Riddle:

Alice and bob want to communicate a secret message, lets say it is an integer.
We will call this msg0.
You are Chuck, an interloper trying to spy on them and decode the message.

For keys, alice chooses a random integer w, another for x, and another for y. she also calculates a fourth variable, x+y = z
Bob follows the same procedure.

Suppose the numbers are too large to bruteforce.

Their exchange looks like this.
At step 1, alice calculates the following:

msg1 = alice.z+alice.w+msg0
she sends this message over the internet to bob.
the value of msg1 is 20838

then for our second step of the process, bob calculates msg2 = bob.z+bob.w+msg1
msg2 equals 32521
he then sends msg2 to alice, and again, you intercept and observe.

at step three, alice recieves bob's message, and calculates the following: msg3 = msg2-(alice.x+alice.w+msg0)
msg3 equals 19249. Alice sends this to bob.

bob calculates msg4 = msg3-(bob.x+bob.w)
msg4 equals 11000.
he sends msg4 to alice

at this stage, alice calculates ms5.
msg5 = (msg4-(alice.y)+msg0.
alice sends this to bob.

bob recieves this final message and calculates
the sixth and final message, which is the original hidden msg0 alice wanted to send:
msg6 = msg5-bob.y

What is the secret message?
I'll give anyone who solves it without bruteforcing, a free cookie.

I'm currently between jobs and have a few rants about my previous job (naturally). In retrospect, it's somewhat therapeutic to range about the sheer brainfuckery that has taken place. Enjoy!

First, let me set the scene: legacy B2B web app made with LEMP stack and sencha ext.js 3 + 4 (don't ask) and a lot of madness. Let's call that app "Alpha".

Alpha is a self made CMS build for typical ERP stuff. Yes, a self made CMS: entities are containers, containers have types and fields and values. Like so many legacy PHP apps, it does not have a dedicated FE: the HTML is rendered on the server and then spewed out to the browser.

Easy right? Coding like it's 1999! But there was a twist: Because everything is basically a container, the HTML-templates are saved in the DB. Along with the nessary JS and the CSS. And the translation variables. Why? Because fuck you! That's why. Who needs a git history anyways.

For some reason, Alpha was kinda slow.

There was also an editor, that allowed you to modify templates (web, mail, pdf) on the fly in prod. Because templates contain repeating data (header/footer), one template could contain additional templates. Much confusion. You could change templates via migration (slow, boring) or just ctrl-c/ctrl-v that sucker (fast, much excitement).

Did I mention Alpha was slow?

On with the rant: e-mails! How do they work? Noone knows. How to send mails asynchronous in PHP? Witchcraft is the only possible answer to that riddle. Here is your enterprise™ solution:
1. create mail
2. insert mail into DB
3. WAIT UP TO 59 SECONDS FOR A FUCKING CRON TO SEND MAIL

Why? "Because that way, we can resend mails in case the network is down :)"

Same procedure for the SOAP-API (db-queue + cron). You read that right: all requests to various other systems are processed once a minute.

Alpha slow.

Alpha was only one of several systems. Imagine a bunch of monolithic php apps, interconnected via SOAP, REST and GraphQL like a godamn intergalactic orgy. Image having to debug that cluster fuck.

Let's say there is a bad request. These things happen. No biggie. Remember the db-queue? Let's try to send the bad request a second time! And a third time! Still no luck? How odd. Let's create a specific file in a specific directory: a LOCK-file. Now, "the db-queue is on hold and no request gets processed :)"

Golly gee thanks Alpha.

Anyhow, did you know that MySQL has a join limit of 61 tables?