people, so I'll do ok with my career.

I'd try to push things on the internet towards a better outcome. It's before eternal September, so there is hope. I'd try to get emails signed by the sending server. I'd push capability based security, open source software, and make non-ad funded social networks a thing.

* Tell the girl I had a longtime crush on that I was still into her. (Got rejected, then after a bit we dated, now we are married with a kid).

* Hangouts with friends playing D&D.

* Hangouts with friends sipping whiskey and talking about life and the world.

* Meaningful conversations with people I admired.

* Traveling Europe/Asia with my girlfriend.

Things I would do differently:

* Watch less TV/movies.

* Drink less at bars

* Spend less time arguing with stupid people on the internet

* I should have looked for a well paying job sooner. If i'm not going to love my job, I might as well maximize my returns. I saved a decent amount but I probably could have been making an extra 30k a year 5-10 years earlier. Investing half of that would have meant even more financial security now.

People who are richer and more successful are not always better. Most were lucky. You have to trust in yourself more than you trust others. In fact, nearly all my failures in my early 30s/late 20s have been trusting someone who went to MIT or someone with a history of success.

Don't bother with practical productivity books. Nothing stuck. Anything that tells you that doing X will give Y results is lying. History books are fine: someone did X and Y happened. Psychology/science is fine: statistically Y happens as a result of X. There's a subtle difference, but basically a practical book is very fragile. It's like memorising chess openings; the tools work in very specific conditions. The difference is that the world changes quickly - everything in Rich Dad, Poor Dad or the 4 Hour Workweek becomes an anti-pattern once the world changes.

"Resume items" won't land that job or even a better paycheck. Just optimize to do good work, not looking good on a piece of paper.

Though, I suspect that a side effect of taking good general advice from those more experienced than you is that you might miss out on, or never learn to identify exceptional specific advice that few are able to provide.

Since starting a business is a common topic I see in these threads across the internet, my two cents: 27 for me is just flipping the calendar back. I started a business in my late 20s. I still should have done it sooner.

But, I believe there's a threshold. You need the experience to do the business, but you still want to be in a place where you don't have enough experience to get up and run the business when you start without doing some homework along the way: I don't think you want to be figuring out LLC paperwork, general liability, and payroll in your 30s.

You can do all of that in your early 20s, and if I were to give advice to my younger self, do it before you turn 25. As young as possible, even if you're still in high school and keep working full-time jobs as an employee into your 20s for household cash safety, stuffing away as much as you can.

I think the latter owner of Designer News started his ventures at 18 and mentioned to members there that his progression simply looked like delegating more and more to others until he got where he was.

In general, I think these threads are useful to young people, but they're not a source of exceptional advice.

They're a source of good foundational advice like spend time with your family, don't spend beyond your means, save, work hard.

- Forget about seeking a 'safe' job. Go find a startup to join. Don't worry about having to sleep on someone's couch.

- Save more.

- Go ahead and get that master's degree. It's pretty hard when you're married and have kids.

- Get into better shape and stay that way. At 40 losing weight is so much harder than it was back then.

Now you have a nice cushion to take risks and a wide open field to do so.

2. Do everything possible to get into FAANG or other top tier tech company. Made the ignorant mistake of thinking that working in the tech departments of Wall Street investment banks and hedge funds were the pinnacle of a SWE career (I'm not referring to places like Citadel/TwoSigma/JaneStreet/etc.etc.). Ignorance is bliss. Note that this was many, many years ago when a SWE career wasn't considered as hot as it is today; plus I was surrounded by Wall Street finance types in my social circle, as opposed to fellow SWEs/technologists.

3. Related to #2, but probably move out of NYC to the SFBA.

Even before retirement age you can make penalty-free withdrawals for health emergencies and first-home purchases. (And if your salary is low now, you can pay the taxes now for a Roth IRA, making all the withdrawals tax free.)

Other than that, I’d be kinder to myself and ask for help more. I’d try to be nicer to other people, too.

But all the major stuff I would keep the same.

Actually it's my greatest regret of all time.

If I could get back in time, I would have traveled back in my teen years with videos and photos to prove my failing future so I could convince myself to take things lightly and just live without caring about tomorrow.

Just find any job to make a living and enjoy your life; don't be harsh to yourself, it's not worth it.

Technology lost its spark for me; I use it only for leisure, nothing more.

- I would save and invest a lot more than I did. In my case, I would have an additional 500K-700K easily if I just saved when I was 27. I am almost 40 now. This is without compounding. Kids, don't waste all your disposable income. I was making six figures in my mid 20s and had no obligation except some student loans and I blew money like crazy (Bought BMWs etc). I don't regret all of it but I should have saved more. Don't be me.

- Start a business. I always wanted to do my own thing but by the time I pulled the trigger, I was 33. I regret that. A LOT.

- Spend more time with people who love you and care about you. Don't wait for one fine day. They may be gone before you know it.

- Take better care of my body than I did. I am trying to fix it now but at 27, I could have done so much more.

Oh, and AAPL also, but that didn't occur to me at the time.

I'll then invest in an indie retro studio regardless of it being successful or not. Or maybe just see if I can get into Nightdrive.

Family side wouldn't change much. Maybe would get the baby a few years earlier.

Now age 18-27 I would love to redo. Help my wife get therapy sooner.

- I would NEVER accept that job offer

- I would leave the country (I'm not from the United States)

Start leaning how to invest money. Savings account is not an investment.

Read those books I bought and never read.

Watch out for smartphone addiction.