Cork, Ireland —

Douglas
Pessoa.

Software Engineer. Seven years turning client problems into products that ship.

Douglas Pessoa smiling at a riverside viewpoint
Fig. 01 — PortraitIE / BR

01 — About

  • Cork
    Ireland

  • Rio de Janeiro
    Brazil

Senior Software Engineer with 7+ years architecting and shipping production-grade, multi-platform products across web, mobile, desktop, and backend. Specialized in real-time data systems, AI/LLM integration, and cloud cost optimization on AWS, building high-performance services in Node.js/TypeScript. Founder of an AI-powered mobile product, with hands-on expertise in LLM orchestration, prompt engineering, and tool-calling architectures via OpenRouter, including token-optimization techniques that cut AI costs without sacrificing quality. Proven record of owning the full software lifecycle, from system architecture and technical strategy through deployment, providing technical leadership across distributed teams and consistently driving measurable business impact.

Years in industry
7+
Teams & clients
14
Countries worked in
2

02 — Core skills

Languages
TypeScript · JavaScript · Go (Golang) · Python
Frontend
React · React Native · Next.js · Tauri · Micro Frontends · UI Component Libraries
Backend & APIs
Node.js · REST APIs · WebSockets · Real-Time Data Streaming
Cloud & DevOps
AWS (Timestream, infrastructure optimization) · Docker · CI/CD · Terraform
Databases
MongoDB · DynamoDB · PostgreSQL · MySQL
Architecture & Practices
System Architecture · Distributed Systems · Performance Optimization · Unit Testing · Agile · Technical Leadership · Mentoring
  • TypeScript
  • Go
  • Python
  • React
  • React Native
  • Next.js
  • Tauri
  • Node.js
  • WebSockets
  • AWS
  • Terraform
  • PostgreSQL
  • DynamoDB

03 — Projects

Octopus Volleyball logo

01

Octopus

Website and mobile app (iOS/Android)

In developmentWebiOSAndroidStripeApple / Google PaySSO
  • Building the entire product for the volleyball club, from website and iOS/Android apps to backend, owning the full lifecycle from product concept and UX to production deployment.

  • Integrated payments with Stripe, Google Pay, and Apple Pay for memberships and club purchases.

  • Implemented Google and Apple SSO for account creation and sign-in.

  • Building the app with Expo, React Native, TypeScript, and NativeWind for native performance, applying modular, type-safe architecture and reusable component design.

octopusvolleyball.club ↗
Mapyx app icon

02

Mapyx

AI-Powered Geography & Travel Intelligence App (iOS) · Founder · May 2026 – Present

Live on App StoreExpoReact NativeTypeScriptNativeWindOpenRouter
  • Founded and shipped Mapyx to the App Store: an AI-powered platform for exploring 200+ nations through curated geographical, historical, and cultural data, owning the full lifecycle from product concept and UX to backend, AI orchestration, and production deployment.

  • Designed a scalable data architecture to aggregate, normalize, and serve comprehensive datasets for 200+ countries and territories, solving data-consistency challenges at scale.

  • Engineered advanced LLM workflows via OpenRouter (prompt engineering, context management, and tool-calling) and built token-optimization algorithms that reduced AI operational costs while preserving output quality.

  • Built the app with Expo, React Native, TypeScript, and NativeWind for native performance, applying modular, type-safe architecture and reusable component design.

Download free on the App Store ↗

04 — Experience

Product teams in Ireland and Brazil, plus a long run of freelance work alongside them. Open any role for detail.

Jul 2026 — Present

Tigera

Software Engineer · Full time

Cork, Ireland · Hybrid2 mos

  • Building and maintaining user-facing features for Tigera’s cloud products, with a strong focus on usability, reliability, and a good user experience.

  • Working with React and TypeScript to develop and improve frontend functionality, while keeping the codebase maintainable and consistent.

  • Collaborating closely with Product, Design, Backend, and other Engineering teams to understand requirements and deliver features effectively.

  • Contributing to technical decisions, code reviews, testing, and improvements to frontend architecture and development practices.

  • Taking ownership of frontend tasks from planning through to delivery, while continuously learning from the team and contributing where I can.

ReactTypeScript
www.tigera.io ↗

May 2024 — Jul 2026

SensorComms

Senior Software Engineer · Full time

Cork, Ireland · Hybrid2 yrs 2 mos

  • Architected and built a real-time, multi-platform system from the ground up, spanning desktop, web, mobile, and backend, owning end-to-end technical strategy and system design.

  • Drove Go-based performance optimizations and a data-architecture redesign that reduced AWS costs by 15% and cut database utilization from 95% to 6%.

  • Designed a robust real-time data streaming pipeline to collect and visualize live temperature, voltage, and resistance readings through interactive charts, persisted in AWS Timestream.

  • Provide technical leadership and strategic direction, coordinating development and support teams to deliver high-quality, reliable systems.

  • Partnered with Reply (UK) to configure and optimize AWS infrastructure, enforcing performance, scalability, and security best practices.

  • Translate clients' operational challenges into scalable technical solutions, anticipating risks and shaping product direction across the full delivery lifecycle.

TypeScriptNext.jsReactNode.jsGoAWSAWS IoT CoreAWS DynamoDBAWS TimestreamTerraformTauriTesting LibraryHTMLTailwindShadcnBiomeRedis
sensorcomms.com ↗

Jun 2020 — Jan 2025

AFPUC

Full Stack Engineer · Freelancer

Rio de Janeiro, Brazil · Remote5 yrs 6 mos

  • Led the end-to-end redevelopment of the organization's web platform, introducing a user-friendly CMS that empowered non-technical teams to manage content independently.

  • Owned requirements discovery with stakeholders, documenting functional and non-functional requirements to align technical delivery with business goals.

  • Drove development and analysis initiatives that improved system reliability and overall platform performance.

  • Maintained and evolved the platform, delivering custom assets and continuous improvements while keeping the system stable and scalable.

TypeScriptJavaScriptPHPNext.jsjQueryNode.jsMongoDBGitWebpackJestTesting LibraryHTMLEmotionBootstrapCSSESLintPrettier
afpuc.com.br ↗

Apr 2022 — Oct 2024

Sensedia

Frontend Developer · Full-time

Campinas, São Paulo, Brazil · Remote2 yrs 8 mos

  • Modernized legacy software into a maintainable, component-driven architecture, delivering features independently from end to end.

  • Engineered and refined a shared UI component library in collaboration with frontend engineers and UI/UX designers, improving consistency and delivery speed.

  • Increased software resilience by implementing unit tests and strengthening coverage across core flows.

  • Mentored a technical writer into a fully independent frontend developer, supporting their growth within the team.

TypeScriptJavaScriptReactAngularNext.jsDockerGitBitbucketWebpackJestTesting LibraryHTMLStyled ComponentsCSSESLintPrettierAWSNginx
sensedia.com ↗

Oct 2020 — Jun 2022

Valora

Frontend Engineer · Full-time

Macaé, Brazil · Remote1 yr 9 mos

  • Built a platform and website from the ground up in close collaboration with the UI/UX design team.

  • Created an open-source UI component library, published on NPM and adopted across projects.

  • Contributed to frontend–backend alignment and supported the frontend team's day-to-day delivery.

TypeScriptJavaScriptReactNext.jsGitWebpackJestTesting LibraryCypressReduxHTMLStyled ComponentsCSSAnt DesignESLintAWSDockerNginxPrettierStorybookSwagger
valora.cc ↗

05 — Education

  • Jan 2020 – Jun 2023

    Bachelor's Degree, Computer Science

    Centro Universitário UniCarioca

  • 2016 – 2017

    Computer Technician, Information Technology

    Senac Brasil

06 — Languages

English
Fluent
Portuguese
Native / Bilingual
Spanish
Conversational