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What's New in the Angie 1.9 Web Server (an nginx fork) and What to Expect from 1.10?

Level of difficultyEasy
Reading time8 min
Views1.2K

You may have already read in the news that on the eve of Cosmonautics Day, a new stable release of Angie 1.9.0 was released, an nginx fork that continues to be developed by the team of former nginx developers. Approximately every quarter, we try to release new stable versions and delight users with numerous improvements. This release is no exception, but it's one thing to read a dry changelog and quite another to get to know the functionality in more detail, to learn how and in which cases it can be applied.

The list of innovations that we will discuss in more detail:

— Saving shared memory zones with cache index to disk;
— Persistent switching to a backup group of proxied servers;
— 0-RTT in the stream module;
— New busy status for proxied servers in the built-in statistics API;
— Improvements to the ACME module, which allows automatic obtaining of Let's Encrypt TLS certificates and others;
— Caching TLS certificates when using variables.

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How to catch and optimize problematic queries in PostgreSQL

Level of difficultyMedium
Reading time8 min
Views1.1K

If you work with PostgreSQL, you've likely run into performance issues at some point — especially as your database grows. Things may have been running smoothly at first, but as your client database expanded, queries started slowing down. Sound familiar? Here's a guide to help you identify and fix problematic queries, so you can get your PostgreSQL database running at peak performance again.

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Tips and methods for conducting user research with children

Level of difficultyEasy
Reading time5 min
Views1.4K

When creating an app or any other software product for children, one of the hardest parts of the process is conducting user research correctly. Although working with kids might seem fun and entertaining, it takes certain skills to get them engaged in testing your product and voicing their opinion so you could gather all the necessary information. It’s important to understand that mentally kids function differently than adults, so working with a young target audience requires a different approach. Treating children like adults in the UX research process can lead to serious mistakes: they might not get a proper understanding of your product and you might end up getting wrong results, only wasting your time and budget. In order to avoid that, we’ve collected a few tips below that might help you communicate with kids more effectively for a productive and fruitful research session.

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One-click Postgres Pro optimization with pgpro_tune

Level of difficultyEasy
Reading time4 min
Views741

Imagine a familiar situation: it’s Monday morning, tasks are piling up, and you need to quickly spin up a new service using Postgres Pro. Or maybe you’ve just upgraded your database server over the weekend — added more CPUs, more RAM.

Here’s how to get your database tuned and ready to make the most of the new hardware and workload, without wasting time.

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Database performance analysis using pg_profile and pgpro_pwr

Level of difficultyEasy
Reading time4 min
Views616

DBAs often struggle to identify the most resource-hungry processes that degrade system performance. Back in 2017, DBA — and now Postgres Professional engineer — Andrey Zubkov faced the same challenge. This led him to develop pg_profile for PostgreSQL, which has since evolved into pgpro_pwr.

In this article, we’ll dive into strategic database monitoring and show you how to pinpoint bottlenecks in your databases using our tools.

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How to Fail Those Students Who Rely on ChatGPT

Reading time3 min
Views2.6K

We at Verilog Meetup constructed an exam/interview problem that has an interesting property: if a student tries to figure out a solution by thinking by himself, he usually succeeds; however if he dumps the problem on ChatGPT, the solution fails (does not pass the automated test), and the student goes into a death spiral of futility, kicking ChatGPT to get the solution right.

There is nothing weird about the problem, we do this in the industry all the time:

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Google ADK: Easiest Way to Build an AI Agent

Level of difficultyEasy
Reading time7 min
Views4.9K

In this tutorial, I’ll explain in simple terms what AI, AI agents, and workflows are, and then I’ll walk you through building your very first AI agent in Python using Google’s Agent Development Kit (ADK). By the end, you’ll understand the differences between these concepts and have a working content-assistant agent you can run from your terminal or a web interface.

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By next year, we'll be talking to databases in natural language

Level of difficultyEasy
Reading time4 min
Views763

According to Gartner, natural language queries will replace SQL as early as 2026. 

While Gartner's prediction may be optimistic, the shift toward natural language interfaces for databases is inevitable. The timeline may vary, but the transition itself is a certainty.

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What is DPI Engine?

Level of difficultyMedium
Reading time25 min
Views1.9K

For people familiar with the term DPI (Deep Packet Inspection), it often carries an unpleasant association: blocking, regulators, censorship, tightening controls. In reality, DPI is simply the name of a technology whose essence lies in the deep analysis of network traffic. Deep traffic analysis involves identifying protocols, extracting the most significant fields and metadata, classifying internet services, and analyzing the nature of network flows. I will explain how such solutions work in this article.

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Yandex huge privacy issue or not?

Reading time2 min
Views2.1K

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
Views1.3K

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
Views1.2K

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
Views1.3K

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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