Sai Sampath Lanka
Full Stack Developer
I build web applications, mostly backend, APIs, data, and the systems behind them.
I write about engineering problems I am solving.
Reading
Designing Data-Intensive Applications
Experience
Sep 2023 — Jun 2025Junior Software Developer·WizardTales Private Limited
Built a Fastify based Email Template Service to generate 25+ transactional and marketing email templates (auth, onboarding, billing, service updates). Designed the sanitization layer myself: a two-library defense-in-depth (sanitize-html + xss) to safely handle externally-supplied data before it reaches Handlebars rendering.Built the backend exchange-rate service for Multi-Currency Pricing Calculator (scheduled fetch/cache within a free tier API'rate limits) and the frontend conversion layer, a reusable Vue directive that reactively converts and formats prices app wide using the Intl API.Owned the frontend for an internal identity/access-management console modeled on Keycloak: session-gated routing, role and group management UI, OIDC provider configuration, admin event tracking and built against an API contract from our backend engineer.Part of a 3-person migration of our marketing site to Nuxt for SEO with route level rendering strategy, i18n routing with proper canonical/hreflang handling, and dynamic SEO metadata sourced from our CMS.
Projects
- Uptime Pulse
A production grade API uptime monitoring system built with Node.js, TypeScript, and Fastify. Schedules HTTP health checks via BullMQ, detects consecutive failures, fires realtime alerts via Server Sent Events, and auto resolves when services recover.
- Distributed Job Queue System
A distributed asynchronous job processing system designed to handle concurrent workloads reliably using Redis queues, worker orchestration, retry mechanisms, dead-letter queues, and failure recovery workflows.