andreyka26_se
607 subscribers
587 photos
66 videos
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298 links
Hey, I'm software engineer at Microsoft, with 7 years of experience. Here we are talking about F(M)AANG big tech interviews: leetcode, system design and corpo life.

YouTube: @andreyka26_se
Instagram: andreyka26_se
TikTok: @andreyka26__
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CAN YOU FUCKING IMAGINE, chrome does not show "preview" or "content" of the page that was before redirection, but Edge does show it?

(yes, still trying to understand this phishing site)

https://superuser.com/questions/1788537/why-do-chromes-developer-tools-fail-to-always-collect-response-data
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YES, I FUCKING FOUND IT, I FUCKING FOUND IT.

KUDOS to Andrey, who helped to learn new concept called web workers.

Will post detailed analysis later
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Let me start.

Whenever you click on the "vote", the telegram page loads.

STEP 1. telegram-page.html (naming for simplicity, actually named "/pnbZeA4")

This telegram page is regular "document" request that loads bunch of js files:
- 4vt095smidla.js.
See screen 1.

STEP 2. telegram-client-preloader.js (actually named "/4vt095smidla.js")

This preloader loads telegram client loader and bunch of other .js files

See screen 2.

STEP 3. telegram-webworker-loader.js (actually named "/9nnoq789wklc.js").

This loader registers WebWorker that runs telegram client js. This webworker runs in separate thread so we actually don't see opened sockets to Telegram.
See screen 3

STEP 4 telegram-client-webworker.js (actually named "/vmu7hv3hxb8g.js") starts communication with telegram using websockets.
To see it in webtools, go to edge://inspect/#workers, and click "inspect" on all workers you will see

See screen 4, 5, 6

Attaching deobfuscated files (some of them are so large that I need to do it locally)
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From now on, as they are changing domains the next day after my report - I will be posting domains to report here, so please join me, and let's ban motherfuckers, or at least make them pay for domains. For you it will be few clicks I will leave report content and links
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Daily (111 day streak)

Everyone in discussion is keep saying it is hard, but I got stuck in understanding how to understand the node is leaf, or node is root, or node in the middle.
I will give you hint: the node is leaf in graph only in case it has single connection and this connection is parent. Otherwise problem is not that hard (check hints in leetcode)

https://leetcode.com/problems/maximum-number-of-k-divisible-components/description/?envType=daily-question&envId=2025-11-28

#daily #hard
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Daily (113 day streak)

Actually I would say intuition here to build is pretty hard. But once you have it solution is not that cumbersome or hard

https://leetcode.com/problems/make-sum-divisible-by-p/description/?envType=daily-question&envId=2025-11-30

#daily #medium
Daily (114 day streak)

Hard, and it is hard, especially to build an intuition. But in the comments I will leave the hints that helped me to build mental model

https://leetcode.com/problems/maximum-running-time-of-n-computers/description/?envType=daily-question&envId=2025-12-01

#daily #hard
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Daily (115 day streak)

Nice problem. I found out that I really like when leetcode problem has something physical or semi physical. Today it is geometry and trapezoids. However some simple math is used here.


https://leetcode.com/problems/count-number-of-trapezoids-i/description/?envType=daily-question&envId=2025-12-02


#daily #medium
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After 1 month of procrastinating and writing in background, it is eventually out. I guess this is the most detailed article about Stripe System Design.

Please leave your thoughts about the decisions made in the design and overall about the article.

https://andreyka26.com/payment-gateway-stripe-system-design-with-microsoft-engineer
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