System Desgin
Local Document Q&A Agent with LlamaIndex.js & Next.js
TL;DR – Local RAG avoids data leakage and cuts per‑query costs. – Next.js 14’s App Router pairs nicely with LlamaIndex.js for end‑to‑end pipelines. – Choose…
// author
Nilesh Raut
’m Nilesh, a Software Development Engineer with 2+ years of experience, specializing in Go, JavaScript, Python, Docker, Kubernetes, Git, Jenkins, microservices, and system design (LLD/HLD), backed by a strong foundation in data structures and algorithms. Alongside my engineering journey, I bring 4+ years of hands-on experience in SEO, where I’ve worked extensively on content strategy, keyword research, technical SEO, and organic growth, helping products and businesses scale efficiently by aligning solid technology with search-driven performance.
314 articles
leet code
Debugging gRPC Connection Timeouts in Microservices
TL;DR – gRPC deadline is an absolute end‑time; a timeout is a relative network limit. – Propagate deadlines through each hop; never let a…
System Desgin
Orchestrate Multi‑Step LLM Workflows with Node.js & CrewAI
💡 Pro Tip: If you ever watched an LLM “hallucinate” in a production ticket‑routing system, you know the pain of hand‑off failures. The story…
leet code
Zero‑Downtime Database Migrations in Kubernetes
TL;DR – Quick Takeaways Treat schema changes like feature rollouts: use blue‑green or canary patterns and guard every step with feature flags. Dual‑write +…
System Desgin
Debugging LLM Agent Hallucinations in JavaScript Apps
⚡ Opening Hook When a shopping‑cart bot on nileshblog.tech suggested a “premium banana‑infused Bluetooth speaker” to a customer, the order blew up the checkout pipeline.…
leet code
Service Mesh vs API Gateway for Go Backends – Key Insights
TL;DR – Service Mesh shines for east‑west traffic, while an API gateway is the front door for north‑south requests. – A sidecar proxy adds…
System Desgin
Implement AI Agents with LangChain.js – Beginner Guide
TL;DR – LangChain.js lets you stitch LLMs, tools, and memory into a single runnable agent. – You only need Node ≥ 18, an OpenAI API key,…
System Desgin
AI Code Reviewer in GitHub Actions: 2026 Guide
TL;DR – Native GitHub CodeQL misses semantic bugs that LLMs can spot. – Choose between local LLM inference and managed API with a decision…
leet code
Designing Microservices Caching with Redis Write‑Through
TL;DR – Write‑through keeps Redis and the primary DB in lockstep, eliminating most stale‑read bugs. – Double‑write adds 2‑5 ms latency per write, but you…
leet code
Optimizing Kafka for High‑Throughput Logging in Go
TL;DR – Use Sarama v1.44 async producer, not sync, for log fire‑and‑forget. – Set batch.size ≈ 1 MiB and linger.ms 5‑10 ms; this alone can lift throughput 30‑40×.…
leet code
Git Fetch vs Pull vs Rebase: When and How to Use Each
⚡️ Opening Hook Last month a senior engineer on the nileshblog.tech team pushed a hotfix, but the deployment crashed because the CI pipeline merged…
leet code
Tuning Persistent Volumes in Stateful Kubernetes
“Our production PostgreSQL pod started lagging at 5 seconds per query. The CPU stayed idle, the network was clean, but the latency exploded.” That anxiety‑inducing…
leet code
Implement Circuit Breakers in Python Microservices – Guide
TL;DR – Circuit breakers isolate flaky downstream calls, turning cascading failures into fast‑fail responses. – A bare‑bones Python class can manage CLOSED, OPEN, and…
leet code
AI in Human Life: Building Reliable Production Systems
In the fall of 2020, a medical AI system trained to spot signs of stroke on CT scans was rolled out across a European…
AI
How to Run LLMs Locally and Reduce AI Model API Costs
Learn how to run LLMs locally using Ollama, Open WebUI, DeepSeek, Qwen, and VS Code to reduce Claude/OpenAI API costs.
Backend Dev
From PR to Production: How Kubernetes Deployments Actually Work (Single Service + Microservices in the Real World)
Most developers know how to write code. Fewer understand what actually happens after they click “Merge Pull Request.” And even fewer truly understand what…
Backend Dev
Why Your Node.js App Is Fast Locally but Slow in Production
A senior engineer’s deep dive into performance illusions, real bottlenecks, and hard-earned lessons If you’ve shipped a Node.js service to production, you’ve almost certainly…
Backend Dev
Idempotency Explained: How to Design Safe APIs That Don’t Break in Production
Idempotency is one of those topics that looks simple on paper and brutal in production. Most engineers understand the definition. Fewer understand the failure…