https://shivamrastogi.com/tech/ Recent content in Tech on Shivam Rastogi Hugo -- gohugo.io en-US Copyright © 2026, Shivam Rastogi Thu, 09 Apr 2026 00:00:00 +0000 https://shivamrastogi.com/tech/over-engineering-an-async-ai-voice-chat-app-on-purpose/ Thu, 09 Apr 2026 00:00:00 +0000 https://shivamrastogi.com/tech/over-engineering-an-async-ai-voice-chat-app-on-purpose/ This is an async AI voice chat app. You record a voice message, send it to a friend, they listen and reply when they’re ready. In the background, OpenAI Whisper transcribes the audio and a separate service handles image processing. Conceptually, it’s a ten-line Django view with a file upload and a row in a message table. That’s not what I built. What I built is seven repos, four languages, Apache Pulsar running on Amazon EKS with end-to-end TLS, a Spring Boot image service, a Python Whisper transcription consumer, a Django web app deployed to ECS Fargate behind an AWS CDK CodePipeline, and a cert-manager setup issuing certificates from AWS Private CA to every pod in the cluster. https://shivamrastogi.com/tech/fixing-duplicate-deadline-callbacks-in-airflows-ha-scheduler/ Mon, 06 Apr 2026 00:00:00 +0000 https://shivamrastogi.com/tech/fixing-duplicate-deadline-callbacks-in-airflows-ha-scheduler/ Apache Airflow supports running multiple scheduler replicas for high availability. The idea is simple — if one scheduler dies, another takes over. No downtime, no lost work. Most of Airflow’s critical paths (DAG parsing, task scheduling, trigger processing) are carefully designed to coordinate safely across replicas using row-level locks. Most of them. Last week I shipped a fix for one that wasn’t. The scheduler’s deadline-check loop was missing a FOR UPDATE lock, which meant two schedulers could pick up the same expired deadline at the same time and fire the breach callback twice.