If you mostly live in .NET, the Java platform can look like a parallel universe: JVM, JDK, JARs, app servers, bytecode. The useful shortcut is to map each concept back to something you already know from C# and the CLR. This guide is a translation layer for .NET developers: what the JVM is, how the JDK compares to the .NET SDK, and what your real options are when a C# system needs to work with Java
Multi-tenancy is the economic engine of SaaS. Sharing infrastructure across customers reduces cost and simplifies operations. But it introduces a risk that can end your business overnight: tenant data leakage. When one customer can see another customer's data — even accidentally — the consequences are severe. Regulatory fines, contract termination, public disclosure requirements, and irreparable t
Originally published at hafiz.dev Every SaaS app eventually hits the same question: how do you make one application serve multiple customers with separate data? If you're building with Filament, the answer is closer than you think. Filament ships with a built-in tenancy system that handles tenant switching, automatic resource scoping, registration, and profile management out of the box. But here's
The API Rate Limit Catastrophe In modern B2B SaaS development at Smart Tech Devs, your application rarely lives in isolation. You constantly communicate with external services: billing via Stripe, CRM syncing via Salesforce, or email campaigns via Resend. The architectural trap occurs when you combine the immense speed of Laravel Queues with the strict rate limits of these third-party APIs. If you
💡 Problem: How do we ensure that a class has only ONE instance throughout the application? 💡 Common Use Cases: Logger Configuration Manager Database Connection 💡 Approach: We restrict object creation and provide a global access point. 💡 Key Idea: Private constructor Static instance Public method to access it 💻 Java Example: private static Singleton instance; privat
The drift problem Every project that ships a translated README has the same lifecycle: Someone writes README.md in English. A contributor opens a PR with README.zh.md. Great. Three months later, English has six new sections. Chinese has the original. A second translator opens README.es.md. Spanish gets translated from… which version? The current README.md? Or README.zh.md, by accident, because t
Apache Stateful Functions is one of the quietly powerful frameworks in the Flink ecosystem - durable per-key state, exactly-once messaging, polyglot remote functions, all on top of Apache Flink. It's also been functionally dormant since October 2024, and it doesn't run on Flink 2.x. We needed it on Flink 2.x. So we maintained the continuation: kzmlabs/flink-statefun. This post is the why and the h
How We Improved Payment System Throughput by 25% Using Apache Kafka at a Fortune 500 FinTech By Disha Sune — Java Backend Engineer | Spring Boot | Kafka | AWS | Fiserv At Fiserv, our payment processing platform handled millions of financial transactions daily for 600+ enterprise clients including McDonald's, Google, and Domino's. As transaction volumes grew, our legacy synchronous REST API archi