FastAPI Jobs in Portugal.
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Senior ML-Engineer
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Highlights:
Role: Senior ML-Engineer
Location: Portugal, Remote
Language: Russian-speaking team; Strong English required (B2)
About Us
Fundraise Up is a modern fundraising platform built to make donating to nonprofits as fast and convenient as possible. We continuously innovate to reduce page load times, boost conversion rates, and support a wide range of payment methods. Each month, people around the world contribute tens of millions of dollars through our platform.
The world’s leading nonprofit organizations trust Fundraise Up. UNICEF, the most prominent UN charity, uses our platform for 100% of its online fundraising. So does the American Heart Association, the Alzheimer’s Association, and many others. We’re proud to maintain a 4.9 out of 5 rating on leading review platforms.
We serve the enterprise segment, with a primary client base in the US, Canada, UK, and Australia.
The Team
Our product development team is currently at 150+ and growing. Team members are located across Spain, Serbia, Poland, Portugal, Turkey, Cyprus, Georgia and Armenia. We primarily communicate in Russian.
We’re a tight-knit, high-impact team where every task matters. It’s a dynamic, collaborative environment where smart, curious engineers support one another, share knowledge, and strive for excellence. We encourage open dialogue and host bi-weekly engineering meetups to explore technical topics and showcase team insights.
About the Role
We're looking for an ML Engineer with 5+ years of production experience to strengthen our ML team. We operate as an internal service and centre of excellence for 10+ product teams at Fundraise Up. This means you won't be tied to a single feature: one day you might be optimising donation amounts and upsell offers, and the next you could be building a smart assistant for the admin panel or working on transaction classification.
We actively use not only classical ML, but also RL, and we're expanding our LLM-based solutions — prompt engineering and pipeline design with LLM APIs (OpenAI and equivalents). That's why we're looking for someone with a broad mindset who isn't afraid to experiment and can choose the most effective approach for each task.
The project's main audience and business team are based in the US. Although the product development team is Russian-speaking, you may occasionally need to write in English.
What You’ll Do
- Develop and deploy ML solutions across different business areas using tabular data (uplift models, recommender systems). We are also actively developing projects that will involve e-commerce mechanics.
- Select the most appropriate ML/LLM approaches or propose alternative solutions.
- Build end-to-end ML solutions: data preparation, training, API development, and monitoring.
- Design prompts and LLM API-based pipelines for specific product tasks: classification, content generation, and response quality evaluation.
Requirements
- 5+ years of ML/DS experience solving real product problems
- Strong expertise in ML and mathematical statistics: solid knowledge of classical algorithms (especially gradient boosting); NLP knowledge is a plus
- Metrics-driven mindset: ability to connect ML metrics (ROC-AUC, F1, RMSE) with business metrics (CR, LTV)
- Strong engineering culture: confident in Python with a product-oriented approach to development; we value clean code, knowledge of design patterns, and solid engineering practices
- Data skills: advanced SQL; ability to independently and efficiently build complex datasets in ClickHouse and work with MongoDB
- MLOps understanding: hands-on experience with experiment tracking tools and understanding of production workflows (Docker, Git, CI/CD)
- Autonomy: ability to break down problems, choose the right tech stack (or justify a non-ML solution), and deliver to production
Our Tech Stack
Core: Python (uv, ruff), FastAPI, Pydantic, Docker
Models: CatBoost, Uplift Modeling (CausalML), OpenAI (RAG, Prompt-Engineering)
Data: ClickHouse, MongoDB, pandas, Polars, Redis
MLOps: MLflow, Airflow
Monitoring: Grafana, Sentry
Why work with us
- A strong, collaborative product team that owns what it builds
- Clear product vision and access to real customer feedback from global nonprofit leaders
- Flat structure: no politics, just great work with great people
- Transparent company culture-we share how we’re growing, where revenue comes from, and what’s next
- Long-term focus: we offer equity options and value sustained, meaningful contribution
Benefits
- Private medical insurance for the employee and their family
- 22 paid vacation days per year
- Up to 14 paid public holidays per year
- 5 company-paid sick leave days
- English learning courses.
- Relevant professional education.
- Gym or swimming pool.
- Home Office Setup Assistance: the company offers assistance with purchasing furniture (office chair, office desk, monitor) and other items to create a comfortable workspace.
- Co-working.
- Remote working.
- €50 monthly allowance to cover internet and mobile phone expenses
**Please note: All official correspondence from Fundraise Up will exclusively originate from the @fundraiseup.com domain. Exercise caution and ensure the authenticity of emails claiming to be from our company.
We are an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. We do not discriminate on the basis of race, color, religion, gender, sexual orientation, gender identity or expression, age, national origin, disability, or any other characteristic protected by applicable law in the countries where we operate.
Ready to apply?
Apply to Fundraise Up
Senior ML-Engineer, Finance
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Highlights:
Role: Senior ML-Engineer, Finance
Location: Portugal, Remote
Language: Strong English required (C1)
About Us
Fundraise Up is a modern fundraising platform built to make donating to nonprofits as fast and convenient as possible. We continuously innovate to reduce page load times, boost conversion rates, and support a wide range of payment methods. Each month, people around the world contribute tens of millions of dollars through our platform.
The world’s leading nonprofit organizations trust Fundraise Up. UNICEF, the most prominent UN charity, uses our platform for 100% of its online fundraising. So does the American Heart Association, the Alzheimer’s Association, and many others. We’re proud to maintain a 4.9 out of 5 rating on leading review platforms.
We serve the enterprise segment, with a primary client base in the US, Canada, UK, and Australia.
The Team
Our product development team is currently at 150+ and growing. Team members are located across Spain, Serbia, Poland, Portugal, Turkey, Cyprus, Georgia and Armenia. We primarily communicate in Russian.
We’re a tight-knit, high-impact team where every task matters. It’s a dynamic, collaborative environment where smart, curious engineers support one another, share knowledge, and strive for excellence. We encourage open dialogue and host bi-weekly engineering meetups to explore technical topics and showcase team insights.
About the Role
We're looking for an ML Engineer with 5+ years of production experience to own a high-impact client intelligence initiative. Following a successful proof-of-concept with an external consultant, we are bringing this project fully in-house. The ultimate goal is to generate a comprehensive, enriched list of all potential clients globally — understanding their product requirements, industry verticals, and overall revenue potential — and deploy a scoring model that feeds directly into our sales pipeline.
This is an end-to-end ownership role. You will build from the ground up: data collection, enrichment, modeling, and production deployment. The project is co-managed by company executives and has a high strategic value.
What You’ll Do
- Build a market intelligence data-base via collecting different types of data (scraping, enrichment), fixing data pipeline and creating an ML model for scoring and analysis of the raw data.
- Design and operate scrapers to extract key signals from nonprofit websites, including products used, payment tools, and industry vertical indicators.
- Develop critical filters such as an "Is this website for fundraising?" binary classifier, alongside other features that distinguish high-potential prospects.
- Source and integrate financial data from international nonprofit registries, as well as third-party signals from SimilarWeb and Facebook.
- Store and structure the enriched dataset in our internal database, making it accessible and useful across the broader team for research and analysis.
- Work closely with the sales team to understand their qualification criteria. Analyze disqualified accounts in Salesforce to identify common exclusion patterns and refine scoring accordingly.
- Deploy the scoring model and own the process of integrating outputs into Salesforce in a clean, maintainable way.
- Build a scraper to monitor existing clients' websites, tracking whether Fundraise Up tools are correctly implemented across their properties.
Challenges You'll Navigate
- At the scale of ~1 million domains, expect domain duplicates, inconsistent data, and significant noise. You'll need to develop robust, cost-efficient filtering pipelines.
- A single model won't cover everything — you'll likely build several targeted sub-models tailored to specific verticals and geographies as the project matures.
- All of this needs to be accomplished without incurring high infrastructure or data costs. Pragmatic, scrappy solutions are valued here.
Requirements
- 5+ years of ML/DS experience solving real product problems
- Strong expertise in ML and mathematical statistics: solid knowledge of classical algorithms (especially gradient boosting) and understanding of modern NLP/LLM approaches
- Proven experience with large-scale web scraping and data pipeline construction
- Metrics-driven mindset: ability to connect ML metrics (ROC-AUC, F1, RMSE) with business metrics (conversion rate, LTV)
- Strong engineering culture: confident in Python with a product-oriented approach; we value clean code, knowledge of design patterns, and solid engineering practices
- Advanced SQL; ability to independently build complex datasets in ClickHouse and work with MongoDB
- MLOps understanding: hands-on experience with experiment tracking and production workflows (Docker, Git, CI/CD)
- Autonomy: ability to break down ambiguous problems, choose the right tech stack, and deliver to production
Our Tech Stack
Core: Python (uv, ruff), FastAPI, Pydantic, Docker
Models: CatBoost, Uplift Modeling (CausalML), OpenAI (RAG, Prompt-Engineering)
Data: ClickHouse, MongoDB, pandas, Polars, Redis
MLOps: MLflow, Airflow
Monitoring: Grafana, Sentry
Infra: linux server admin, distributed computation
Bonus points
- Curiosity and a hypothesis-driven mindset
- Ability to communicate complex analytical concepts to non-technical audiences
- Detail-oriented with a strong sense of ownership
- Comfort working in fast-paced, data-rich environments
Why work with us
- A strong, collaborative product team that owns what it builds
- Clear product vision and access to real customer feedback from global nonprofit leaders
- Flat structure: no politics, just great work with great people
- Transparent company culture-we share how we’re growing, where revenue comes from, and what’s next
- Long-term focus: we offer equity options and value sustained, meaningful contribution
Benefits
- Private medical insurance for the employee and their family
- 22 paid vacation days per year
- Up to 14 paid public holidays per year
- 5 company-paid sick leave days
- English learning courses.
- Relevant professional education.
- Gym or swimming pool.
- Home Office Setup Assistance: the company offers assistance with purchasing furniture (office chair, office desk, monitor) and other items to create a comfortable workspace.
- Co-working.
- Remote working.
- €50 monthly allowance to cover internet and mobile phone expenses
**Please note: All official correspondence from Fundraise Up will exclusively originate from the @fundraiseup.com domain. Exercise caution and ensure the authenticity of emails claiming to be from our company.
We are an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. We do not discriminate on the basis of race, color, religion, gender, sexual orientation, gender identity or expression, age, national origin, disability, or any other characteristic protected by applicable law in the countries where we operate.
Ready to apply?
Apply to Fundraise Up
Senior Software Engineer, Geospatial Data
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The climate crisis is the defining challenge of our time—but it’s also the greatest opportunity for innovation, and a challenge we’re proud to take on. At Overstory, we’re harnessing cutting-edge technology to enable a resilient electrical grid that keeps communities thriving as our world changes.
The grid is the backbone of life as we know it. It powers hospitals, keeps food fresh, and ensures communities stay connected. But extreme weather, aging infrastructure, and growing wildfire risks are putting this critical system under pressure. All of this combined makes the electric utility industry the greatest opportunity for tackling climate change.
One of the leading causes of catastrophic wildfires and power outages? Trees and brush coming into contact with power lines.
That’s where we help. At Overstory, we use AI and advanced satellite imagery to pinpoint and prioritize vegetation risks before they materialize. By giving utilities critical analysis on those risks, we’re helping prevent outages, reduce wildfire risks, and accelerate the transition to a safer, more resilient grid.
Our team spans the Americas and Europe, and we work with utility partners across the Americas and beyond. We’re outdoor enthusiasts, musicians, artists, athletes, parents, and adventurers. What unites us is a passion for solving complex problems, a commitment to climate action, and the belief that technology should be a force for good.
Join us to help us build a more resilient world together.
Role & Team
As a Senior Engineer, you will have a direct impact on the development of core geospatial products and internal data-processing and annotation tools at Overstory.
Your breadth of skills will allow you to set a technical vision for the development of the web applications, ETL pipelines, and backend services owned by these teams.
You’ll partner with product managers, external resources, and your team members to execute this vision.
Time zone requirement: Europe (GMT/WET, CET, EET) and North America (NST, AST, EST, CST, MST, PST)
What You’ll Do
- Explore best practices to combine coding agents with software craftsmanship and teach other engineers these practices
- Optimize the orchestration of several object detection and image alignment models
- Design and maintain robust data and feature pipelines for millions of geospatial entities
- Contribute to the technical vision for the development of our internal annotation and QA web applications
- Work closely with your Product Manager to discover and propose new products to solve use cases such as anticipating the impact of an outage at a particular locatio
Skills & Experience
- 5+ years of experience as a senior software engineer
- Skilled in designing ETL pipelines with near-real-time orchestration, in Python.
- Strong background building and maintaining scalable web-applications with React, FastAPI, PostgreSQL
- Experience with XP practices such as TDD or trunk based development. The team would be new to these practices
- Strong communication skills and ability to explain complex technical concepts to various audience
Nice To Have
- Experience with the Geospatial ecosystem such as PostGIS, Geopandas or Deck.GL
- Experience with Dagster, Airflow or similar orchestration frameworks
- Experience with building web-applications tailored for repeatable human or agentic workflows
- Experience working in B2B, in particular with electrical utilities
Note: We believe that all people are capable of great things. We encourage you to apply even if you do not meet all of the requirements that are listed within this job description.
What We Offer
- Competitive, location-specific compensation and benefits
- Flexible, autonomous and collaborative working environment rooted in trust - we build our work days around our lives, not the other way around
- Home office stipend, coworking and ongoing education budgets
- A company culture that genuinely embodies each of our core values
- To be part of truly mission-driven work that reduces wildfires, protects earth’s natural resources and helps solve our climate crisis
About Our Team
We are a group of 100 people from all over the world. Fifteen nationalities are represented in our team and at last count we speak fourteen languages: English, Dutch, French, Spanish, German, Italian, Portuguese, Russian, Luxembourgish, Lithuanian, Bulgarian, Cantonese, Estonian, and Danish.
We work remotely from eleven countries and are looking for candidates that are living and working in one of them: United States, the Netherlands, United Kingdom, Ireland, Estonia, Portugal, France, Sweden, Switzerland, Denmark and Canada. We gather once a year in-person for our unforgettable team gathering event. We also offer the option to occasionally meet up for in-person collaboration.
Diversity & Inclusion
The climate crisis is a human crisis that requires diverse perspectives to solve.
We place enormous value on diversity and believe that the best ideas emerge when people with different backgrounds and experience work together. We remain committed to scaling a team that reflects the communities we serve, and strive to uphold equitable and inclusive practices across every aspect of our business. We are responsible for creating and maintaining a culture where everyone - regardless of background - has a voice in building a sustainable future.
Our Values
Tackling the climate crisis is our greatest mission.
We act with urgency.
Our curiosity fuels our growth.
We recognize that change is constant, and we find joy and power in exploration.
We’re rooted in diversity.
Just as ecosystems need biodiversity to thrive, our resiliency comes from our differences.
We care for each other.
We love the power of machines but we nurture each other as humans.
Trust is fundamental.
We assume the best in everyone, and we share ideas openly so that we have a positive impact.
_________________________________
Use of AI in Our Hiring Process
We sometimes use AI tools to support parts of our hiring process, such as helping us manage applications more efficiently or ensuring job descriptions are clear and inclusive. All hiring decisions are always made by people, not machines. Any data processed by AI is handled securely in line with GDPR and our Privacy Notice.
Ready to apply?
Apply to Overstory
Staff Software Engineer
Share this job
The climate crisis is the defining challenge of our time—but it’s also the greatest opportunity for innovation, and a challenge we’re proud to take on. At Overstory, we’re harnessing cutting-edge technology to enable a resilient electrical grid that keeps communities thriving as our world changes.
The grid is the backbone of life as we know it. It powers hospitals, keeps food fresh, and ensures communities stay connected. But extreme weather, aging infrastructure, and growing wildfire risks are putting this critical system under pressure. All of this combined makes the electric utility industry the greatest opportunity for tackling climate change.
One of the leading causes of catastrophic wildfires and power outages? Trees and brush coming into contact with power lines.
That’s where we help. At Overstory, we use AI and advanced satellite imagery to pinpoint and prioritize vegetation risks before they materialize. By giving utilities critical analysis on those risks, we’re helping prevent outages, reduce wildfire risks, and accelerate the transition to a safer, more resilient grid.
Our team spans the Americas and Europe, and we work with utility partners across the Americas and beyond. We’re outdoor enthusiasts, musicians, artists, athletes, parents, and adventurers. What unites us is a passion for solving complex problems, a commitment to climate action, and the belief that technology should be a force for good.
Join us to help us build a more resilient world together.
Role & Team
As a Staff Engineer, you will work across multiple teams to evolve a suite of web and internal tools that enable utility companies to more effectively manage risks associated with climate change and wildfires.
We are seeking improvement in the following areas:
- Performance & Scalability: ensure that our product can handle 3x YoY growth
- Accelerate time to value of new product capabilities
- Reduce the amount of manual work required to ingest vegetation analysis into our customer facing tools
At Overstory, our Staff Engineers are hands-on technical leaders whose influence extends beyond their team either through leading cross team initiatives, making technology choices for critical aspects of our technology platform or solving for critical technical challenges within teams enabling our business to achieve our rapid scaling plans (growing 3x YoY).
This role will start off being primarily team scoped solving critical scaling challenges. There is scope to expand remit as we grow.
Time zone requirement: Europe (GMT/WET, CET, EET) and Eastern North America (NST, AST, EST)
What You'll Do
Technical Skills:
- Broad and deep understanding of system design with an ability to select the correct paradigm/technology given the situation and constraints.
- Develops a deep understanding of our business domains and how technology can be applied to drive business impact.
- Innovates and introduces new technologies or methodologies.
- Resolves complex technical challenges with innovative solutions.
Ownership:
- Leads cross-team initiatives or leads on architectural system design at team level
- Drives pragmatic technology choices/decisions making sensible trade offs in order to balance current and future business needs.
- Defines coding standards and engineering best practices.
- Evaluates and recommends new tools and technologies.
- Hands-on contribution
Leadership:
- Mentors and coaches engineers.
- Influences technical decisions at the organizational level.
- Collaborates with product managers and CTO to inform how technology can influence or enable the product strategy.
Skills & Experience
- Experience of working in a high growth scaleup environment
- Product minded and able to demonstrate significant impact you have had on a business through the application of technology
- Proven experience of full stack development across the following (or similar) technologies: React/Typescript, Python/fastAPI, Postgres DB, Data pipelines)
- Comfortable working in a build it, run it environment (GCP, cloud run, grafana, k8s) - or similar
- Ability to design and implement scalable and resilient systems
- Strong leadership skills with the ability to mentor and coach engineers at all levels
- Excellent communication skills and ability to collaborate effectively in a cross-functional team environment
- Passion for learning and staying updated with evolving technologies and industry trends
Nice To Have
- Demonstrated experience scaling large distributed architectures
- Experience working in a remote-first environment
- Experience working with satellite data and/or imagery
Note: We believe that all people are capable of great things. We encourage you to apply even if you do not meet all of the requirements that are listed within this job description.
What We Offer
- Competitive, location-specific compensation and benefits
- Flexible, autonomous and collaborative working environment rooted in trust - we build our work days around our lives, not the other way around
- Home office stipend, coworking and ongoing education budgets
- A company culture that genuinely embodies each of our core values
- To be part of truly mission-driven work that reduces wildfires, protects earth’s natural resources and helps solve our climate crisis
About Our Team
We are a group of 100 people from all over the world. Fifteen nationalities are represented in our team and at last count we speak fourteen languages: English, Dutch, French, Spanish, German, Italian, Portuguese, Russian, Luxembourgish, Lithuanian, Bulgarian, Cantonese, Estonian, and Danish.
We work remotely from eleven countries and are looking for candidates that are living and working in one of them: United States, the Netherlands, United Kingdom, Ireland, Estonia, Portugal, France, Sweden, Switzerland, Denmark and Canada. We gather once a year in-person for our unforgettable team gathering event. We also offer the option to occasionally meet up for in-person collaboration.
Diversity & Inclusion
The climate crisis is a human crisis that requires diverse perspectives to solve.
We place enormous value on diversity and believe that the best ideas emerge when people with different backgrounds and experience work together. We remain committed to scaling a team that reflects the communities we serve, and strive to uphold equitable and inclusive practices across every aspect of our business. We are responsible for creating and maintaining a culture where everyone - regardless of background - has a voice in building a sustainable future.
Our Values
Tackling the climate crisis is our greatest mission.
We act with urgency.
Our curiosity fuels our growth.
We recognize that change is constant, and we find joy and power in exploration.
We’re rooted in diversity.
Just as ecosystems need biodiversity to thrive, our resiliency comes from our differences.
We care for each other.
We love the power of machines but we nurture each other as humans.
Trust is fundamental.
We assume the best in everyone, and we share ideas openly so that we have a positive impact.
_________________________________
Use of AI in Our Hiring Process
We sometimes use AI tools to support parts of our hiring process, such as helping us manage applications more efficiently or ensuring job descriptions are clear and inclusive. All hiring decisions are always made by people, not machines. Any data processed by AI is handled securely in line with GDPR and our Privacy Notice.
Ready to apply?
Apply to Overstory
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 with a strong preference for a candidate based in Portugal (Lisbon).
About the role
As a Staff Software Engineer at Fluxon, you'll drive the end-to-end delivery of products to market while learning, contributing, and growing in partnership with our leadership team
You'll be responsible for:
- Guiding project delivery all the way to the user, leading projects, building and iterating in a dynamic environment
- Partnering directly with clients to understand their needs, and achieve business goals
- Defining product requirements, identifying appropriate system designs and planning development in partnership with our Product and Design teams
- Supporting development of a healthy and effective engineering culture
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
- 7+ years of industry experience in software development
- Experience leading development through the full product lifecycle, including CI/CD, testing, release management, deployment, monitoring and incident response
- Fluent in the design and implementation of scalable system architectures, data structures and algorithms, and effective development practices
What we offer
- Remote-first, flexible work with a budget to set up a work space that works for you
- Localized healthcare coverage to support you and your family’s wellbeing
- Flexible paid time off with a minimum of 3 weeks per year (plus holidays)
- "No internal meetings" Fridays, so you can focus on deep, uninterrupted work
- A professional growth budget for learning that matters to you – whether it’s developing your technical skills or learning a new language
- A monthly wellness allowance to support your physical and mental health
- Annual company offsites, where we gather in person to build meaningful connections
- A competitive salary that reflects your expertise, impact and experience
- Profit-sharing, so you can benefit directly from the value we build together
- A paid sabbatical program, designed for rest, renewal and fresh perspective
Ready to apply?
Apply to Fluxon
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 with a strong preference for a candidate based in Portugal (Lisbon).
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
- Localized healthcare coverage to support you and your family’s wellbeing
- Flexible paid time off with a minimum of 3 weeks per year (plus holidays)
- "No internal meetings" Fridays, so you can focus on deep, uninterrupted work
- A professional growth budget for learning that matters to you – whether it’s developing your technical skills or learning a new language
- A monthly wellness allowance to support your physical and mental health
- Annual company offsites, where we gather in person to build meaningful connections
- A competitive salary that reflects your expertise, impact and experience
- Profit-sharing, so you can benefit directly from the value we build together
- A paid sabbatical program, designed for rest, renewal and fresh perspective
Ready to apply?
Apply to Fluxon