Senior Software Engineer

Who we are

At Fluxon, we believe that how you build matters as much as what you build. We help businesses navigate their most important technology decisions with confidence, and take responsibility for seeing them through. Founded by ex-Googlers and startup veterans, we’re proud to partner with teams behind some of the most ambitious products, including Google, OpenAI, Anthropic, Walmart and Stripe.

Our work spans strategy, design, and engineering — often in complex, AI-driven environments — where clarity, speed and quality are the standard. We use AI intentionally, applying it only where it adds real value and expands what’s possible. Care shapes everything we do.

Inside Fluxon, you’ll find a global, remote-first team of experienced builders, who are curious, kind and serious about their craft. We’re building a place where people can take ownership, solve problems that matter and do work they’re proud to stand behind. If you want to do your best work alongside people who care as much as you do, you’ll feel at home here.

Note: This position is fully remote and open to candidates based anywhere in Portugal.

About the role

As a Senior Software Engineer at Fluxon, you'll have the opportunity to bring products to market while learning, contributing, and growing with our team.

You'll be responsible for:

Driving end-to-end implementations all the way to the user, collaborating with your team to build and iterate in a dynamic environment

Engaging directly with clients to understand business goals, give demos, and debug production issues

Informing product requirements, identifying appropriate technical designs in partnership with our Product and Design teams

Proactively communicating progress and challenges in your work and seeking help when you need it

Performing code reviews and cross-feature validations

Providing mentorship in your areas of expertise

You'll work with a diversity of technologies, including:

Languages

TypeScript/JavaScript, Java, .Net, Python, Golang, Rust, Ruby on Rails, Kotlin, Swift

Frameworks

Next.js, React, Angular, Spring, Expo, FastAPI, Django, SwiftUI

Cloud Service Providers

Google Cloud Platform, Amazon Web Services, Microsoft Azure

Cloud Services

Compute Engine, AWS Amplify, Fargate, Cloud Run

Apache Kafka, SQS, GCP CMS

S3, GCS

Technologies

AI/ML, LLMs, Crypto, SPA, Mobile apps, Architecture redesign

Google Gemini, OpenAI ChatGPT, Vertex AI, Anthropic Claude, Huggingface

Databases

Firestore(Firebase), PostgreSQL, MariaDB, BigQuery, Supabase

Redis, Memcache

Qualifications

5+ years of industry experience in software development

Experienced with the full product lifecycle, including CI/CD, testing, release management, deployment, monitoring and incident response

Fluent in software design patterns, scalable system architectures, tooling, fundamentals of data structures and algorithms

What we offer

Remote-first, flexible work with a budget to set up a work space that works for you

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