Backend Development

Backend development is the server-side work behind an application: APIs, business logic, databases, queues and background jobs. Backend engineers pick languages such as Java, Python, Node.js or C#, decide how data is stored and how services talk to each other, and keep it all fast and correct under load. Most of the hard calls are trade-offs, such as SQL against NoSQL or a monolith against microservices.

177 articles

07/06/2025 11 min read

Mockito: Mocking, Stubbing, and Verifying

Executive Summary: Mockito lets you replace a class’s dependencies with mocks, stub their responses, and verify the calls…
10/05/2025 10 min read

JUnit 5: Writing Your First Tests

Executive Summary: A JUnit 5 test is a method annotated @Test that passes when its assertions hold. I…
27/03/2025 6 min read

Code Optimization in Java: Minimize Latency with Profiling

Java latency playbook: allocation and I/O techniques, pooling, async-profiler and JMH guidance, with before/after discipline.
19/03/2025 22 min read

LLM App Production Checklist: Cost, Caching, Retries, and Safety

Eleven practices that keep an LLM feature alive in production, ranked by impact, each with a wrong example,…
23/02/2025 11 min read

Profiling and Performance Tuning Basics in Java

Executive Summary: Java performance tuning works best as a loop: reproduce under steady state, set a baseline, profile,…
19/02/2025 17 min read

How to Test and Evaluate LLM Applications in Python

Separate deterministic tests from evals, build a golden dataset, score with code before judges, and read pass rates…
15/01/2025 15 min read

How to Build an MCP Server in Python

Expose your own tools and data to AI assistants through the Model Context Protocol: a complete Python server,…
11/01/2025 13 min read

Garbage Collection in Java: Generations, Collectors, and Tuning

Executive Summary: Java garbage collection reclaims objects no GC root can reach and organizes the heap by age…
21/12/2024 12 min read

JVM Memory Areas and Class Loaders: Heap, Stack, Metaspace, and Execution

Executive Summary: When java Main runs, class loaders load your code, the JVM stores data in distinct memory…
21/11/2024 7 min read

Dependency Injection in Spring Boot

Constructor injection, circular dependencies, and advanced Spring Boot DI scenarios with concrete code patterns.
17/11/2024 12 min read

Practice: Build a Concurrent Downloader in Java

Executive Summary: This practice project builds a concurrent link checker in Java two ways: a fixed thread pool…
13/11/2024 16 min read

Structured Output from LLMs in Python with Pydantic

Turn model replies into validated Python objects: one Pydantic schema, schema-constrained generation where available, and a repair loop…
26/10/2024 12 min read

Structured Concurrency in Java

Executive Summary: Structured concurrency ties subtasks to the scope that started them, so failures and cancellations do not…
16/10/2024 14 min read

Python 3.13 Free-Threading and JIT: What Changed and Should You Care

Python 3.13 ships an optional build without the GIL and an experimental JIT. Learn what each one does…