@Lucian

Learning^Paths

Hi! 👋🏻 Here you'll discover learning paths to reach your full potential.

Never fail a technical interview again.

And, Take your system design skills to the next level!

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20K+Students taught
60K+YouTube subscribers
14+ yearsProfessional experience
7Courses created

Choose your next learning path

Learn deeply, practice deliberately, or start free.

Each path solves a different preparation problem. Pick the one that matches what you need next.

How the material is built

Less memorization. More engineering judgment.

The same three principles shape the courses, interview questions, and free learning resources.

🔎

Understand the why

Start from the problem and constraints before introducing a technology or pattern.

Problem → constraints → options
⚖️

Practice the decision

Compare alternatives and make the trade-off visible instead of hiding it behind jargon.

Options → trade-off → choice
💬

Explain with confidence

Turn technical understanding into a clear answer you can defend under pressure.

Decision → reason → defense

What students say

The result matters more than the rating.

Real comments from students and YouTube viewers—not anonymous marketing quotes.

I'm a PM for a fintech firm. This video is brilliant!! There were so many edge cases that you laid out very well and also explained industry standard solutions. Also, you've structured the video really well. Top class!!! Would've loved if you included DB design as well, but that'd probably be me asking for too much. Thanks again.
KK aka Neil ThomasYouTube viewer · Payment System Design
You're amazing bro, thank you so much for making these videos! I'm preparing for a senior engineering interview and haven't been feeling very confident about it. Your videos are really helping me build a framework for understanding things at a more high level. I appreciate your effort. Thanks again!
OzzyfromspaceYouTube viewer
The way you explained the theory made it very clear, and the hands-on exercises, though short, were practical and effective.
KerianUdemy student · PostgreSQL High Availability
Thank you so much for the effort you put into this video! Your explanation is incredible and the graphic is easy to understand 😊. I instantly subscribed.
Tuyet Lan VuYouTube viewer · Payment System Design
Best video!! Explained everything I learned in 4 months in 24 mins
Emily EdgarsYouTube viewer
This video is very informative, straight to the point and so well done.
@collinskariuki7089YouTube viewer · REST API Design
At first I was skeptical, but the more I watched, I learned very important patterns for designing a distributed payment system. well done!
SoftwareEngineeringYouTube viewer · Payment System Design
The way the units are split favors advancing quickly. I am using it to prepare for a work interview.
Fernando SolarUdemy student · PostgreSQL High Availability
Thank you for this video. Any System Designer or a Technical Architect can easily understand the effort and hard work to come up with such presentable content and sharing knowledge.
Raghunandan C NYouTube viewer · Payment System Design
This was such a good tutorial for someone like me who is new to these concepts…
@rupeshchandramohanty416YouTube viewer · Payment System Design
Short and to the point! In just 3 hours a very good, practice-oriented introduction to the most important tools with demonstrations in each section.
GernotUdemy student · PostgreSQL High Availability
This is pure ambrosia. Ah, feed me more, feed me more. I'm savoring each video in the playlist, one at a time, to make it last as long as possible.
HankYouTube viewer · Payment System Design

Not convinced yet? Here are even more testimonials.

Lucian Oprea presenting a backend engineering talk at DevTalks Bucharest

Your instructor

Hi, I’m Lucian.

I’m a backend engineer and educator with 14+ years of professional experience. I create the explanations and learning paths I wish I had when difficult concepts first appeared in interviews and production systems.

The goal is not to give you more material to collect. It is to help you make better technical decisions—and explain them clearly.

More about Lucian →

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