Secure Your APIs: OAuth2 and JWT for Beginners
Secure Your APIs: OAuth2 and JWT for Beginners APIs are frequent targets for bad actors since they expose data and functionality. Securing them whil…
Testing & QA
⚑ Report a ProblemLatest Testing & QA news from Tech News
All topics
agents
ai
api
architecture
automation
backend
beginners
career
claude
cybersecurity
devchallenge
devops
discuss
javascript
llm
machinelearning
mcp
node
opensource
performance
productivity
programming
python
security
showdev
softwareengineering
testing
tutorial
typescript
webdev
Building an Excel download API with TBEG and Spring Boot (Kotlin/Java)
In Part 3 , we explored TBEG's template syntax in depth. Now let's build an Excel download API with Spring Boot + TBEG - the most common real-world…
Spring Boot 3.5 Stopped Getting Patches in June. Don't Migrate to 4.0.
Two dates decide your next few weeks of Spring work: 30 June 2026 — Spring Boot 3.5 stopped getting free patches. 3.5.16 was the last one. 31 Decemb…
Building a Full RAG Pipeline in Spring Boot — From Ingest to Grounded Answer
Previous articles covered the individual pieces of RAG. You now know what embeddings are, how to chunk documents, and how Pinecone stores and search…
Role-Based and Permission-Based Access Control in Spring Security
Introduction Once authentication is solid, the next question is inevitable: what is this user actually allowed to do? Authentication proves who you…
The Database Tells You What Is. An Audit Trail Tells You What Happened
Something is wrong with a customer's account. You open the database and run: SELECT * FROM customer_account WHERE id = 12345 ; The row looks perfect…
You Might Not Need a Vector Database
A RAG pipeline is a lot of parts: a chunker, an embedding model, a vector database, a retriever, usually a reranker, and an eval harness to tell you…
If Your Spring AI Streams Die After 60 Seconds, It's Not Your Network
If you're on Spring AI 2.0.1 and your streaming calls die after about a minute with OpenAIIoException: Stream failed , stop debugging your proxy. Si…
Eliminating Race Conditions in Clustered Spring Boot with PostgreSQL Advisory Locks
It’s 02:14 AM. Your alert manager fires: an account balance dropped below zero, or a user received two trial credits instead of one. You trace the l…
I Removed an API Field. Hindsight Found Who Still Needed It.
API compatibility problems are rarely difficult because removing a field is technically hard. The difficult part is knowing who still depends on tha…
Your Search Query Is a Program: Composing Role-Based SQL With the Strategy Pattern
Every business application has this screen somewhere: a table of records, filter boxes above it, and a user who may only see part of the data. The f…
One Missing WHERE Clause Can Expose Another Customer’s Data
A customer opens their dashboard and sees another company’s invoices. Nobody needed to break in. An endpoint returned data it should never have retu…
Transactional Outbox Pattern: Memory Queue for Speed, PostgreSQL for Recovery
In distributed systems, the Transactional Outbox Pattern is a common way to reliably publish events after a database transaction. The idea is simple…
Nexus Core v1.7.0: Moving from MongoDB-Centric to Multi-Database Architecture
Nexus Core v1.7.0: Moving from MongoDB-Centric to Multi-Database Architecture Today I released Nexus Core v1.7.0 , and this is one of the most impor…
The /actuator/env Sanitizer Doesn't Know Your Naming Conventions
I recently wrote about allowlisting actuator endpoints : what to expose and what not to. One question stayed open and kept nagging at me: if you dec…
Why I Publish to Kafka Only After the Transaction Commits
The bug that doesn't show up in tests — and what to do about it There is a class of bug in event-driven systems that is almost invisible in developm…
Beyond Heavy API Keys: How I Built a Zero-Cost Asynchronous AI Summarizer in Spring Boot 3.4
🚀 Introduction When building cloud services around Generative AI, developers often face two major challenges: High Latency & Thread Exhaustion:…
Week 11 of #100DaysOfCode: Learning and Building Microservices with Spring Boot
Introduction This week has been another challenging but rewarding part of my #100DaysOfCode journey. I moved from learning Microservices Architectur…
I Found a P0 Auth Bypass by Testing What null Does to BCrypt
While building SCIP — a supply chain platform with 90+ Spring Boot REST endpoints — I was boundary-testing the auth flow when I noticed something th…
What Every Java SaaS Backend Keeps Rebuilding — and How to Structure It Once
Starting a new SaaS product is exciting until you realize how much work happens before you can build the feature that actually makes the product uni…
The Outbox Pattern Is Not Enough
The textbook version of the transactional outbox is tight. You save the domain entity and an outbox row in one local transaction. A background sched…
Why Your JPA Counter Column Keeps Resetting to Zero
This article was originally published on Jo4 Blog . I'll cut to the chase: if you have a counter column, a @Modifying @Query that increments it, and…
Building AI Prompt Lab with Java 21, Spring Boot and React 19
AI Prompt Lab is a full-stack application I built around a simple idea: managing reusable AI prompts should feel like working with any other structu…
Building a Production AI Agent in Spring Boot: The Sandbox Rule (Part 11)
Docker shipped a product this week with a feature it calls YOLO mode, and the marketing line is almost a dare: "No manual review, no permission prom…
Your Spring AI tests are slow, flaky, and cost money. Here's how to make them deterministic.
You wire up Spring AI, the ChatClient fluent API feels great, your feature works. Then you sit down to write a test — and every good option is bad.…
Building a Production AI Agent in Spring Boot: The Supervisor Pattern with Specialist Agents (Part 5)
"Can I return the blue jacket and use the store credit to order the same one in a large?" The tester from Parts 2, 3, and 4 again. That one sentence…
Building a Production AI Agent in Spring Boot: Conversation Memory and Context (Part 2)
Two weeks after I shipped the e-commerce agent from Part 1, my first real tester asked it a question that broke the illusion: "What was in my cart a…
Building a Production AI Agent in Spring Boot: Tools and Function Calling
tags: [java, springboot, ai, springai] Six months ago, I added an AI assistant to an e-commerce platform I was building. The idea was simple: let us…
Building a Multi-Agent Hiring Workflow with LangChain4j and LangGraph4j on Spring Boot
I wanted to actually learn LangChain4j and LangGraph4j beyond the "hello world" chat example, so I built something with enough moving parts to force…
I built a "real job" simulator for Spring Boot learners, free & open source
Most Spring Boot tutorials teach you to build a CRUD app and call it a day. But that's not really what the job looks like day to day, so I put toget…