Level Up Coding @LevelUpCoding_

Stateful vs Stateless Design — What's the Difference? Stateless design is a powerful model that has led to the development of simple yet highly scalable and efficient applications. “State” refers to stored information that systems use to process requests. This information can…

How Does SSH Work? What actually happens when you type ssh user@host? The visual below lays out the sequential steps that occur between the SSH client and the SSH server. Here’s a breakdown of the main events that occur during an SSH connection: 𝟭) 𝗞𝗲𝘆 𝗲𝘅𝗰𝗵𝗮𝗻𝗴𝗲…

If you want to become good at code reviews, here are some techniques to consider: Most PR reviews fail when they focus on nitpicks, formatting, and style, while the real issues slip through. That’s the cost of reviews without context. They slow teams down instead of helping…

How API Gateways work (explained in 2 mins or less): An API gateway acts as a single entry point for clients. It simplifies client interactions with microservices. To understand how an API gateway works, let's look at how it processes a request: 𝟭) 𝗜𝗻𝗶𝘁𝗶𝗮𝗹…

Kafka vs AutoMQ — What's the difference? Kafka operates as a distributed pub-sub messaging system. Allowing applications to publish and subscribe to real-time data feeds. Its strengths? High throughput, scalability, fault-tolerance, and a mature ecosystem. But Kafka is also…

The Main Components of Docker Explained. Docker solves the "it worked on my machine" problem. It has a handful of core components. By understanding them you will have a strong fundamental understanding: 𝗜𝗺𝗮𝗴𝗲𝘀 ↳ Read-only templates that are used to build containers.…

🚨BREAKING: Kafka can now stream directly into Iceberg tables (zero ETL, zero copies). Until now, proprietary vendor solutions dominated this space, locking teams into closed ecosystems. But with Aiven’s open-source contribution, the playing field changes. Here’s why it…

The Main Components of Kubernetes Explained. At its core, Kubernetes is built on a handful of key components, each with a distinct role. By understanding them, you'll have a strong foundational understanding. 𝗡𝗼𝗱𝗲: ↳ Machines (physical or virtual) that run containerized…

How do we design effective and safe APIs? To understand some of the key principles and best practices of API design, Let's analyze a social media platform example: • 𝗥𝗲𝘀𝗼𝘂𝗿𝗰𝗲 𝗻𝗮𝗺𝗶𝗻𝗴 ↳ Clarity is key when creating APIs. Adopting simple resource names, like /users…

Well-structured prompt = working app. For complex systems, far from it. But for simpler apps, things have gotten this fast. Plan. Prompt. Build. Refine. This has become an increasingly viable option for building applications. When it comes to prototyping or building simpler…

Database indexing clearly explained. A database index is a lot like the index on the back of a book. It saves you time and energy by allowing you to easily find what you're looking for without having to flick through every page. Database indexes work the same way. An index…

Must-know principles of solution architecture design (explained in 2 mins or less): 7 core principles with actionable best practices for designing solutions: 𝗛𝗶𝗴𝗵𝗹𝘆 𝗮𝘃𝗮𝗶𝗹𝗮𝗯𝗹𝗲 𝗮𝗻𝗱 𝗿𝗲𝘀𝗶𝗹𝗶𝗲𝗻𝘁 ↳ High availability ensures systems stay operational despite…

6 types of API testing clearly explained. API testing significantly contributes to apps being reliable, secure, functional, and efficient by assessing the communication routes between software components. Six of the most important forms of API testing: • 𝗪𝗼𝗿𝗸𝗳𝗹𝗼𝘄…

If you’re serious about learning agentic AI, here’s a pathway I’ve found highly effective: I’ve been diving deeper into how to build multi-agent systems. A lot of courses out there are shallow in coverage. To build real AI agents, you need more than just tool usage or prompt…

How OAuth 2.0 works (explained in 2 mins or less): It can be thought of as a digital handshake between the app, service, and user, with everyone agreeing on what is shared. It's an authorization framework that enables applications to access a user’s data on another service…

Most AI coding tools look great in a demo. But on production codebases, they struggle. If you code with AI, read this: Why do a lot of AI coding tools struggle with larger codebases? Context. A CRUD app is one thing. Layered architecture, domain logic, tests, queries,…

Building auth is easy, all you need to do is: • Integrate with 10+ OAuth providers • Build signup, password reset, CAPTCHA flows • Implement rate-limiting, and 2FA • Detect fraud and secure sessions • Support SAML, SSO, account recovery • Handle edge cases when switching…

Git branching strategies clearly explained. When formulating your branching strategy, it's important to take into account the project’s complexity, the team’s size, and the release cycle. Let's look at some common approaches to branching: 𝗙𝗲𝗮𝘁𝘂𝗿𝗲 𝗯𝗿𝗮𝗻𝗰𝗵𝗶𝗻𝗴 is a…

Code reviews are about building, learning, and teaching. Not blaming. Here’s what the modern code review workflow looks like: 𝟭) 𝗖𝗼𝗱𝗲 ↳ Isolate changes by writing code on a separate git branch ↳ CodeRabbit already starts reviewing, flagging bugs, logic issues, and bad…

What is AI Gateway? As AI moves into production, most teams hit the same wall: Infra wasn’t built for this. Apps, agents, orchestration layers, and context layers are all talking to models in real time. And things get messy fast. Infrastructure often falls behind, with…