~/init_sys

Backend Projects + System Design

Real systems with architecture choices, component boundaries, tradeoffs, and measurable business outcomes.

HR and Payroll Infrastructure

[PROD]

Automated HR exits, payroll, and reporting workflows for multi-stakeholder operations with reliability and auditability.

Problem Context

Legacy and manual workflows consumed significant HR bandwidth, introduced coordination bottlenecks, and delayed operational outcomes.

Solution Strategy

Built event-driven backend services and workflow automation pipelines with clear state transitions, notifications, and observability hooks.

Tech Stack

[Node.js][AWS Lambda][Google Apps Script][PostgreSQL][Docker]

System Design Pattern

Event-Driven Workflow Automation

Workflow API

Accepts events and orchestrates domain-specific workflows.

Node.js + AWS Lambda

Scheduling Engine

Finds common availability and schedules calls with reminder support.

Custom Scheduler + Notification Handlers

Reporting Pipeline

Aggregates monthly summaries and sends stakeholder reports.

Gemini API + Email Integrations

Key Decisions

  • >Used event-driven boundaries to isolate high-change business workflows.
  • >Kept idempotent handlers for retry-safe notifications and payroll steps.
  • >Started low-cost with Apps Script, then migrated critical paths to Lambda.

Tradeoffs

  • >Higher initial design complexity for better long-term maintainability.
  • >Added queueing and workflow state management to avoid silent failures.

Project Media

No media attached yet. Add screenshots or architecture diagrams in public/projects and map them in project data.

Business Impact

60-70%

Operational Reduction

Reduced manual coordination and repetitive HR operational work.

70%

Payroll Workflow Reduction

Automated core payroll calculations and distribution tasks.

30%

Payslip Distribution Savings

Reduced manual distribution effort and improved cycle speed.

JobLead: AI Job Matching Platform

[PROD]

Resume-to-job matching platform using vector search and async pipelines for scalable candidate relevance scoring.

Problem Context

Manual matching between resumes and roles was slow, inconsistent, and difficult to scale as job volume increased.

Solution Strategy

Implemented parsing and matching pipelines with vector-backed scoring and asynchronous workers for ingestion and ranking.

Tech Stack

[FastAPI][PostgreSQL][pgvector][Redis][Celery][Docker]

System Design Pattern

Asynchronous Scoring Pipeline

Ingestion API

Receives jobs and resumes, validates payloads, and stores normalized records.

FastAPI

Vector Matching Service

Computes semantic relevance across resumes and role descriptions.

PostgreSQL + pgvector

Async Worker Layer

Processes scraping, parsing, enrichment, and score recomputation.

Celery + Redis

Key Decisions

  • >Separated API request latency from ranking workloads via background jobs.
  • >Used vector search to improve semantic relevance over keyword-only matching.

Tradeoffs

  • >Async processing introduces eventual consistency between ingest and final score.
  • >Higher infrastructure complexity compared to synchronous scoring.

Project Media

No media attached yet. Add screenshots or architecture diagrams in public/projects and map them in project data.

Business Impact

Automated

Pipeline Execution

Automated job scraping and resume parsing pipeline.

High Accuracy

Matching Quality

Improved role-candidate relevance with vector scoring.

Scalable

Processing Throughput

Moved expensive matching work to async workers and queues.

eNoting: Cloud Notebook API

[PROD]

Secure note management API with JWT and passwordless WebAuthn support, plus production-ready API documentation.

Problem Context

Needed a secure backend-first notebook system with modern auth and clear developer onboarding.

Solution Strategy

Built RESTful services with robust authentication flows and complete API documentation for consumers.

Tech Stack

[Node.js][Express][JWT][WebAuthn][Swagger/OpenAPI]

System Design Pattern

API-First Secure Service

Auth Service

Handles token issuance, verification, and auth guards.

Express + JWT

Credential Module

Enables passwordless registration and login challenges.

WebAuthn

Documentation Layer

Maintains API discoverability and contract visibility.

Swagger/OpenAPI

Key Decisions

  • >Used API-first contracts to keep clients and backend in sync.
  • >Adopted passwordless auth to improve security posture.

Tradeoffs

  • >WebAuthn requires stronger client/browser compatibility handling.

Project Media

No media attached yet. Add screenshots or architecture diagrams in public/projects and map them in project data.

Business Impact

Secure

Authentication

Implemented JWT and WebAuthn-based passwordless flows.

Reliable

API Design

Built clear resource boundaries and token-protected endpoints.

Developer Ready

Documentation

Published discoverable Swagger/OpenAPI references.