Adam Peña
I build high-performance UI infrastructure: accessible, battle-tested, and built to scale.
Experience
Founder, Full-Stack Engineer at Cindersoft
Feb 2025 — Present
- Built and launched SaaS platforms in React/Next.js, Node.js, and Python with shared UI libraries, CI/CD pipelines, and performance optimization baked in.
- Delivered AI-integrated features (real-time transcription, LLM evaluation tooling) for clients including OpenAI, Nvidia, and YC-backed startups.
Lead Full-Stack Engineer at Cash App
Oct 2022 — Feb 2025
- Architected and launched a cross-team marketing experimentation platform with a Node.js and React stack, improving conversion rates by 5% through faster A/B test deployment and real-time metrics via custom APIs.
- Led full stack performance initiatives, implementing server-side optimizations and front-end tuning to cut page load times by 70% and boost Lighthouse scores by 60+ points.
- Designed and deployed a headless CMS backed by custom API routes and edge functions, powering dynamic content and localization across 10+ regions without engineering support.
- Built and enforced CI pipelines for accessibility testing across marketing and product surfaces, achieving WCAG 2.1 compliance and integrating checks into the deployment process.
Senior Full-Stack Engineer at Plaid
Aug 2019 — Sep 2022
- Led development of a modular CMS with React, Node.js, and GraphQL, cutting content release time by 60% and enabling self-serve publishing across surfaces.
- Directed Plaid’s engineering apprenticeship program, overseeing mentorship, technical curriculum (React/Node), and logistics; achieved 100% conversion across 20+ apprentices.
- Led accessibility audits and full stack remediation across web surfaces, collaborating with backend teams to address semantic data issues and reduce support tickets by 75%.
- Built and maintained a shared UI library and supporting API interfaces adopted by multiple product teams, reducing UI bugs by 30% and enabling consistent design and faster rollouts.
Software Engineer at Visibly
Sep 2017 — Jul 2019
- Improved onboarding workflows and signup flows, increasing user retention by 25% and boosting first-time purchase conversion by 4%.
- Developed rich, interactive UI components for a proprietary online vision test, contributing to a smoother and more accurate test-taking experience.
Front-End Engineer at Arrive
Mar 2016 — Sep 2017
- Redesigned and optimized the core parking widget, increasing performance by 40% and improving booking funnel completion rates.
- Built and shipped a new B2B platform for enterprise partners, reducing client expense report processing time by 35%.
Currently building under Cindersoft®
AIO Ready™
AIO Ready is a tool that tests how AI agents like GPT or Claude interpret and attempt to interact with modern websites. It helps uncover UX blockers that can break automation, AI search, or LLM-based flows.
Visit aioready.com