Technical Stack & Architecture

Battle-Tested Engineering Capabilities

Every tool and methodology in this matrix was selected for verified uptime, security, and measurable performance. Backed by automated test harnesses and live production experience.

Backend & Systems Engineering

Resilient microservices, idempotent transaction handlers, and background workers.

Node.js, TypeScript & PythonPrimary runtimes for asynchronous microservices, task daemons, type-safe domain models & contract interfaces

Next.js 15 & 16 (App Router)SSR, React Server Components, streaming, and edge route handlers

Express.js & WebSocketsHigh-performance routing, custom middleware pipelines & real-time WS servers (ws 8.20)

Idempotency PatternsDistributed lock keys (SETNX) preventing duplicate webhook execution & race conditions

Zero-Loss WebhooksCryptographic HMAC-SHA256 signature verification and background ledger reconciliation

DNS MX Routing & DomainsMulti-domain email routing (smtp.catchmail.io MX) and programmatic DNS configuration

Vanilla JS / Zero BloatHigh-performance <30KB web utilities (Vite 8) delivering instant cold loads without runtime weight

Case Study: 28KB Ingress Platform Field Note: 28KB Email Engine

VPC Security, Firewalls & Payment Proxy

Air-gapped database environments, strict firewall rules, and hardened payment proxies.

Private VPC DB IsolationMongoDB bound exclusively to non-public subnets with zero 0.0.0.0 exposure

UFW Static IP WhitelistingPacket filtering allowing port 27017 ingress exclusively from app server static IP

Payment Gateways & Dual RailsProduction integrations for Stripe (Elements & Webhooks), SSLCommerz, EPS, UddoktaPay, bKash & Nagad

Hardened Payment ProxyReverse proxy validating checkout requests & webhooks before internal database commits

CVE Incident RemediationZero-day RCE remediation (React2Shell CVE-2025-55182) without database loss or downtime

Docker Resource CappingStrict CPU/RAM container limits preventing rogue processes from freezing host servers

Case Study: React2Shell Incident Field Note: Air-Gapping MongoDB

Marketing Engineering & Server-Side Tracking

Bypassing browser ad-blockers and iOS ATT restrictions for 100% conversion attribution.

Server-Side GTM (sGTM)Dedicated server container architecture hosted on Stape for server-to-server tracking

Meta Conversions API (CAPI)Direct server event dispatch bypassing Safari ITP and browser privacy extensions

Deterministic Event DedupUnique event_id generation matching browser pixel & server CAPI with 0 double-counts

E-Commerce DataLayerCapturing view_item, add_to_cart, begin_checkout, and purchase events into GA4

PII Cryptographic HashingClient-side normalization and SHA-256 cryptographic hashing of customer data

Case Study: sGTM & Meta CAPI Field Note: CAPI Deduplication Guide

AI, Python & Enterprise Automation

Python automation daemons, Telegram bots, browser scraping, and self-hosted microservices.

Python Automation & Telegram BotsAsynchronous Python engines (aiogram, Telethon), multi-account task bots & background daemons

Headless Browser AutomationPlaywright, Selenium & anti-bot bypass pipelines for dynamic DOM extraction and automated workflows

Universal API AutomationReverse-engineering private endpoints, OAuth/HMAC signing, and high-throughput async request workers

Proprietary Workflow EnginesCustom Python & Node.js/Prisma microservices eliminating recurring SaaS vendor tax (Zapier/n8n)

Omnichannel Social BotsMeta Graph API (FB Messenger, Instagram DM), Telegram, and TikTok automated conversational agents

Self-Hosted n8n & DockerDedicated webhook pipelines, queue runners, and private enterprise task automation

Structured LLM OrchestrationDeterministic JSON schema generation enforced via strict Zod & Pydantic validation

Case Study: QuickMation Engine Field Note: Proprietary AI vs SaaS Tax

Databases, Multi-Tier Caching & Cloud

Sub-millisecond read paths, structured schema design, and secure asset vaults.

Redis (ioredis 5.8 & 5.10)Multi-tiered caching (L1/L2), distributed locks, session vaults & rate limiters

PostgreSQL & Prisma 7.8Relational data modeling, ACID transactions, and connection pool management

MongoDB & Mongoose 8/9Document schema design, aggregation pipelines, and atomic conditional updates

AWS S3 & Cloudflare R2Presigned URL generation, anti-leech token vaults & global media distribution

Singleflight CoalescingEliminating cache stampedes and thundering herd problems during peak spikes

Case Study: Redis Caching Fabric Field Note: Singleflight 22ms P99

Automated Testing & Reliability Harness

Financial ledger correctness, continuous integration gates, and zero-regression deployments.

Vitest & JestAutomated unit test suites for pricing algorithms, auth guards & domain logic

Supertest Integration TestsEnd-to-end HTTP integration tests for webhook ingestion & checkout APIs

GitHub Actions CI/CDAutomated CI pipelines: linting, type-checking & test runners on every Pull Request

Docker Test ContainersSpinning isolated Redis and Mongo instances in CI runners for deterministic tests

Branch Protection & PR GatesStrict status checks enforcing test passes before production deployment

Case Study: Idempotent Payment Testing

Standard Operating Procedure

Production Quality Standards on Every Deployment

Before any service is labeled operational, it must pass these non-negotiable architectural gates:

Air-Gapped Private DB

MongoDB bound to private subnet; UFW whitelists only app server static IP on port 27017.

Hardened Payment Proxy

Client-side never communicates secrets; reverse proxy cryptographically signs and validates webhooks.

Server-Side Tracking (CAPI)

sGTM + Stape container dispatching server-to-server conversions with unique event_id deduplication.

Automated Test Gate

Vitest unit & Supertest integration suites must pass on CI before merging PRs.

Container Resource Capping

Docker CPU/memory constraints preventing runaway processes from freezing the VPS host.

Process Auto-Healing

PM2 / systemd watchers restarting hung or memory-leaking processes in <1s.