---
title: "Kaustubh Poshiya (@kaustubhposhiya) | Hashnode"
description: "Kaustubh Poshiya (@kaustubhposhiya) writes on Hashnode. Read their latest articles and follow their work."
url: "https://hashnode.com/@kaustubhposhiya"
---

@kaustubhposhiya

# Kaustubh Poshiya

@kaustubhposhiya · Joined January 2026

### [Blue-Green Deployment for Legacy Applications on AWS EC2: A Complete Guide](https://kaustubhposhiya.hashnode.dev/blue-green-deployment-for-legacy-applications-on-aws-ec2-a-complete-guide?utm_source=hashnode&utm_medium=feed)

Introduction Zero-downtime deployments are often considered a luxury reserved for cloud-native or containerized applications. In reality, many organizations still rely on legacy applications running directly on EC2 instances—applications that were ne...

7 min read · [kaustubhposhiya.hashnode.dev](https://kaustubhposhiya.hashnode.dev/blue-green-deployment-for-legacy-applications-on-aws-ec2-a-complete-guide?utm_source=hashnode&utm_medium=feed)

[Dec 5, 2025](https://hashnode.com/posts/blue-green-deployment-for-legacy-applications-on-aws-ec2-a-complete-guide/696f492a75cd854da7cdc02d)

### [Zero-SSH Infrastructure: Building Secure Access with AWS SSM Session Manager](https://kaustubhposhiya.hashnode.dev/zero-ssh-infrastructure-building-secure-access-with-aws-ssm-session-manager?utm_source=hashnode&utm_medium=feed)

Introduction: Why SSH Became a Liability SSH has been the default way to access servers for decades. It’s familiar, powerful, and deeply ingrained in how engineers work. But in modern cloud environments, familiar doesn’t always mean secure. A few yea...

5 min read · [kaustubhposhiya.hashnode.dev](https://kaustubhposhiya.hashnode.dev/zero-ssh-infrastructure-building-secure-access-with-aws-ssm-session-manager?utm_source=hashnode&utm_medium=feed)

[Aug 22, 2025](https://hashnode.com/posts/zero-ssh-infrastructure-building-secure-access-with-aws-ssm-session-manager/696f5a1e4aa6ff36d4b59624)