Timezones. So, general rules are:

1. If you don't store timezone, always use and assume UTC. Databases, backends, whatever you use, all time must be kept be in UTC.
2. If you store timezones, ensure you store them everywhere and don't drop them anywhere.
3. It's always better to ignore backend server time in favor of database's `now().` Having a single source of truth makes time consistent (if it's the same database, obviously). If you combine backend time and database time, you likely get a violation of causality.

I've just spent a couple of hours investigating "weird random one-hour time drifts on updates." Guys violated all three rules above:
- they didn't store the timezone;
- their servers had inconsistent timezones. Java was in +XX., while the server itself in UTC. On one host, they forgot to put JVM in the same timezone;
- they dropped the timezone because they thought it was the same everywhere, so there was no point in serializing it.

When your internal timezone automatically changes over the weekend and you have to get it back to "normal" but then somehow end up not sleeping at all 😅😐😑😪

My preferred stack is Rails/NginX/Postgres, or Node using the same.

I have a fair amount of material for this week's rant, but in my stack's defense, the quantity is primarily because I've been using it for so long, and I'm apparently a talented breaker. I may share other stories if the motivation arises.

However, today I ran into something definitely deserving of calling out.

The default datatype for a Date+Time column in Postgres is `datetime` which means "date+time without timezone". (while `datetimetz` instead stores the timezone).

Apparently when comparing a datetime with a datetimetz, Postgres doesn't compute the timezone difference correctly, leading to some very unexpected and confusing query results.

Today, I had a record that was both pending (expires_at > now) and expired (expires_at <= now), where now is a DateTime (with tz) literal from Rails. After half an hour's frustrated delving and baffled expressions at query results, I finally figured out that the database's math was incorrect when comparing UTC (+0) and PST (-7).

This during a semi-high-priority bugfix that's blocking for a coworker.

While Time and all of its nuances are honestly extremely difficult to handle correctly, I didn't expect Postgres to get this relatively simple part wrong.

Shame on you, Postgres.
I expected better.

I've been wondering about renting a new VPS to get all my websites sorted out again. I am tired of shared hosting and I am able to manage it as I've been in the past.

With so many great people here, I was trying to put together some of the best practices and resources on how to handle the setup and configuration of a new machine, and I hope this post may help someone while trying to gather the best know-how in the comments. Don't be scared by the lengthy post, please.

The following tips are mainly from @Condor, @Noob, @Linuxxx and some other were gathered in the webz. Thanks for @Linux for recommending me Vultr VPS. I would appreciate further feedback from the community on how to improve this and/or change anything that may seem incorrect or should be done in better way.

1. Clean install CentOS 7 or Ubuntu (I am used to both, do you recommend more? Why?)
2. Install existing updates
3. Disable root login
4. Disable password for ssh
5. RSA key login with strong passwords/passphrases
6. Set correct locale and correct timezone (if different from default)
7. Close all ports
8. Disable and delete unneeded services
9. Install CSF
10. Install knockd (is it worth it at all? Isn't it security through obscurity?)
11. Install Fail2Ban (worth to install side by side with CSF? If not, why?)
12. Install ufw firewall (or keep with CSF/Fail2Ban? Why?)
13. Install rkhunter
14. Install anti-rootkit software (side by side with rkhunter?) (SELinux or AppArmor? Why?)
15. Enable Nginx/CSF rate limiting against SYN attacks
16. For a server to be public, is an IDS / IPS recommended? If so, which and why?
17. Log Injection Attacks in Application Layer - I should keep an eye on them. Is there any tool to help scanning?

If I want to have a server that serves multiple websites, would you add/change anything to the following?
18. Install Docker and manage separate instances with a Dockerfile powered base image with the following? Or should I keep all the servers in one main installation?
19. Install Nginx
20. Install PHP-FPM
21. Install PHP7
22. Install Memcached
23. Install MariaDB
24. Install phpMyAdmin (On specific port? Any recommendations here?)

I am sorry if this is somewhat lengthy, but I hope it may get better and be a good starting guide for a new server setup (eventually become a repo). Feel free to contribute in the comments.

Feel like shit, can't focus on work, exam coming up in about 2 weeks...
These stupid numerical algorithms are easy, and yet I manage to get stuck on every shitty little detail, I panic, and I completely lose focus.

This shit has been destroying my academic career... Can't focus properly anymore, cannot study even the simplest things - things that I used to do off the top of my head just a year ago.

My sleep schedule is FUBAR, it's a miracle if I manage to stick to the same timezone for three nights in a row.

Yet I'm still learning new things, trying out stuff and solving problems. Just not the ones that I need to pass my exams.
And before anyone says that university is useless and whatnot: I'm studying aerospace engineering.
I love it, I'm having great fun, learning amazing things, and I've met a lot of amazing people thanks to it. It's one of the few choices in life that I am certain of, and would gladly repeat over and over again.

I've burned myself out from stress, far harder and longer than I've ever done before, and I cannot figure out a way to recover from it.
I've been doing better in the last month or so, but I still cannot get any proper work done, and this is gonna bite me in the ass really hard, once again.

Funny story: I had 3 days of break between the end of the previous semester and the beginning of this one. 3 days of pure freedom.
In those 3 days, I spontaneously reverted to a normal sleep schedule (didn't even need an alarm clock) and felt like a mountain had been lifted off my shoulders.

A year ago I had no idea what truly panicking in the middle of an exam felt like.
My mind had never gone completely blank.
I had no idea what impaired cognitive ability felt like.
This shit is scary.

Why do our minds have to make things so complicated?