zelo

Location: Poland (CET / UTC+1)

Remote: Yes (open to occasional travel)

Willing to relocate: No

Technologies: Python (asyncio, Django, FastAPI, Playwright), reverse engineering (TCP/UDP, Modbus, CAN, private APIs, firmware), Linux networking (multi-WAN, iptables, custom routing), Docker, Proxmox, PostgreSQL, motion control/CNC, embedded (RPi CM4, AVR, PCB/CAD)

Résumé/CV: on request

Email: [email protected]

13+ years in software, test infrastructure and R&D. Hands-on from soldering and firmware up to backend, servers and cloud. Most of my work starts where the vendor says "not supported" or there's simply no API.

Some examples:

- Adaptive laser processing machine. A multi-axis CNC that 3D-scans every piece of natural material and adjusts the laser path to its actual shape. I designed and built it alone, end to end. The material is fragile, flexible and irregular, which needed a custom vacuum workholding system to keep each piece in a repeatable position. Keyence ships its laser scanner with Windows DLLs only; I reverse-engineered the TCP/UDP protocol and wrote a Linux acquisition stack in Python.

- LTE proxy farm for large-scale data acquisition. Modified Huawei modem firmware to expose undocumented APIs, wrote Python radio drivers, and got IP rotation under 0.5 s without radio reboots. Multi-WAN routing on Raspberry Pis, one LTE interface per proxy.

- Revolut, built the underwriting engine from scratch in 6 months, required for the Lithuanian banking license and the Polish credit launch.

- ABB, hardware lab in CI. Worked with mechanical designers on custom test benches and owned their control end to end. Wrote DX-first Python libraries with a fully object-oriented abstraction over the hardware (Modbus/BLE drives and sensors), so testers wrote tests without knowing the protocols. Then integrated the whole lab with Azure DevOps to run those tests on real hardware from CI. CI agents ran on repurposed x86 terminals, much cheaper than the ARM (rpi) alternative and using better supported cpu architecture.

- IoT cargo monitoring startup, co-founder/CTO. Co-designed a custom RPi CM4 carrier board and AVR power management, and decoded undocumented vehicle CAN signals. Helped secure EU grant.

Best fit: small teams with problems that don't have a known answer yet. R&D prototypes, reverse engineering, data acquisition, hardware/software integration. B2B, consulting or full-time.

Zephyr rtos on raspberry pi sbc https://github.com/jetpax/PiZZa/tree/main

In Poland everything found in the ground belongs to the nation treasury (government) and performing excavation in order to look for things like this is illegal without specific permit. So if you find something you either stash it and don't talk about it or it goes to museums.

That's awesome! It made me a bit nostalgic, thinking back to the first program I ever wrote. It was a WoW bot that walked between the mailbox and the auction house, manipulating auction prices. The bot would drive the glyph prices to the bottom by lowering the lowest price by just 1 bronze to always be the cheapest when sorted by price. Then, it would buy up the entire market stock and offer everything for 50 gold each, starting the cycle again. It was glue code between Lua extensions and xdotool, all written in Bash, running WoW under Wine on Linux. The bot was pulling in about 20K gold per day on a single account.

The fun part is, I was 14 years old and had zero programming knowledge at the time—just a feeling that this process could be automated and access to Google. The bot was reading the game state by capturing specific parts of the screen and comparing MD5 checksums of where the buttons were supposed to appear. I used xdotool for mouse and keyboard input, along with in-game settings like Lua command execution inside the game console to target specific NPCs or mailboxes and click to move. It probably pushed me toward pursuing a career in this industry.

Like this https://en.m.wikipedia.org/wiki/Molten-salt_battery

Btw touristic heaters are based on https://en.m.wikipedia.org/wiki/Sodium_acetate and that's also energy storage

micropython supports esp32 too

I checked droidcam before and AFAIK it solves the problem of using adnroid device as webcam using server and client apps.

I want to expose low level camera capabilities like manual focus controll, capturing raw images, iso, etc. DroidCam exposes only subset of functionality I need.

In short i want it to be more like programmable controlled digital camera than webcam.

BTW scrcpy offers similar features trough adb to DroidCam.

I'm working on android app that exposes camera stack trough http/websocket API.

The idea is that phones have very nice cameras and lot of media processing power and such API could enable hackers to easily incorporate capable camera stack in to their projects without android development experience in any language they like.

There are millions of working phones in the drawers battery backed, with plenty of computing power, nice cameras, hardware acceleration, good connectivity (WiFi, ethernet over usb), that could get new purpose.

Previously I was working on automated photogrammetry rig and this is perfect use case for that.

If you see other use case for such API share your ideas.

If you think that's cool idea to develop and would like to help write me at [email protected]

Location: Poland / Europe

Remote: Preferred

Willing to relocate: Maybe

Technologies: Python, Django, Flask, FastAPI, Selenium WebDriver, Playwright, Appium, jMeter, locust.io, Docker, CI/CD, Git, HTML, CSS, JavaScript, Linux, Quality Assurance, Mobile and Browser Automation, Performance Testing, Industrial Automation, IoT Testing, Hardware testing

Résumé/CV: Available on request

Email: [email protected]

Linkedin: https://www.linkedin.com/in/wojciechzelek/

I am looking for opportunities where I can bring my Python development and QA automation skills to life. My experience includes leading the implementation of an underwriting engine in fintech, creating several products for classical musicians, developing an MVP for a cargo tracking product, hacking LTE modems for high-quality residential proxies, writing drivers/automation for testing sensors on robust electrical motors or using python for programmatic model generation in CAD. I am passionate about backend development, testing automation and hacking stuff for fun and profit. I thrive on diving into innovative projects and driving impactful solutions, especially when some physical aspect (e.g. hardware) is involved. While I prefer remote roles, I am open to relocating for the right opportunity.

Although it happened in 2020 It's still their current flagship 140 usd keyboard, not legacy product.

But I understand that it could make support logistic harder to offer parts that shouldn't need to be replaced.

I put my Logitech MX keyboard in the bag with few other things and one of the keycap broke off. Completely my fault. Since the key mechanism was intact I have told their support what happened and asked if they sell replacement keycaps and got completely new keyboard for free.

Great support but I was left with mixed feelings since I still had almost completely working keyboard and I think the experience would be better if they would send me just the keycap.

Location: Poland / Europe

Remote: Preferred

Willing to relocate: Maybe

Technologies: Python, Django, Flask, FastAPI, Selenium WebDriver, Playwright, Appium, jMeter, locust.io, Docker, Jenkins, Git, HTML, CSS, JavaScript, Linux, DevOps, Quality Assurance, Mobile and Browser Automation, Performance Testing, Industrial Automation, IoT Testing, Hardware testing

Résumé/CV: Available on request

Email: [email protected]

Linkedin: https://www.linkedin.com/in/wojciechzelek/

Looking for opportunities where I can bring my Python development and QA automation skills to life. I've worked across a broad range of industries—fintech, music, cargo tracking, and industrial automation. I'm all about backend development, testing automation, and diving into innovative projects. Prefer remote roles, but I'm open to relocating for the right opportunity.

Location: Poland / Europe

Remote: Preferred

Willing to relocate: Maybe

Technologies: Python, Django, Flask, FastAPI, Selenium WebDriver, Playwright, Appium, jMeter, locust.io, Docker, Jenkins, Git, HTML, CSS, JavaScript, Linux, DevOps, Quality Assurance, Mobile and Browser Automation, Performance Testing, Industrial Automation, IoT Testing, Hardware testing

Résumé/CV: Available on request

Email: [email protected]

Linkedin: https://www.linkedin.com/in/wojciechzelek/

Looking for opportunities where I can bring my Python development and QA automation skills to life. I've worked across a broad range of industries—fintech, music, cargo tracking, and industrial automation—to deliver scalable, efficient solutions. I'm all about backend development, testing automation, and diving into innovative projects. Prefer remote roles, but I'm open to relocating for the right opportunity.

Maybe that will interest you https://80.lv/articles/kiri-engine-creates-meshes-from-3d-ga...

Location: Europe

Remote: Yes

Willing to relocate: No

Technologies:

    - Quality Assurance: Browser Automation (Selenium WebDriver, Playwright), Mobile Automation (Appium), Performance Testing (jMeter, locust.io), CI/CD(Jenkins, drone.io, CircleCI, GitLab CI), Faking External Services, HTTP, XPath

    - Python Development: Web Frameworks (django, django rest framework, flask, falcon), Web Scraping (Scrapy, Mechanize, Requests), Pandas, Celery, AsyncIO

    - Other: HTML, CSS, Web Bots Detection Avoidance

    - Dev Ops: Linux Administration, Docker (docker compose), Virtualization (qemu), bash

Résumé/CV: https://drive.google.com/file/d/1tTnYRdOFWgLh-pB1FGbOaLGtgdH...

Email: See contact info in resume

I'm quality assurance / backend engineer with broad knowledge about entire application stack and experience in more complex automated test setups. Looking for interesting project to work on.

Location: Europe

Remote: Yes

Willing to relocate: No

Technologies:

    - Quality Assurance: Browser Automation (Selenium WebDriver, Capybara, Protractor), Mobile Automation (Appium), Performance Testing (jMeter, locust.io), CI/CD(Jenkins, drone.io, CircleCI, GitLab CI), Faking External Services, HTTP, XPath

    - Python Development: Web Frameworks (django, django rest framework, flask, falcon), Web Scraping (Scrapy, Mechanize, Requests), Pandas, Celery, AsyncIO

    - Other: HTML, CSS, Web Bots Detection Avoidance

    - Dev Ops: Linux Administration, Docker (docker compose), Virtualization (qemu), bash

Résumé/CV: https://drive.google.com/file/d/1tTnYRdOFWgLh-pB1FGbOaLGtgdH...

Email: See contact info in resume

I'm quality assurance / backend engineer with broad knowledge about entire application stack and experience in more complex automated test setups.

Location: Poland/Europe

Remote: Yes

Willing to relocate: No

Technologies: Python, Linux, Docker, Selenium, Django, Flask

Résumé/CV: https://drive.google.com/file/d/1tTnYRdOFWgLh-pB1FGbOaLGtgdH...

Email: See contact info in resume

I'm experienced qa/backend engineer with broad knowledge about entire application stack, currently looking for opportunity to connect those two areas and solve more challenging quality assurance problems.

I use nomachine behind vpn and it works much smoother than teamviewer. It's multiplatform and free for personal use.

I had a problem with not charging booting mi notebook pro and managed to fix it by unplugging battery for few minutes. It happened to me twice in 1.5 years of usage.

I still recommend this device. Currently I'm forced to use macbook pro 15 with touchbar and it's ergonomy is really awful.

Location: Cracow, Poland

Remote: Yes (I don't mind on-site meet-ups from time to time)

Willing to relocate: No

Technologies: Web Frameworks (Django, django rest framework, Flask, Falcon), Web Scraping (Scrapy, Mechanize, Requests), Pandas, Celery, AsyncIO, Redis, PostgreSQL, Linux, Docker, Docker Compose, Qemu, Browser Automation (Selenium WebDriver, Capybara, Protractor, Puppeteer), Mobile Automation (Appium), Performance Testing (jMeter, locust.io), CI/CD(Jenkins, drone.io), Faking External Services

Résumé/CV: https://drive.google.com/file/d/10bKQF_DxoauGhZvRn5UVWS4cNd0...

Email: It's on CV

I'm looking for a position as a Python Developer or Quality Assurance Engineer.

Selenium for sure doesn't fit in your use case then :). I pointed "user-centric approach" because selenium focuses on allowing only things normal user could do in normal user way which is limiting for automation but it's a blessing if you want to look as close to the real user as you can. I worked on solving google ReCaptcha v2/v3 at bigger scale and it's been a solid advantage.

> And javascript code in a string of python can not be linted, which increases debugging workload.

If you use PyCharm or any other JetBrains IDE you can use `Language Injections` [0]

> I am wondering if using puppeteer can ease pains mentioned above.

I'm not sure about puppeteer but Chrome DevTools Protocol [1] (I think this is what puppeteer use under the hood, but I'm not sure) may be interesting for you because it gives low level access to browser mechanisms like injecting code before page load, request interception or separate browser contexts between separate tabs.

[0] https://www.jetbrains.com/help/pycharm/using-language-inject...

[1] https://chromedevtools.github.io/devtools-protocol/

It's probably because in the meantime dom nodes has been replaced by new ones.

Selenium has it's quirks but when you understand how it works and it's limitations and user centric philosophy there is nothing that can stop you from writing rock solid stable tests.

I'm working on Xiaomi Notebook Pro 15" i7-8550U/16GB/256SSD (+ one empty slot for ssd)/Nvidia MX150. I'm using it with Ubuntu for python development and it costed me around 1200$. Battery life is around 8h of work in PyCharm (Jetbrains IDE based on the same technology as android studio). I know that some people overclock gpu under windows because of cooling capacity. I'm overally very satisfied and recommend it if you are willing to have notebook without warranty.

I'm pretty sure that Jimmy Joy (Joylent) is still better-balanced food than what you prepare in a house or buy in a restaurant.

Location: Poland (EU), Cracow

Remote: Yes

Willing to relocate: Yes

Technologies: linux, python, django, scrapy, bash, selenium, appium, html, css

Résumé/CV: https://drive.google.com/file/d/0B5vXwnjEbr0IR1NKb0R6ejdxcDV...

Email: [email protected]

Seeking job as QA or DevOps/WebDev engineer.