// 01 / IndexSenior Software Engineer
// Based inCuritiba, Brazil --:--:-- BRT

Engineering high-performance web products for millions of users.

I'm Guilherme Illescas — a senior full-stack engineer who cares deeply about the small details in interfaces. Right now I'm building AI sales tools at AwSales. Before that, I led product engineering at Conquer (1M+ certificates issued) and co-founded Amank (acquired in 2024).

See selected workLet's talk
5M+
users reached across live products around the world.
27K+
active customers supported on highly reliable platforms.
6yr
building reliable software, from startups to larger companies.
// 02 — ABOUT
The engineer

A craftsman, not a ticket closer.

I believe great software is invisible — until you compare it with the alternatives. The interfaces I build aim for exactly that: fast, thoughtful, accessible, and with a clear point of view.

Six years into my career, I've designed and launched applications used by 5M+ people worldwide. I've led teams, built design systems, improved old codebases, founded a SaaS that was acquired in 2024, and learned that the best engineers care just as much about performance, writing, and how the product feels to use.

I'm currently a Senior Software Engineer at AwSales, where I help build AI agents that handle sales on their own. When I'm not coding, I'm usually teaching, reading about systems thinking, or planning my next side project.

~/guilherme.json
role
Senior Software Engineer
based
Curitiba, BR
company
AwSales — Full-time
local time
--:--:-- BRT
status
● Open to full-time roles
timezone
UTC−3 (BRT)
Currently working with
  • React 19
  • Next.js 15
  • TypeScript
  • React Query
  • Nuxt 3
  • Prisma
  • Tailwind v4
  • Node.js
  • Stripe
// 03 — EXPERIENCE
Career, as a changelog

Releases v1.0 → v7.0.

Each role is a major version. Each line is a real change I delivered — features, refactors, leadership. No filler.

Download CV
08releases shipped
  1. v7.0.0LATESTguilherme/careerawsales
    Jul 2024 → present2y · current
    RoleSenior Software EngineerFull-time · Remote

    An AI-powered sales platform — WhatsApp outreach, lead recovery, campaigns, AI assistants, and integrations like Hotmart and Stripe. I work across both the customer platform and the internal back-office, owning features from start to finish.

    Was one of the engineers who built the core of the platform that's live today — shaping key technical decisions: changing flows, adjusting the data structure, and proposing solutions to reach the final result
    Built and maintain the Stripe billing integration — subscriptions, webhooks and the full subscription lifecycle
    Built the internal back-office app (Nuxt + Node) with two other engineers — the tool the operations team uses every day
    Handle customer bugs end to end — taking issues straight from the client and fixing them across the whole stack, from database to frontend
    Built the whole component library from scratch with React, Vite and Storybook, tested with Jest and Playwright — reusable components that keep the UI consistent
    Ship customer-facing features — I design, build and refactor important flows, working closely with Product and Design
    Help drive product discovery — scoping features, simplifying user journeys and keeping the roadmap aligned with the business
    • Next.js
    • TypeScript
    • React
    • Vite
    • React Query
    • Node.js
    • Nuxt
    • Prisma
    • GraphQL
    • Stripe
    • WhatsApp API
    • Tailwind
    • Storybook
    • Jest
    • Playwright
    • GCP
    • Docker
    • GitHub Actions
    • Figma
  2. v6.0.0CURRENTguilherme/careerviralifySide project
    Aug 2025 → present11mo · side project
    RoleCo-founder & Software EngineerFounder · Side project

    An AI SaaS that turns viral content into sales — daily AI analyses and AI-generated scripts. I'm the sole owner of product and engineering; my co-founder runs business and content. A part-time side venture, alongside my full-time role at AwSales.

    Built the product end to end — frontend, backend, data modeling (MongoDB) and deployment (Vercel) — as the only engineer and owner of every technical and product decision
    Created the AI script-generation engine — it analyzes the scripts of videos that already went viral and generates new scripts tailored to each user's niche, integrating the OpenAI and Anthropic (Claude) APIs
    Implemented the entire Stripe billing layer — recurring subscriptions, webhooks and subscription lifecycle
    Led a product pivot, from a library of viral scripts to an AI script generator, driven by real user behavior
    Traction: 180+ signups and 40 active paying subscribers (~22% signup-to-paid conversion); the subscriber base nearly doubled (19 → 40) in the first 6 weeks after launch
    • Next.js
    • React
    • TypeScript
    • Node.js
    • MongoDB
    • Mongoose
    • Prisma
    • NextAuth
    • Stripe
    • OpenAI
    • Claude
    • Puppeteer
    • Zod
    • React Hook Form
    • Zustand
    • Tailwind
    • Radix UI
    • Framer Motion
    • Three.js
    • Resend
    • Vercel
  3. v5.0.0PART-TIMEguilherme/careerprevidenciarista
    Oct 2023 → Sep 20252y · full-time → part-time
    RoleSenior Software EngineerFull-time · Remote
    Went part-time in Jul 2024 when I joined AwSales (full-time) — kept the platform stable through the transition.

    A business-critical SaaS platform serving 27K+ active customers — lawyers running pension calculations and legal petitions. I worked across the main product and the website, focused on performance, SEO and reliability.

    Improved website performance through targeted refactors and best practices (Core Web Vitals & Lighthouse)
    Improved SEO with structured data, Google Analytics and Google Tag Manager — and tracked the results
    Delivered features across the product with Next.js, TypeScript, Tailwind CSS and React Hooks
    Set up and maintained the CI/CD pipeline for faster, more reliable releases
    Reduced a lot of code complexity through refactors — an easier codebase and a faster team
    Wrote unit and end-to-end tests with Jest and Playwright to keep quality high
    • Next.js
    • React
    • TypeScript
    • Tailwind
    • React Hooks
    • Jest
    • Playwright
    • GA
    • GTM
    • SEO
  4. v4.1.0guilherme/careerescola-conquer
    Oct 2022 → Oct 20231y 1mo · promotion
    RoleSenior Software EngineerFull-time · Hybrid

    Promoted to Senior. Conquer Plus is an education platform that reached 5M+ users worldwide and issued 1M+ certificates — still live today. I led the code architecture and the frontend, working across the stack with a strong frontend focus.

    Was the frontend reference for the team — led the code architecture and frontend, making the technical decisions that shaped the platform that's live today
    Led a survey product end to end, frontend and backend — a dynamic survey used from collecting feedback to measuring a student's level
    Built and maintained the internal Design System in Figma and code, with Storybook, so teams across the company could reuse components
    Led the implementation of micro-frontends with Single SPA — each domain deploying on its own
    Joined the product committee and mentored junior and mid-level engineers on both code and product
    Created the projects for the frontend and Node courses and helped build the React course; shipped features (Next.js, TypeScript, Styled-Components) and tuned performance via Lighthouse
    • Next.js
    • TypeScript
    • Styled Components
    • React Hooks
    • Single SPA
    • Storybook
    • Figma
    • Leadership
  5. v4.0.0guilherme/careerescola-conquer
    Sep 2021 → Oct 20221y 2mo · full-time
    RoleSoftware EngineerFull-time · Hybrid

    Joined Conquer Plus as a mid-level engineer and was promoted to Senior in Oct 2022. A hands-on phase — building the product and growing with the team.

    Built features end to end as a full-stack developer, across frontend and backend
    Designed and implemented new features that improved the platform and the user experience
    Fixed bugs and improved the software's reliability and performance
    Supported teammates day to day and created content for the programming courses, turning technical topics into clear lessons
    • React
    • TypeScript
    • Node.js
    • Styled Components
    • REST APIs
  6. v3.0.0guilherme/careeramank → bhubSide project
    Jun 2021 → May 20232y · founder
    RoleCo-founder & Senior Software EngineerFounder · Side project

    Co-founded Amank — a SaaS platform that helped companies centralize, control and reduce their software costs. I owned the front-end and built it from the ground up while helping run the company day to day. Acquired by BHUB in 2024.

    Co-founded the company and built the product's front-end from zero — a modern stack for usability, performance and scalability
    Helped run the company beyond code — product planning, architecture and end-to-end development, shaping features and UX from the start
    Operated in real founder mode — balancing speed, customer value and technical tradeoffs in an early-stage environment, wearing many hats
    Outcome: Amank stood out in the market and was acquired by BHUB in 2024
    • React
    • Next.js
    • TypeScript
    • Styled Components
    • REST APIs
    • Founding team
  7. v2.0.0guilherme/careerchamer-tech
    Feb 2021 → Sep 20218mo · full-time
    RoleSoftware EngineerFull-time · On-site

    Drove feature development across e-commerce platforms and data-driven dashboards in a small, fast-moving team — with REST APIs for seamless database integration.

    Built and shipped key features across platforms with React and TypeScript, improving interaction and functionality
    Spearheaded e-commerce platforms and data-driven dashboards that improved operations and decision-making
    Implemented advanced SEO — improved organic search rankings, traffic and user acquisition
    Optimized application performance — reduced load times and improved responsiveness
    • React
    • TypeScript
    • REST APIs
    • E-commerce
    • SEO
  8. v1.0.0guilherme/careerwebtrip
    Jan 2020 → Nov 202011mo · full-time
    RoleJunior Software EngineerFull-time · On-site

    Where I got my start — a versatile role spanning full-stack web work, server management, telephony and IT support in a small team.

    Automated 6+ internal reporting flows with Google Apps Script — manual data entry down 70%, phone calls down 12%
    Designed and implemented 10+ process improvements, reducing turnaround time
    Improved the company's websites (HTML, CSS, JavaScript) and managed Suite CRM for the sales team
    Maintained servers and telephony (IVR + extensions), keeping operations running
    • HTML
    • CSS
    • JavaScript
    • Apps Script
    • Suite CRM
    • DevOps
// 04 — SELECTED WORK
Selected work

Things I've shipped.

// 05 — PROCESS
Behind the build

How this site was made.

Designed from start to finish with a documented system. Every token, motion curve, and wording choice is intentional — and openly published.

v1launched Jan'26
01 / Concept

Career as a changelog.

Each role becomes a semantic version. Bullets become diff lines. Companies become git tags. This metaphor runs through the whole experience section.

02 / System

Tokens before pixels.

Palette, type scale, 8pt spacing and motion easing locked in CSS variables before a single layout was drawn. One source of truth — globals.css.

03 / Motion

Movement with purpose.

Reactive grid, headline cascades, magnetic CTAs, scroll-linked timeline. Every animation guides attention or rewards exploration — never decoration.

04 / Voice

Show, don't tell.

Real numbers (5M+ users, 27K+ customers) instead of adjectives. Short, direct CTAs. Code-comment markers as section dividers. No buzzwords.

Read the full design systemView source on GitHub
// 06 — CONTACT

Got something worth building?

oi@guilhermeillescas.devSchedule a call