CatOps

21 Apr 2025 13:52

​​For today’s Donations Monday, I’d like to share with y’all a new fundraiser from Dzyga’s Paw - Save the Crabs 🦀

They are raising $110,000 to protect 15 Self-propelled artillery systems Krab with 15 Anti-Drone Systems.

#donations #Ukraine

CatOps

17 Apr 2025 18:07

As you may know, there was a KubeCon Europe recently in London.

I didn’t go there, but here a member of our community shares his thoughts about the conference on LinkedIn.

Also, if you understand Ukrainian and prefer the video format, you can also check out the video from Den Vasyliev as well.

#event #kubernetes

CatOps

15 Apr 2025 18:33

Debezium is a popular open source tool to implement the CDC (change data capture) pattern for various data sources.

This article provides some highlights of how it works for PostgreSQL as well as it covers some practical implications of working with Debezium like figuring out LSNs, failing over to a replica, and so on.


#databases

CatOps

11 Apr 2025 14:55

Recently, Git celebrated its 20th anniversary, and the pre-commit framework marked 11 years.

Interestingly, despite their longevity, these technologies are still not being used to their full potential — especially when it comes to leveraging git hooks.

To shed some light on this, I gave a talk about them (in Ukrainian): https://youtu.be/mqzyVg5WOMM
This is a natural continuation of my previous talk on the same topic, which I gave back in 2018 :)
Covered (and skipped) topics and link to the older talk in video description. Enjoy!


#git

CatOps

08 Apr 2025 11:36

According to DOU, Python is the most popular programming language among the DevOps-related specialists who understand Ukrainian.

Pydantic is a popular library for configuration validation, including the configuration that comes from the environment. However, it can break the unit tests, if the required environment variables are not present.

However, you can create a fixture for your Pydantic configuration that patches the environment, so your tests are isolated. Here's an article that describes, how to do that.

#python #programming

CatOps

05 Apr 2025 13:18

Saturday afternoon is the ideal time to listen to 3 hours of a discussion about AI in the new episode of our CatOps Voice Chat (in Ukrainian).

There are a lot of useful links in the description as well, so check it out!

You can find the new episode on:

- YouTube
- Substack
- Spotify
- Apple Podcasts
- RSS Feed

Hope you enjoy it!

#voice_chat #говорилка #ai

CatOps

03 Apr 2025 12:17

Helm docs is a neat tool for generating documentation based on your values.yaml file.

I recall, I wanted to write something similar back in a day, but I got bitten in the ass by YAML parsing 🙃

#kubernetes #helm

CatOps

01 Apr 2025 19:14

Lurking Variables is a story about contributing factors. Specifically, those factors that people do not take into account right away, or better said, are not instinctively taken into account.

Anyway, this is a good read about a very real problem of confirmation bias when handling incidents.

#sre #incidents

CatOps

30 Mar 2025 16:14

A new issue of the CatOps Digest is here:
https://newsletter.catops.dev/p/catops-digest-2025-03-30

#digest #newsletter

CatOps

25 Mar 2025 07:27

We are continuing our security marathon with some news about very popular NGINX Ingress for Kubernetes.

Wiz Research discovered CVE-2025-1097, CVE-2025-1098, CVE-2025-24514 and CVE-2025-1974, a series of unauthenticated Remote Code Execution vulnerabilities in Ingress NGINX Controller for Kubernetes.

Exploiting these vulnerabilities can lead to unauthorized access to cluster secrets as well as remote code execution inside the ingress pod.

This vulnerability is fixed in Ingress NGINX Controller version 1.12.1 and 1.11.5, but if you cannot upgrade right now for whatever reason, Wiz has other recommendations on how to mitigate this.

P.S. Many thanks to the chat for sharing this story!

#security #kubernetes #nginx

CatOps

23 Mar 2025 13:41

A new vulnerability is discovered in Next.js - a popular web framework based on React. This vulnerability allows an attacker to bypass the redirect middleware as well as potentially make a cache poisoning attack.

Here’s also a thread by Gergely Orosz about this issue.

#security

CatOps

21 Mar 2025 10:39

A sneak peek into the database design based on two incredible books: "Database Internals" by Alex Petrov and "Designing Data-Intensive Applications" by Martin Kleppmann. Mostly on the first one, though.

This article touches topics of ACID, underlaying data structures (B- & LSM-trees), and distributed systems. Just like the aforementioned books, which I also highly recommend!

A random quote:

> Going distributed should be a last mile resort, introducing it to a system adds a ton of complexity, as we will soon learn. Please avoid using distributed systems when non distributed solutions suffice.

#databases

CatOps

18 Mar 2025 14:59

Python is incredibly popular programming language among DevOps / Site Reliability / Platform specialists. It’s also used as the language of choice to build backend in many companies.

So, here is a book bundle by Packt to enhance your Python skills:

https://www.humblebundle.com/books/python-from-beginner-to-advanced-packt-books

P.S. I know that many folks are skeptical about Packt books, so keep this in mind. I still think it worth sharing, though.

CatOps

15 Mar 2025 15:39

There are two types of folks: those who pin their dependencies to (often) mutable tags and other pointers, and those who already pin to hash sums.

This is true for GitHub Actions as well. For example, most tags in the tj-actions/changed-files repository were repointed to compromised versions by an attacker, potentially affecting 23,000 repositories until GitHub shut down the entire repository.

Manually pinning dependencies can be tedious, so it's better to utilize tools like Renovate. The SpotOnInc/renovate-config preset does exactly that. Note that you can pin it to a hash sum too, just in case ;)

P.S. If you used that GitHub Action, here is a list of possible mitigation steps: antonbabenko/pre-commit-terraform#837.

#security #github #gha

CatOps

12 Mar 2025 11:51

Git is one of those things, where you can discover new things even after decades of using it.

This article provides some tricks you could do with Git. If you knew those already - that's cool. If not, you're welcome :)

#git

CatOps

18 Apr 2025 09:30

You may have noticed a train of released AI stuff here and there. In recent times, everyone started rushing towards AI agents to vendor-lock you to their solutions even more.

And do you know why they are able to do it so relatively easily?

https://ampcode.com/how-to-build-an-agent

P.S. 400 lines of Go code. If you remove all if err != nil by using something like Python, it will be half or even fewer lines. Yep

#ai

CatOps

16 Apr 2025 14:20

A very nice video by Confluent that introduces Apache Iceberg:

https://youtu.be/TsmhRZElPvM?si=JA5hcWCT1iOEKEkt

#data

CatOps

14 Apr 2025 19:05

​​For today's Donations Monday, I'd like to remind you about the UA Responders charity foundations who specialize in tactical medicine.

I know these folks personally, so I feel absolutely confident recommending them to you!

CatOps

09 Apr 2025 17:58

Firefly has release a State of IaC 2025 report. As usual, you can obtain it in exchange for your personal data 🙃

#iac #terraform

CatOps

07 Apr 2025 20:19

​​​​For today's Donations Monday I’d like to remind you about a fundraiser from Dzyga's Paw that they do together with 7 different units.

https://send.monobank.ua/jar/7CRy1e16Qk

Here's the description from Dzyga's Paw themselves.

Dzyga’s Paw Fund, in partnership with seven units, is launching a $300,000 fundraiser to provide them with 90 night drones — essential for precision and safety in night operations.
Donate now to support project Triad: https://dzygaspaw.com/triad-night-drones
We are bringing together two powerful forces: our international supporters and Ukrainians backing their brigades. No matter what they say, Ukraine is not tired. Our defenders fight on, and we stand with them. And our friends from all over the world are eager to help us with this mission.
Join our ambassador team to help reach this ambitious goal faster — start a smaller fundraiser! Write to us in DM, and we will provide you with all the information, visuals, and donation chart.
This war has lasted nearly 11 years, and the last three have been the most brutal. Against all odds, Ukraine continues to resist. It is our duty to ensure our defenders have the tools they need to win!

#donations #Ukraine

CatOps

04 Apr 2025 13:56

Depending on your seniority and title, working with diagrams may take a big chunk of your day-to-day work.

Here's a collection of diagram creation tools, so you could pick something that suits your needs. Some of these
projects are quite famous - others not so much. I personally found some
interesting things there. It's not guaranteed that I will use them, but
still.

Also, speaking of diagrams, I can recommend this talk
from FOSDEM 2023. It's not a super-entertaining one, but it has some
good suggestions on how to draw your diagrams. The talk itself if
wrapped into Kubernetes, but those suggestions are universal.

#diagrams

CatOps

02 Apr 2025 09:15

“5 Whys” is a fairly popular framework for searching for a contributing factors of an incident.

However, this framework has its own limitations. Here is an article that presents these limitations in a concise way.

#sre

CatOps

31 Mar 2025 15:15

​​For today's Donations Monday we have a fundraiser from Dzyga's Paw that they do together with 7 different units. My friend's brother serves in one of those units.

https://send.monobank.ua/jar/7CRy1e16Qk

Here's the description from Dzyga's Paw themselves.

Dzyga’s Paw Fund, in partnership with seven units, is launching a $300,000 fundraiser to provide them with 90 night drones — essential for precision and safety in night operations.
Donate now to support project Triad: https://dzygaspaw.com/triad-night-drones
We are bringing together two powerful forces: our international supporters and Ukrainians backing their brigades. No matter what they say, Ukraine is not tired. Our defenders fight on, and we stand with them. And our friends from all over the world are eager to help us with this mission.
Join our ambassador team to help reach this ambitious goal faster — start a smaller fundraiser! Write to us in DM, and we will provide you with all the information, visuals, and donation chart.
This war has lasted nearly 11 years, and the last three have been the most brutal. Against all odds, Ukraine continues to resist. It is our duty to ensure our defenders have the tools they need to win!

#donations #Ukraine

CatOps

26 Mar 2025 13:05

Some books on programming and software architecture on Humble Bundle.

#books #programming

CatOps

24 Mar 2025 11:48

​​Last week, we closed Maksym's jar for Hospitallers in a day! Let's now do the same favor to another ember of our community - Dmytro!

His wife is raising funds to repair two cars for the 41st separate mechanized brigade. The goal of the support jar is 30k UAH. Also, there's a raffle for all the donations which are multiples of 100 UAH.

More info about the raffle is in this Instagram post (in Ukrainian):
https://www.instagram.com/p/DHV5cfCg1GU/

#donations #Ukraine

CatOps

22 Mar 2025 09:30

AWS gives a chance to complete some certifications for free, but with few preconditions

Covered certs:
- Foundational: Cloud Practitioner, AI Practitioner
- Associate: Solutions Architect, SysOps Administrator, Developer, Data Engineer, Machine Learning Engineer

Note, that you need to prepare and pass exam(s) before Aug 2025.

#aws #certification

CatOps

19 Mar 2025 11:55

Today, I'd like to share with you a nice YouTube channel Polylog, that does short explainer videos about the computer science concepts.

PolylogCS" rel="nofollow">https://www.youtube.com/@PolylogCS

#programming #cs #youtube

CatOps

17 Mar 2025 11:02

​The highest priority after completing the task is to preserve the life and health of the personnel. So, let's help raise money for tactical medicine!

TL;DR: Donate to Monobank jar till EOW and I will double the amount raised[1].

The Hospitallers Battalion is a volunteer formation known for its professionalism and dedication. When I say "voluntarily," I mean that you can join for a rotation, for example, for 2 weeks, and then return to civilian life for a few months before repeating the process. This flexibility allows specialists who, for various reasons, do not want or cannot join AFU still contribute to defensive operations. However, since the Hospitallers are a volunteer formation, their funding relies on donations from ordinary people.

Currently, the Hospitallers are raising 7.5 million UAH (~$180k) for this spring.
Let's aim to raise at least 10k UAH from CatOps by the end of the week, and I will double the amount raised[1].

Monobank jar: https://send.monobank.ua/jar/6eEHjgDTGq

Btw, the Hospitallers offer courses on first aid and tactical medicine that are available to civilians. I recently took the TCCC ASM (3-day) course, and it was excellent. You can check out their courses at Hospitallers Courses site and track new dates on their Telegram channel.

#donations #Ukraine

[1] But not more than 20k UAH/month from me until the fund campaign is closed or until I have doubled the amount, whichever comes first.

CatOps

14 Mar 2025 08:57

Yet another article from the old archives.

This one is about building a multicluster setup with Kubernetes using Kubernetes tools only. Moreover, there are more tools these days that can help you accomplish the architecture outlined in this article.

For example, you could use ClusterAPI instead of Crossplane for leaf-clusters and so on.

The only sad thing is that Kubernetes doesn’t support federation. So, any viable multi-cluster setup always boils down to two distinct approaches: a bunch of independent clusters, or a single leader with leaves.

#kubernetes

CatOps

11 Mar 2025 12:11

How to Scale Elasticsearch to Solve Your Scalability Issues is a neat guide for areas where you could optimize your ElasticSearch clusters.

Ties article doesn’t provide any concrete numbers, but gives plenty of suggestions. It makes sense, since any optimization heavily depends on one’s use case.

#elasticsearch