Backend & Infrastructure — Harbor Software Blog

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Authentication Patterns for Multi-Tenant SaaS Applications

Multi-tenancy adds a dimension to authentication that single-tenant applications do not have: you must not only verify who a user is, but also which tenant they belong to and what they are authorized to do within that tenant. Getting this wrong leads to the most

Integration Testing Strategies for Microservice Architectures

Microservices solve organizational scaling problems and create testing nightmares. When your application is a single deployable unit, an integration test can boot the whole thing, exercise a user journey, and verify the result. When your application is 15 services communicating via HTTP, gRPC, and message

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AI-Powered Content Summarization: Architecture and Trade-offs

Content summarization sounds simple: take a long document, produce a short version. In practice, building a summarization system that works reliably across document types, handles edge cases without hallucinating, respects length constraints consistently, and scales to thousands of documents per day is a genuine engineering

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Message Queues Compared: RabbitMQ vs Kafka vs Redis Streams

Every distributed system needs a message passing layer, and the choice between RabbitMQ, Kafka, and Redis Streams shapes your architecture in ways that are painful to undo later. We have deployed all three in production across 12 projects over the last 4 years, sometimes within

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Scaling FastAPI Applications: From Prototype to Production

FastAPI is the best Python web framework for building APIs in 2024. It combines type-safe request handling via Pydantic, automatic OpenAPI documentation, native async support, and performance that approaches Node.js for I/O-bound workloads. But most FastAPI tutorials stop at “hello world” and never address the

Real-Time Data Processing with Python: Lessons from SparkAI

Python is the default language for data processing, but most Python data pipelines are batch-oriented: read a file, transform, write results. When a client needed sub-second processing of streaming sensor data with AI inference at the edge, we had to rethink everything we knew about

Milvus vs Pinecone vs pgvector: Choosing a Vector Database

The Vector Database Decision If you’re building anything with embeddings — semantic search, RAG pipelines, recommendation engines, image similarity — you need somewhere to store and query vectors. The market has exploded with options, and the decision isn’t obvious. We’ve deployed all three of the

RAG Architecture Patterns: Beyond Basic Document Q&A

Every team building with LLMs eventually arrives at the same place: the model needs access to private data, and fine-tuning is either too expensive, too slow, or too rigid. Retrieval-Augmented Generation (RAG) is the answer most reach for. The problem is that most RAG implementations

Event-Driven Architecture with Python: A Complete Guide

Request-response is the default architecture for web applications, and for good reason. A client sends a request, a server processes it synchronously, and returns a response. Simple, predictable, easy to debug. This works beautifully for straightforward CRUD operations where a single action has a single