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GeeTest CAPTCHA Bypass: How to Solve a Sophisticated Anti-Bot System

Level of difficultyEasy
Reading time13 min
Views312

One could write, “Experienced developers working on parsing and automation often face the need to bypass modern CAPTCHAs.” But that’s too boring… I’d rather start like this—continuing to explore the amusing world of CAPTCHAs, I finally stumbled upon the Chinese variant of protection: the GeeTest CAPTCHA. Let’s break down what this beast is, where it dwells, and why you should (or shouldn’t) fear it… You’ll understand as we go!

GeeTest is one of the advanced anti-bot systems combining user puzzles with behavioral analysis. I decided to take a close look at recognizing the GeeTest CAPTCHA under real-world conditions and figure out how to bypass GeeTest with various methods. But first—a classic introduction (which, by the way, may be more interesting than the practical part of the article, since bypassing the GeeTest CAPTCHA is already a non-trivial task for many readers).

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Yandex huge privacy issue or not?

Reading time2 min
Views576

Hi to everyone!

I'm new here. Someone told me that Habr is like russian reddit for developers (and maybe not). And I'm here today to share my story and get opinions from you, part of this community.

In August 2024 I visited Moscow, and got Russian starter pack, even if foregneir :-)
Will be useful later because I'm moving here, Русский язык coming soon, извините!

So let's start with getting a new bank account, make a new mobile number and start to register to some essential service platforms like Metro, Gorod, ВВ, Perekrostak and Yandex for delivery and taxis. And in every service I found something strange. A certain "Ivan" (I've changed the name for privacy) is present in all my accounts where I try to register.
That's it! The phone number that my bank gave me was just.... recyled! So I could start to get personal data through all these existing account on this new phone number of mine but the most shocking thing occured today!

Alarm on 9:00, I woke up and I got a message by Yandex:

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Horsehead Nebula

Level of difficultyEasy
Reading time6 min
Views294

The whimsical image of a chess knight in profile among the stars is perhaps the most recognizable among deep space objects. It can be said that the Horsehead Nebula tops the recognition rankings among nebulae and galaxies. Perhaps the Andromeda and Orion Nebulae resonate more with the general public, but only specialists and advanced amateurs know what they look like. Even among them, there are often cases when the famous Andromeda Galaxy is confused with another galaxy, even by experienced popularizers of astronomy. The Orion Nebula, too, can look different in pictures taken with various filters. Yet, the profile of the chess knight allows every inhabitant of Earth to recognize that in front of them is the one-of-a-kind and completely unique Horsehead Nebula.

Let's begin by noting that when we talk about the Horsehead Nebula, we refer to two fundamentally different formations in this region of our Galaxy. Only together do they create this memorable visual image. Moreover, what we see—the glowing diffuse background—is not the Horsehead Nebula. It is a dark silhouette against a light background—a bizarrely shaped dust cloud opaque to the visible radiation of stars and nebulae. If there were no relatively bright emission nebula behind it, we might not even know about any dark gas-dust cosmic horse.

The background for the recognizable horse profile is created by the hydrogen nebula IC 434, discovered by William Herschel in the late 18th century. However, Herschel did not notice any amusing details in the outline of this nebula, although he was an excellent observer—much more keen-sighted and attentive than most of his followers. There are also objective reasons for this—telescopes in Herschel's era were imperfect, and their dark metal mirrors lost from 50% to 80% of the light that entered them.

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Rosette Nebula

Level of difficultyEasy
Reading time3 min
Views240

The large but sparsely populated constellation Monoceros, barely visible to the naked eye, can take pride in hosting an extraordinary treasure: the Rosette Nebula. Monoceros is a relatively recent addition to the star map. Lacking bright stars, astronomers of the pre-telescope era deemed this region unworthy of a constellation. After all, how could a constellation exist without luminous stars? A few 4th-magnitude stars hardly suffice to form a recognizable figure. Consequently, old star maps depicted nothing within the Winter Triangle — formed by Betelgeuse, Sirius, and Procyon (between the constellations Orion, Canis Major, and Canis Minor. Only with the telescope’s invention did it become clear that this region contained notable objects, necessitating a name. Johannes Hevelius, creator of a stunning star atlas, coined the name in the early 18th century. Thus, astronomers gradually accepted a mythical, horse-like beast with a sharp horn — located where the third eye might be — among the winter constellations.

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Carina Nebula

Level of difficultyEasy
Reading time3 min
Views354

The term "Carina Nebula" is sometimes translated as "Nebula of Carina," evoking the image of a beautiful female name. However, this is a misinterpretation. "Carina" is Latin for "keel," referring to the keel of a ship—not just any ship, but the Argo, depicted on ancient star maps. Over time, the Argo constellation was divided into several modern constellations: Carina, Puppis, Vela, and Pyxis (Compass). The stars of the Argo are invisible from mid-northern latitudes. Even in the best seasons (winter and spring), Carina, Puppis, and Vela remain below the horizon. They can be observed from the northern tropics and farther south. However, in ancient times, when Greek astronomers imagined the Argo in the sky, the Earth's rotational axis was positioned differently due to precession. This allowed the Argo to be visible from Mediterranean shores. Precession, a gradual shift in the Earth's axis, completes a full cycle every 26,000 years. Over three millennia, the stars of the Argo gradually disappeared from the northern sky.

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Top 11 Free AI Image Generators: Best AI Image Tools of 2025

Level of difficultyEasy
Reading time8 min
Views1.8K

Admit it, how many times have you wanted to quickly create an image for a post or presentation, but instead got stuck in an editor or endless searches for a suitable image on Google? Wouldn't it be great if the picture in your head could just appear instantly? Time is money, inspiration is on pause, and that's where AI comes to the rescue. Neural networks can generate anything you want, including the craziest ideas. No need to spend hours searching when, with a few clicks, you can see what was in your thoughts just a second ago.

By the way, notice the cover with the dinosaur? Let's call him Rex. Rex is himself a product of neural network creation. Today he'll be the main star of our experiments. But what will we do? Remember I mentioned crazy ideas? Well, to understand all the possibilities of generation, let's give AI a difficult task. We'll send Rex somewhere in space, for example to the Moon, let him put on a spacesuit and and have him grill some barbecue with Earth in the background. Interested? Then buckle up, we're heading into the world of image generation.

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Firebase Studio Explained: Features and How to Get Started

Level of difficultyEasy
Reading time4 min
Views1.3K

I recently tried using Firebase Studio, and it has been an interesting experience that I want to share with you. It's a free, browser-based tool from Google that allows you to build full-stack web apps with AI assistance. Want to know more? Then read this article until the end.

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Custom structure serialization in Unreal Engine

Level of difficultyMedium
Reading time3 min
Views827

Let’s say you’ve created your own USTRUCT in C++ and now you want to serialize it.

Usually, it’s enough to simply mark the desired fields with SaveGame. But here’s the problem — in order for this to work, the fields themselves must support serialization.
Unfortunately, one of our variables doesn’t.

In my case, it’s a struct called FNonSerializableStruct. Because of that, only the second struct gets serialized, even though we marked both with SaveGame.

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The Armenia Opportunity: EDA, ASIC, FPGA + connections with USA, China and Russia

Reading time9 min
Views1.2K

Armenia is a lucky country. Back in the 1990s somebody lobbied Synopsys, the #1 leader in the Electronic Design Automation market, to create a division there. It was joined by Mentor Graphics / Siemens EDA, another EDA leader, then NVidia. Synopsys Armenia became the largest Synopsys division outside the US Silicon Valley and Boston, although the Taiwanese may tell you otherwise. Since Synopsys and Mentor make software used by chip designers in Apple, Samsung, AMD and all other electronic companies, Armenia has an unfair advantage over all their neighbors in Caucasus and Central Asia.

In addition, Armenia has friendly relations with Russia, and most Armenians speak Russian as well. This has facilitated the move of many Russian companies to Armenia, for example, a RISC-V semiconductor IP provider Syntacore. Finally, as we can see from the recent conference EDA Connect, Armenia is attracting the attention of electronic and EDA companies from China.

EDA Connect featured not only academic and industrial papers but also a hackathon on FPGA design, attended by local students from Yerevan State University, the American University of Armenia, the Russian-Armenian University, the French University in Armenia and others.

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UENUM iteration in Unreal Engine

Level of difficultyEasy
Reading time3 min
Views759

I needed to create a category panel for placeable items in the UI — like the ones you see in city-building games. As a legacy, I inherited a ready-made UENUM, which may be modified in the future.

Naturally, I didn’t want to manually create and tweak every single widget — especially knowing that the list of categories might change later. I wanted something simple and reusable: just run a For each loop, generate everything on the fly, and ideally make it work for any enum, not just this one.

And there was a way! When you define a UENUM, Unreal automatically generates all the metadata and creates a corresponding UEnum object, which is a UObject. All you have to do is use that data properly.

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Building Debian Packages for PHP Extensions

Level of difficultyMedium
Reading time19 min
Views873

Historically, we’ve ended up using a few rather obscure PHP extensions—written and barely (if at all) maintained by their original authors—that aren’t available in standard Debian package sources.

We stick to the principle of “do it right, and it’ll work right,” which means Slackware-style dropping binaries into the system outside of package managers is frowned upon.

So instead, we’ll be building proper .deb packages for PHP extensions—without breaking compatibility with the existing environment.

Let’s go do us some compilin’, shall we?

A Tale of How Not to Turn Your Cisco Router into a Public DNS and NTP Server by Accident

Level of difficultyEasy
Reading time6 min
Views743

The Cisco IOS/IOS-XE operating system is a source of inspiration for many other vendors. The internet is full of guides on how to configure a typical Cisco router for SOHO scenarios. However, unlike consumer-grade routers, configuring something like Cisco IOS requires caution. If you don’t think things through, the router may start "living its own life" and end up, for instance, as a DDoS amplification tool.

Let’s dive in

A Quick Guide to Setting Up SNMPv3

Reading time7 min
Views726

Setting up a v3 user on the server-side agent for the default Linux snmpd (net-snmp package). Out of scope: SNMP traps and read-write (rw) users.

SNMP version 3 allows packet transmission in encrypted form, making it safe to transfer telemetry over public networks without the risk of exposing either authentication information (analogous to a community string) or the data stream itself, which is encrypted using a symmetric algorithm with a shared key.

Let me figure it out →

ReCAPTCHA Enterprise Bypass: Full Review, Recognition (Bypassing) and what Captcha Solvers can Bypass it

Level of difficultyEasy
Reading time29 min
Views1.3K

Modern services (websites) ubiquitously deploy CAPTCHAs for protection, complicating life for developers, SEO specialists, and automation engineers (although the original aim was not to frustrate automators but rather to minimize excessive load on resources from such actors). Among the multitude of CAPTCHAs, Google reCAPTCHA Enterprise stands out as one of the most advanced bot protection systems in this line-up. It is capable of analyzing user behavior and blocking suspicious activity, thereby significantly hindering the recognition of reCAPTCHA Enterprise and its automated bypass. Let’s break down what reCAPTCHA Enterprise is, how it differs from versions v2/v3, and why it is so difficult to bypass (or is it?).

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Gemini 2.5 Pro: My Ultimate Developer Guide & FAQ (Code, Cost, Limits & More!)

Level of difficultyEasy
Reading time5 min
Views2.8K

Since sharing my initial thoughts on Google's Gemini 2.5 Pro, I've dug even deeper and gathered answers to many common questions developers like us might have. This AI model is making waves, so let's break down everything you need to know – from its groundbreaking features to the practical stuff like cost and limitations.

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How to add any CSS framework to your project. Part 2

Level of difficultyEasy
Reading time4 min
Views881

Typically, I use the following structure for global styles in any project. This setup allows for a highly flexible, easy-to-read, and maintainable style system, which is crucial for large projects that may last several months or even years.

Let’s review each of these folders:

Common: contains typography styles, imported fonts, icons, and core styles used across the project, such as container.scss or helpers.scss.

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The Links Theory 0.0.2

Level of difficultyMedium
Reading time26 min
Views1.3K

This world needs a new theory — a theory that could describe all the theories on the planet. A theory that could easily describe philosophy, mathematics, physics, and psychology. The one that makes all kinds of sciences computable.

This is exactly what we are working on. If we succeed, this theory will become the unified meta-theory of everything.

A year has passed since our last publication, and our task is to share the progress with our English-speaking audience. This is still not a stable version; it’s a draft. Therefore, we welcome any feedback, as well as your participation in the development of the links theory.

As with everything we have done before, the links theory is published and released into the public domain — it belongs to humanity, that means, it is yours. This work has many authors, but the work itself is far more important than any specific authorship. We hope that today it can become useful to more people.

We invite you to become a part of this exciting adventure.

Witness the birth of meta-theory

Gemma 3 Tutorial for Beginners – Google’s Most Powerful Open AI

Level of difficultyEasy
Reading time6 min
Views2K

Google has introduced Gemma 3, a collection of lightweight, open-source AI models designed for efficient performance across various devices, from smartphones to workstations. Building upon the technology of the Gemini 2.0 models, Gemma 3 supports over 140 languages and offers advanced text and visual reasoning capabilities. What's to know more? Then, read this article until the end.

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