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@hackermondev
hackermondev / zendesk.md
Last active November 25, 2025 00:09
1 bug, $50,000+ in bounties, how Zendesk intentionally left a backdoor in hundreds of Fortune 500 companies

hi, i'm daniel. i'm a 15-year-old with some programming experience and i do a little bug hunting in my free time. here's the insane story of how I found a single bug that affected over half of all Fortune 500 companies:

say hello to zendesk

If you've spent some time online, you’ve probably come across Zendesk.

Zendesk is a customer service tool used by some of the world’s top companies. It’s easy to set up: you link it to your company’s support email (like support@company.com), and Zendesk starts managing incoming emails and creating tickets. You can handle these tickets yourself or have a support team do it for you. Zendesk is a billion-dollar company, trusted by big names like Cloudflare.

Personally, I’ve always found it surprising that these massive companies, worth billions, rely on third-party tools like Zendesk instead of building their own in-house ticketing systems.

your weakest link

@raysan5
raysan5 / custom_game_engines_small_study.md
Last active December 2, 2025 17:16
A small state-of-the-art study on custom engines

CUSTOM GAME ENGINES: A Small Study

a_plague_tale

WARNING: Article moved to separate repo to allow users contributions: https://github.com/raysan5/custom_game_engines

A couple of weeks ago I played (and finished) A Plague Tale, a game by Asobo Studio. I was really captivated by the game, not only by the beautiful graphics but also by the story and the locations in the game. I decided to investigate a bit about the game tech and I was surprised to see it was developed with a custom engine by a relatively small studio. I know there are some companies using custom engines but it's very difficult to find a detailed market study with that kind of information curated and updated. So this article.

Nowadays lots of companies choose engines like [Unreal](https:

@romkatv
romkatv / two-line-prompt.zsh
Last active October 9, 2025 19:24
Two-line ZSH prompt
# Example of two-line ZSH prompt with four components.
#
# top-left top-right
# bottom-left bottom-right
#
# Components can be customized by editing set-prompt function.
#
# Installation:
#
# (cd && curl -fsSLO https://gist.githubusercontent.com/romkatv/2a107ef9314f0d5f76563725b42f7cab/raw/two-line-prompt.zsh)
@nadavrot
nadavrot / Matrix.md
Last active December 5, 2025 10:56
Efficient matrix multiplication

High-Performance Matrix Multiplication

This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).

Intro

Matrix multiplication is a mathematical operation that defines the product of

@lattner
lattner / TaskConcurrencyManifesto.md
Last active December 6, 2025 10:37
Swift Concurrency Manifesto
@luckydev
luckydev / gist:b2a6ebe793aeacf50ff15331fb3b519d
Last active October 19, 2025 16:22
Increate max no of open files limit in Ubuntu 16.04/18.04 for Nginx
# maximum capability of system
user@ubuntu:~$ cat /proc/sys/fs/file-max
708444
# available limit
user@ubuntu:~$ ulimit -n
1024
# To increase the available limit to say 200000
user@ubuntu:~$ sudo vim /etc/sysctl.conf
@staltz
staltz / introrx.md
Last active December 1, 2025 11:31
The introduction to Reactive Programming you've been missing
@MohamedAlaa
MohamedAlaa / tmux-cheatsheet.markdown
Last active December 8, 2025 03:35
tmux shortcuts & cheatsheet

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname
@jboner
jboner / latency.txt
Last active December 8, 2025 04:24
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD