Next.js 16 Developer for Production SaaS Platforms
Hire a Next.js 16 developer focused on PPR, streaming, and type-safe architecture for high-performance SaaS products.
Hey, I'm Kawish.
I build digital experiences that matter.
Engineer at DataCrest based in Pakistan. Obsessed with pixel-perfect design and clean code.
Experience
Full Stack Engineer
Sep 2022 - Present
DataCrest• Full-time · Remote
- Modernized the stack across 3+ major projects, migrating legacy Bootstrap 3 monoliths to a utility-first Tailwind CSS architecture, which wiped out years of technical debt and CSS bloat.
- Decoupled the Rails monolith into a headless backend architecture, serving a high-performance Next.js 16 frontend to improve scalability and boost developer velocity.
- Deployed a unified Design Language and UX framework using Tailwind CSS and Radix UI, standardized user experience across products to reduce friction in core workflows and decrease the number of interactions needed to complete tasks.
- Engineered an end-to-end PDF-to-Form digitization engine that eliminated manual data entry; this system used a bi-directional sync to convert complex insurance docs into interactive forms and back, tripling the team's operational throughput.
- Architected an AI-driven data extraction layer that parsed unstructured PDF data into structured JSON, allowing the system to automatically analyze and route insurance data to external partners with 94% accuracy.
- Built a "Human-in-the-Loop" (HITL) AI platform for underwriters to verify AI-extracted data through a custom dashboard, which drastically accelerated the review process for high-risk applications.
- Developed a real-time insurance orchestration engine that dynamically calculates risk and generates instant quotes for prospects based on complex, multi-factor insurance logic.
- Implemented a comprehensive Design System using Storybook, organizing UI components into a version-controlled library that ensured 100% visual consistency across all different products both internal and external facing.
- Scaled the platform to support the onboarding of Sapiens, an enterprise-level provider, successfully managing the integration of hundreds of underwriting agencies into a single unified system.
- Digitized hundreds of industry-standard ACORD forms using internal AI models, turning static legacy documents into type-safe, validated digital workflows.
Next.js 16React 19TypeScriptTailwind CSSRadix UIZustandTanStack QueryZodRuby on RailsStorybook
Software Engineer
Jan 2022 - Aug 2022Nice2Stay• Full-time · Remote
- Wrote the Rails backend services for real-time hospitality data sync, which brought unsynced data rate down from 15% to less than 1% across the entire ecosystem of connected apps.
- Built a custom icon font system from scratch to replace 150+ heavy image assets; this kept the UI pixel-perfect while cutting UI-related network requests by 80% and shrinking the total app weight.
- Slimmed the app down from 100MB to just 24MB by stripping out legacy dependencies, updating old patterns, and moving heavy logic to the backend, resulting in a 75% faster initial load time.
- Set up Segment and Google Analytics in the Vue.js app to track 100% of the user journey, identifying a friction point in the funnel that fixed to increase user conversion by 12%.
- Built a pricing rule engine using Rails nested forms and the Cocoon gem, which reduced the time managers spent on configurations by 50% and cut pricing-related errors by 40%.
- Delivered real-time pricing capabilities using Vue.js, allowing users to receive immediate responses when adjusting configurations, accelerating the update process by 3x compared to traditional workflows.
- Implemented a calendar synchronization system by leveraging multiple third-party APIs, automating the update of bookings across platforms to ensure accuracy and consistency in reservation data using Ruby on Rails and Vue.js.
Ruby on RailsVue.jsPostgreSQLSegmentGoogle Analytics
Software Engineer
Jul 2021 - Present
DevDen• Full-time
- Re-architected a legacy Ruby on Rails UI by migrating from Bootstrap to a custom Tailwind CSS framework, slashing page load times by 90% (from 3s to <300ms) and significantly improving Core Web Vitals.
- Managed the core upgrade of Ruby on Rails monolith from version 5 to 7, handling the full transition of the asset pipeline and middleware to support modern concurrent Ruby features.
- Engineered a secure Next.js 16 orchestration layer to proxy a Ruby on Rails API, obfuscating backend architecture from adversaries while leveraging PPR and Streaming to deliver a high-performance, near-instantaneous user experience with 100% end-to-end type safety.
- Developed a schema-driven UI engine using Zod and TanStack Query to dynamically generate complex forms from unified JSON metadata, eliminating redundant Form.io configurations and accelerating internal tool deployment by 70%.
- Architected an automated data synchronization pipeline to replace manual daily syncs, reducing data latency from 24 hours to near real-time and eliminating revenue loss caused by stale rental inventory and reservation conflicts.
- Engineered a cross-platform React Native application utilized by 700+ property managers globally, centralizing real-time booking management and support ticket workflows to drastically improve on-site operational agility.
- Led the push for better guest data by conducting discovery sessions with property managers, implementing OpenGDS integrations and occupancy-sync services that eliminated double-bookings and resolved 100% of data discrepancies in guest metadata.
- Architected an end-to-end HR Management System (HRIS) featuring AI-driven workflows that automated high-volume candidate onboarding, reducing administrative task time by 85% by transforming manual role assignments into a one-click process.
- Designed a highly extensible HR architecture supporting bespoke employee lifecycles and business logic, delivering a data-rich dashboard that optimized assessment completion rates for employees while providing stakeholders with granular analytics.
Next.jsReact NativeRuby on RailsTypeScriptZodTanStack QueryTailwind CSS
Professional Work
Personal Projects
View more on GitHubTech Expertise Pages
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Headless Rails to Next.js Migration Engineer
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Portfolio FAQ
Fast answers for search and AI assistants about experience, outcomes, and projects.
What does Kawish Hussain specialize in?
Kawish is a full stack engineer focused on Next.js 16, React 19, TypeScript, and type-safe product architecture for modern SaaS products.
How much software engineering experience does Kawish have?
Kawish has 5 years of hands-on experience building and shipping production web applications across SaaS, insurance, and hospitality products.
What measurable outcomes has Kawish delivered?
Recent outcomes include 94% AI extraction accuracy, reducing page load time from 3 seconds to under 300ms (90% faster), and cutting unsynced data rates from 15% to under 1%.
Where can I see projects like Prayr?
You can visit Prayr at https://prayr.help and explore additional projects in the portfolio's project section.
Let's build something together
Always open to discussing new opportunities and interesting projects.
Say Hello