https://divypatel.in/blog Writing by Divya Patel, Backend & Cloud Engineer: practical guides on system design, AWS, Terraform, caching with Redis, CI/CD and self-hosted LLM infrastructure, with diagrams. en https://divypatel.in/blog/lambda-zero-downtime-deploys-github-actions https://divypatel.in/blog/lambda-zero-downtime-deploys-github-actions Tue, 03 Nov 2026 00:00:00 GMT Deploy AWS Lambda from GitHub Actions with no stored AWS keys: OIDC login, versions, a weighted alias canary and automatic rollback. AWS Lambda GitHub Actions CI/CD Terraform https://divypatel.in/blog/self-host-llm-vllm-cost-vs-api https://divypatel.in/blog/self-host-llm-vllm-cost-vs-api Tue, 27 Oct 2026 00:00:00 GMT A neutral break-even model for self-hosting an LLM with vLLM vs paying an API per token, with a worked example, real prices and a small production setup. LLM vLLM Cost AI infrastructure https://divypatel.in/blog/redis-cache-stampede-aurora https://divypatel.in/blog/redis-cache-stampede-aurora Tue, 20 Oct 2026 00:00:00 GMT Redis caching patterns for Postgres in plain words: cache-aside vs write-through, cache stampede prevention, TTL jitter and safe invalidation. Redis PostgreSQL AWS System design https://divypatel.in/blog/terraform-aws-startup-layout https://divypatel.in/blog/terraform-aws-startup-layout Tue, 13 Oct 2026 00:00:00 GMT How to structure Terraform for a small AWS startup: one state, then split state per stack and environment, then multi-account. With real HCL. Terraform AWS Infrastructure as Code DevOps