Product engineering for the web

We build commerce and content platforms that run at scale.

SunReign Tech is a product-engineering studio. We design, build and harden WordPress and React systems that serve millions of sites — then we stay on to keep them fast, secure and shippable.

Start a projectSee our work
2M+
sites running code we've shipped
100K+
businesses on platforms we build
7+
years shipping production software
70K+
live stores in a single rollout

What we do

Six things we do properly.

We are deliberately narrow. Everything below is work we have shipped into production at scale — not a service list we hope to grow into.

01

WordPress Websites

Custom-built WordPress sites — not templates. Design-to-code implementation, custom themes, and a content model your team can actually run.

  • Custom theme development from Figma, pixel-accurate and responsive
  • Full Site Editing, block themes and Customizer-driven design systems
  • Content architecture: custom post types, taxonomies and meta
  • WooCommerce storefronts, checkout and product templates
  • Multilingual, RTL and WCAG-accessible markup across 45+ locales
  • Migrations, replatforming and version upgrades without downtime

02

Plugins & Gutenberg Blocks

Product-grade WordPress engineering: plugins, custom React blocks and block libraries built to WordPress Coding Standards.

  • Custom React blocks, editor panels and sidebar plugins
  • Interactivity API, dynamic render callbacks, conditional asset loading
  • Plugin architecture in PHP 8 (OOP/MVC), Composer, PSR-4
  • Backward-compatible migrations for installed bases in the tens of thousands
  • Page-builder compatibility: Elementor, Beaver Builder
  • Distribution-ready code: PHPCS/WPCS, i18n, documentation

03

React & TypeScript Front-Ends

Component-driven application UIs, shared design systems, and the state architecture to keep them coherent as they grow.

  • React 19 and Next.js App Router in TypeScript
  • Design systems and shared component libraries (Storybook)
  • Redux Toolkit, Context and predictable state at scale
  • Complex forms, routing, data fetching and REST integration
  • Jest, React Testing Library and Playwright end-to-end coverage
  • Accessibility built in, not retrofitted

04

Headless & Commerce

Storefronts, checkouts and dashboards over external commerce backends, wired to the payment, shipping and CRM systems you already use.

  • Headless/decoupled WordPress and API-driven storefronts
  • Checkout, subscription and order-management interfaces
  • REST and webhook integrations: payments, shipping, CRM, martech
  • SDK development for third-party consumers
  • Token/JWT authentication flows and session handling
  • Data-flow and authentication troubleshooting across systems

05

Application Security

A security practice, not a checkbox. We find client-side and server-side vulnerabilities, fix them properly, and prove it with regression tests.

  • OWASP-aligned review: XSS, SQL injection, IDOR, auth bypass
  • Sanitization, escaping, nonces and capability checks
  • Vulnerability remediation with regression test coverage
  • Authentication, session and access-control review
  • Security-focused code review and developer guidance
  • Dependency and vulnerable-plugin auditing

06

Performance & Reliability

Core Web Vitals that hold up under real traffic, and a deployment pipeline that makes shipping boring.

  • Core Web Vitals and Lighthouse remediation
  • Object, transient, page and CDN caching (Redis, Cloudflare)
  • Query optimization, payload reduction, code splitting
  • CI/CD with GitHub Actions; staging, production and rollback
  • Managed enterprise hosting — WordPress VIP certified
  • Uptime, health and error monitoring (Sentry)

Selected work

Systems in production, not screenshots.

Client and platform names are withheld under confidentiality. The scale, the engineering and the outcomes are exactly as delivered.

Headless commerce platform100,000+ businesses

Re-architected a flagship product listing to 70,000 live stores

A monolithic product-listing system had become the bottleneck for an e-commerce platform serving six figures of merchants. We decomposed it into deeply nested, reusable child blocks — product card, filters, search, sort, pagination — each with instance-isolated state, and shipped a backward-compatible migration.

Outcome

  • Rolled out to 70,000+ live stores with zero reported issues
  • Modular components replaced a single unmaintainable unit
  • Existing merchant configurations migrated automatically
  • React
  • TypeScript
  • WordPress Interactivity API
  • PHP 8
WordPress block library35+ blocks

A React component library for the WordPress editor

We led a five-engineer team building an advanced block library — 35+ blocks, editor extensions and template kits — setting the component architecture, coding standards and review process behind it.

Outcome

  • 30% front-end performance gain via conditional asset loading
  • Reusable component architecture across the whole library
  • Accessibility and performance budgets enforced in review
  • React
  • JSX
  • PHP render callbacks
  • SCSS
WordPress theme1M+ active installations

A performance-first theme used on a million sites

Front-end ownership of a WordPress theme with over a million active installations and 6,000+ five-star reviews: Customizer controls, layout and typography systems, header and footer modules, and WooCommerce templates.

Outcome

  • Measurable page-load and Core Web Vitals improvements
  • Translation-ready, RTL-compatible markup across 45+ locales
  • Compatibility maintained across every major page builder
  • PHP
  • JavaScript
  • SCSS
  • WooCommerce
Full-stack buildReference project

MiniStore — an end-to-end commerce reference build

A complete storefront built to demonstrate our stack end to end: a typed Next.js front end over a Storybook design system, with a Python service and a relational data layer behind it, gated by CI.

View the live build

Outcome

  • React 19 / Next.js front end with Redux Toolkit and Auth.js JWT
  • FastAPI service over PostgreSQL with Prisma
  • Jest + RTL suites gating a GitHub Actions pipeline
  • Next.js
  • TypeScript
  • FastAPI
  • PostgreSQL
  • Prisma

How we work

Predictable, because the hard thinking happens first.

Most project failures are decided before any code is written. We spend the time up front so the build itself is uneventful.

  1. 01

    Scope & estimate

    We research before we build. You get a written scope, a realistic estimate, and an honest read on what is and isn't worth doing.

  2. 02

    Architect

    Component boundaries, data flow and migration strategy get decided before the first line of feature code — that's what makes the build predictable.

  3. 03

    Build & test

    Shipped to standards, with Jest, React Testing Library, Playwright and PHPUnit coverage, static analysis, and review on every change.

  4. 04

    Ship & maintain

    CI/CD across staging and production with rollback, monitoring in place, and documentation your team can pick up and run with.

About

A studio built around deep engineering, not headcount.

SunReign Tech is small on purpose. You work directly with the engineer who architects your system — no account layer, no handoff to a junior team.

RB

Rajkiran Gajanan Bagal

Founder & Chief Executive Officer

M.Sc. Computer Science
Savitribai Phule Pune University, 2019
WordPress VIP Certified
Development, Build, Test & Deployment, 2026
Open Source
GitHub Arctic Code Vault Contributor
LinkedInGitHub

Rajkiran founded SunReign Tech after seven years building software products used on more than two million websites — WordPress themes with a million active installations, React block libraries, and a headless commerce platform trusted by over a hundred thousand businesses.

He works across the whole stack: React and TypeScript on the front end, PHP 8 and REST architecture on the back, and a security practice unusual for a product engineer — remediating XSS, SQL injection and IDOR classes in production systems, each fix backed by regression coverage.

He has led engineering teams, set development standards, and mentored engineers through review and pairing. He is certified in the WordPress VIP build, test and deployment workflow, and uses AI-assisted development daily — including an MCP bridge he built to connect WordPress to Claude.

Capabilities

Languages & Core

  • JavaScript (ES6+)
  • TypeScript
  • PHP 8 (OOP/MVC)
  • HTML5
  • CSS3 / SCSS
  • SQL
  • Python

Front-End

  • React 19
  • Next.js (App Router)
  • Redux Toolkit
  • Context API
  • jQuery
  • Web Components (Stencil)
  • Tailwind CSS
  • Accessibility (WCAG)

WordPress

  • Custom Themes
  • Plugin Development
  • Gutenberg Blocks
  • Interactivity API
  • Full Site Editing
  • WooCommerce
  • WP REST API
  • WP-CLI
  • PHPCS / WPCS

Testing & Quality

  • Jest
  • React Testing Library
  • Playwright
  • PHPUnit
  • Regression testing
  • ESLint
  • Static analysis

Security

  • OWASP
  • XSS / CSRF prevention
  • SQL injection
  • IDOR & auth bypass
  • Sanitization & escaping
  • JWT auth flows
  • Vulnerability remediation

Infrastructure

  • Git & GitHub Actions
  • Docker
  • Vercel
  • WordPress VIP
  • Cloudflare CDN
  • Redis / Memcached
  • Sentry
  • Webpack

Contact

Tell us what you’re building.

Send us the shape of the problem — a rebuild, a migration, a security review, a platform that has outgrown itself. You’ll get a straight answer on scope, timeline and whether we’re the right team for it.

Email usConnect on LinkedIn
Based in
Pune, Maharashtra, India