Senior Full Stack Engineer - Core UX

📍 Job Overview

Job Title: Senior Full Stack Engineer - Core UX

Company: Jobgether (for a partner company)

Location: Portugal

Job Type: Full-time, Contractor

Category: Engineering - Software Development / User Experience

Date Posted: 2026-09-04

Experience Level: Mid-Senior Level (5-10 years)

Remote Status: Remote OK (within Portugal)

🚀 Role Summary

• Focus on refining and enhancing product functionality with a strong emphasis on usability, consistency, responsiveness, performance, and visual quality to deliver a premium user experience.

• Design, develop, debug, and maintain scalable full-stack solutions that support evolving product requirements, blending frontend expertise with backend engineering.

• Collaborate closely with a globally distributed team of full-stack, data, machine learning, and DevOps engineers on complex, high-impact industry software and AI-powered solutions.

• Take end-to-end ownership of projects, driving initiatives from problem definition through implementation and completion with minimal oversight, demonstrating resilience and initiative.

• Contribute to a culture centered on high standards, customer impact, transparency, accountability, continuous experimentation, and technical excellence in a fast-paced growth environment.

📝 Enhancement Note: This role is a Senior Full Stack Engineer position with a specialized focus on Core User Experience (UX). While the primary function is engineering, the emphasis on "Core UX" signifies a deep involvement in how users interact with the product daily, requiring a keen eye for detail, performance, and intuitive design principles. The "Contractor" employment type, alongside Full-time, suggests potential for flexible engagement models. The role is remote within Portugal, indicating a need for strong self-management and communication skills.

📈 Primary Responsibilities

• Refine and enhance existing product functionality with a strong focus on usability, consistency, responsiveness, performance, and visual quality.

• Improve the overall user experience by paying close attention to layouts, interactions, interface behavior, and product polish.

• Design, develop, debug, and maintain scalable full-stack solutions that support evolving product requirements.

• Contribute to frontend development using modern frameworks, with React experience particularly valuable.

• Develop and maintain backend functionality, including serverless architectures, asynchronous workflows, and cloud-based services.

• Work effectively with relational databases and contribute to reliable, scalable data solutions.

• Collaborate closely with full-stack, data, machine learning, and DevOps engineers across a globally distributed team.

• Take end-to-end ownership of projects, driving initiatives from initial problem definition through implementation and completion with minimal oversight.

• Proactively communicate progress, surface blockers, ask thoughtful questions, and keep relevant stakeholders informed.

• Experiment with new approaches, measure results, and iterate rapidly to solve complex or previously unsolved technical and product challenges.

• Contribute to a culture centered on high standards, customer impact, transparency, accountability, continuous experimentation, and technical excellence.

📝 Enhancement Note: The responsibilities highlight a blend of traditional full-stack development with a strong UX sensibility. The emphasis on "end-to-end ownership," "proactive communication," and "experimentation" points to a role requiring a high degree of autonomy and a results-oriented mindset, typical of senior engineering positions in agile, growth-stage environments.

🎓 Skills & Qualifications

Education: Not explicitly stated, but a Bachelor's or Master's degree in Computer Science, Engineering, or a related field is typically expected for this level of experience.

Experience: 5+ years of professional software engineering experience, with a proven track record of improving and polishing product functionality to deliver a premium user experience.

Required Skills:

• Strong software engineering fundamentals, including system design, debugging, architecture, and structured problem-solving.

• Professional experience with a modern frontend framework, preferably React.

• Strong knowledge of JavaScript, TypeScript, and/or Python; candidates with equivalent experience in other object-oriented programming languages are also encouraged to apply.

• Experience with serverless technologies and cloud environments, including platforms or services such as AWS Lambda and EC2.

• Experience designing or working with asynchronous workflows and scalable backend systems.

• Solid experience with relational databases, ideally PostgreSQL.

• Strong attention to detail and a genuine appreciation for high-quality, polished user experiences.

• Demonstrated ownership, initiative, resilience, and the ability to drive projects forward with limited supervision.

• Excellent communication skills and a proactive approach to collaboration in a distributed, cross-functional environment.

• Comfortable experimenting, measuring outcomes, learning quickly, and iterating on challenging problems.

• Authorization to work in the European country where you are based; the role is offered through a B2B or contractor arrangement, and visa sponsorship is not available. Preferred Skills:

• Experience with LLMs, generative AI, or distributed systems is a valuable advantage.

• Ability to thrive in a fast-paced growth environment with ambitious goals and a high degree of responsibility.

📝 Enhancement Note: The experience requirement is clearly defined at 5+ years. The preference for React and specific mention of JavaScript, TypeScript, and Python, along with AWS Lambda, EC2, and PostgreSQL, indicate the core technology stack. The emphasis on "strong software engineering fundamentals" and "structured problem-solving" is crucial for a senior role. The requirement for work authorization within Europe and the contractor arrangement are critical logistical details.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• Demonstrations of refined product functionality, showcasing improvements in usability, responsiveness, performance, and visual quality.

• Examples of scalable full-stack solutions developed, highlighting both frontend (ideally React) and backend components.

• Case studies involving serverless architectures, asynchronous workflows, and cloud-based services (e.g., AWS Lambda).

• Evidence of working with relational databases, such as PostgreSQL, to build reliable data solutions.

• Projects that showcase a strong attention to detail and a commitment to high-quality, polished user experiences. Process Documentation:

• Showcase of structured problem-solving methodologies applied to complex technical challenges.

• Examples of end-to-end project ownership, from initial problem definition through implementation and completion.

• Documentation or presentation of experimentation processes, including how results were measured and iterated upon.

• Evidence of proactive communication and collaboration within distributed, cross-functional teams.

📝 Enhancement Note: While a formal "portfolio" isn't explicitly requested, the job description heavily implies that candidates will need to demonstrate their capabilities through past projects and experiences. The "Accountabilities" section directly translates into what a candidate should be prepared to showcase in their resume, cover letter, or during interviews, especially regarding UX polish, full-stack development, cloud services, and ownership.

💵 Compensation & Benefits

Salary Range: $80,000 to $165,000 USD per year, depending on experience, performance, and geographic location.

Benefits:

• Significant equity options package.

• 20 days of paid time off per year.

• Global team offsites and opportunities to connect with colleagues internationally.

• Phone reimbursement.

• Gym reimbursement.

• Student stipend.

• Opportunity to work alongside ambitious, highly skilled professionals across engineering, data, machine learning, and DevOps.

• Significant individual impact within a small, high-performing team.

• Opportunity to work on challenging technology and AI problems while helping transform a major global industry.

• An environment that emphasizes ownership, experimentation, transparency, continuous learning, and measurable customer impact.

Working Hours: Standard full-time hours are implied, with flexibility expected due to the remote, global nature of the team and the contractor arrangement. The AI-derived value suggests approximately 40 hours per week, but the emphasis on ownership and results may lead to variable hours.

📝 Enhancement Note: The salary range is provided in USD, which is common for international remote roles. The "Contractor" employment type means benefits like health insurance, retirement plans, and paid time off may differ from standard full-time employment and could be managed by the contractor directly or through the B2B arrangement. The explicit mention of "20 days of paid time off" is a specific benefit, though its application for contractors may vary. The "Equity options" are a significant component, often associated with growth-stage companies.

🎯 Team & Company Context

🏢 Company Culture

Industry: The company operates in a complex, high-impact industry, leveraging sophisticated software and AI-powered solutions. The specific industry is not named but is described as a "major global industry" undergoing transformation.

Company Size: The description mentions a "small, high-performing team" and a "fast-paced growth environment," suggesting the partner company is likely a growing startup or a dynamic division within a larger organization. Jobgether's own size is not detailed but it acts as a platform.

Founded: The founding date of the partner company is not provided. Jobgether's founding date is not provided.

Team Structure:

• The Core UX team is small and high-performing, working closely with other specialized engineering teams (full-stack, data, machine learning, DevOps).

• Collaboration is key within a globally distributed team.

• The reporting structure is not detailed but senior engineers are expected to take "end-to-end ownership" and drive initiatives with "minimal oversight," implying a flat or agile structure. Methodology:

• Data-driven decision-making is emphasized through "experiment with new approaches, measure results, and iterate rapidly."

• A focus on "customer impact" and "measurable customer impact" drives development efforts.

• Continuous learning and experimentation are core tenets.

• Agile development practices are implied by the fast-paced environment and iterative approach.

Company Website: Jobgether: jobgether.com (platform), Partner company details are managed through Jobgether.

📝 Enhancement Note: The focus on "sophisticated software and AI-powered solutions" and a "complex, high-impact industry" suggests a B2B SaaS or enterprise software company. The culture described by Jobgether (ownership, experimentation, transparency, accountability, continuous learning, customer impact) is highly desirable for engineers seeking challenging and impactful work.

📈 Career & Growth Analysis

Operations Career Level: This is a Senior Full Stack Engineer role, indicating a high level of technical expertise and autonomy. It sits within the engineering function, not directly in Revenue or Sales Operations, but contributes to the overall GTM strategy through product development and user experience.

Reporting Structure: Likely reports to an Engineering Manager or Lead within the Core UX team or a broader engineering leadership structure. The emphasis on minimal oversight suggests a high degree of autonomy.

Operations Impact: While not a direct "operations" role, the engineer's work on Core UX directly impacts user adoption, retention, and satisfaction, which are critical drivers of revenue and business growth. A polished, intuitive user experience is fundamental to a successful Go-To-Market strategy.

Growth Opportunities:

• Technical Specialization: Deepen expertise in React, full-stack development, serverless architectures, AI/ML integration, and distributed systems.

• Leadership: Potential to grow into a Tech Lead or Engineering Manager role, guiding smaller teams or specific projects.

• Strategic Influence: Contribute to product strategy and technical decision-making due to the significant influence of the role and team.

• Industry Exposure: Gain experience in a complex, high-impact industry and work with cutting-edge AI technologies.

📝 Enhancement Note: This role offers significant growth potential within a specialized engineering track, with opportunities to influence product direction and potentially move into leadership. The impact on the business is indirect but substantial, as user experience is a key differentiator in competitive markets.

🌐 Work Environment

Office Type: The role is advertised as "Remote OK" and specifically located within Portugal. This implies a remote-first or hybrid model where the employee is based in Portugal and works remotely.

Office Location(s): Portugal. Specific city details are not provided.

Workspace Context:

• A globally distributed team environment requiring strong virtual collaboration tools and practices.

• Emphasis on asynchronous communication and self-management.

• Access to modern development tools and cloud infrastructure (AWS).

• Opportunities for international connection through global team offsites.

Work Schedule: While approximately 40 hours per week is implied, the emphasis on ownership and results suggests flexibility. Candidates should be prepared for potential variations in working hours to meet project deadlines or collaborate with team members in different time zones.

📝 Enhancement Note: The remote nature within Portugal is a key feature. Candidates should be comfortable with asynchronous communication and self-directed work. The mention of "global team offsites" indicates that occasional in-person interaction with the broader team is a possibility, which can be a significant benefit for networking and team building.

📄 Application & Portfolio Review Process

Interview Process:

• Application Screening: AI-powered matching process by Jobgether to identify top candidates based on core requirements.

• Initial Review: Shortlisted candidates are shared directly with the hiring company's internal team.

• Technical Assessment: Likely includes a combination of coding challenges, system design discussions, and problem-solving exercises. Given the "Core UX" focus, expect questions related to user experience principles, performance optimization, and interface design.

• Behavioral Interviews: Assessment of ownership, initiative, resilience, communication, and collaboration skills, particularly within a distributed team context.

• Team/Hiring Manager Interviews: Deeper dive into technical expertise, problem-solving approach, and cultural fit with the partner company's team.

Portfolio Review Tips:

• Showcase UX Impact: Highlight projects where you significantly improved user experience, focusing on measurable results (e.g., increased conversion rates, reduced bounce rates, improved task completion times).

• Demonstrate Full-Stack Capabilities: Present projects that clearly illustrate your ability to work across the entire stack, from frontend UI implementation to backend logic and database management.

• Highlight Cloud & Serverless Experience: Provide examples of applications built using cloud platforms (AWS) and serverless architectures (Lambda), emphasizing scalability and efficiency.

• Detail Ownership and Problem-Solving: Use case studies to explain how you took ownership of complex problems, your structured approach to solving them, and the outcomes achieved.

• Quantify Achievements: Whenever possible, use metrics to demonstrate the impact of your work. For example, "reduced page load time by X%" or "increased user engagement by Y%."

Challenge Preparation:

• Refine Core Technologies: Ensure strong command of React, JavaScript/TypeScript, Python, and SQL.

• System Design Practice: Prepare for system design questions, focusing on scalability, reliability, and performance, particularly for web applications and microservices.

• UX Principles: Brush up on core UX principles, performance optimization techniques for web applications, and best practices for creating responsive and intuitive interfaces.

• Communication & Collaboration: Practice articulating technical concepts clearly and concisely, and be ready to discuss how you collaborate effectively in remote, cross-functional teams.

📝 Enhancement Note: The Jobgether platform uses AI for initial screening, so optimizing keywords on your resume and cover letter related to the "AI Key Skills" is crucial. The emphasis on "Core UX" means interviewers will likely probe deeply into your understanding of user-centric design and your ability to translate that into technical solutions.

🛠 Tools & Technology Stack

Primary Tools:

• Frontend: React (preferred), JavaScript, TypeScript.

• Backend: Python (preferred), other object-oriented languages.

• Cloud: AWS (Lambda, EC2), serverless technologies.

• Databases: Relational databases, PostgreSQL (ideally).

• Architecture: Asynchronous workflows, scalable backend systems, distributed systems.

Analytics & Reporting: Not explicitly mentioned, but implied through the need to "measure results" and "iterate rapidly." Candidates may use browser developer tools, application performance monitoring (APM) tools, and potentially custom logging/analytics.

CRM & Automation: Not explicitly mentioned as primary tools for this role, but understanding how the product integrates with CRM or marketing automation platforms could be beneficial.

📝 Enhancement Note: The core technology stack is well-defined. Candidates should be prepared to discuss their experience with these specific technologies, especially React and serverless AWS services. Familiarity with tools that aid in performance analysis and debugging for frontend applications would also be advantageous.

👥 Team Culture & Values

Operations Values:

• High Standards: A commitment to delivering high-quality, polished, and exceptional user experiences.

• Customer Impact: Focusing on solutions that directly benefit users and contribute to business success.

• Transparency: Open communication about progress, blockers, and decisions.

• Accountability: Taking ownership of work and driving initiatives to completion.

• Continuous Experimentation: A willingness to try new approaches, learn from failures, and iterate quickly.

• Technical Excellence: A dedication to robust engineering practices and well-designed systems.

Collaboration Style:

• Distributed & Cross-functional: Working effectively with engineers across different disciplines (full-stack, data, ML, DevOps) and geographical locations.

• Proactive Communication: Encouraging thoughtful questions, surfacing blockers early, and keeping stakeholders informed.

• Ownership-driven: Engineers are expected to take initiative and drive projects forward with minimal supervision, implying a collaborative environment where ideas are shared and debated constructively.

📝 Enhancement Note: The company culture described is typical of modern, agile tech companies that prioritize innovation, employee growth, and impactful work. The emphasis on "experimentation" and "continuous learning" is particularly strong.

⚡ Challenges & Growth Opportunities

Challenges:

• Balancing UX Polish with Scalability: Ensuring a highly polished user experience while building scalable and maintainable full-stack solutions.

• Working in a Fast-Paced Growth Environment: Adapting to rapid changes, ambitious goals, and a high degree of responsibility.

• Cross-Time Zone Collaboration: Effectively communicating and collaborating with a globally distributed team.

• Transforming a Major Industry: Contributing to significant technological advancements in a complex, high-impact sector.

• AI Integration: Working with and potentially developing solutions involving LLMs and generative AI.

Learning & Development Opportunities:

• Advanced Technical Skills: Deepening expertise in modern frontend frameworks, cloud-native architectures, serverless computing, and potentially AI/ML technologies.

• Product Strategy Influence: Gaining exposure to product development and strategic decision-making processes.

• Leadership Development: Opportunities to mentor junior engineers or lead specific technical initiatives.

• Industry Insight: Understanding the nuances and challenges of a "complex, high-impact industry."

📝 Enhancement Note: The challenges are framed as opportunities for growth. The role is positioned to allow engineers to tackle complex technical problems while also developing soft skills related to leadership, strategy, and cross-cultural collaboration.

💡 Interview Preparation

Strategy Questions:

• "Describe a time you significantly improved the usability or performance of a product. What was your approach, and what were the results?" (Focus on UX polish, metrics, and ownership.)

• "Walk us through the design and implementation of a scalable full-stack feature you owned from concept to deployment. What technologies did you use, and why?" (Focus on full-stack skills, system design, and end-to-end ownership.)

• "How do you approach balancing rapid iteration and experimentation with maintaining code quality and system stability?" (Focus on experimentation, measurement, and technical excellence.)

• "Describe a complex technical challenge you faced in a distributed team environment. How did you communicate, collaborate, and resolve it?" (Focus on communication, collaboration, and problem-solving.) Company & Culture Questions:

• "What interests you about working on 'Core UX' and contributing to a 'complex, high-impact industry'?" (Showcase understanding of the role's impact and industry context.)

• "How do you stay current with new technologies and best practices in frontend and backend development?" (Demonstrate continuous learning and passion.)

• "Describe your ideal team culture. How do you contribute to a positive and productive team environment?" (Align with company values of ownership, transparency, and collaboration.) Portfolio Presentation Strategy:

• Structure: Prepare 2-3 key projects that best showcase your full-stack skills, UX impact, and experience with the required technologies. Use a STAR (Situation, Task, Action, Result) or similar framework.

• Metrics: Quantify the impact of your work wherever possible (e.g., performance improvements, user engagement metrics).

• Technical Depth: Be ready to dive deep into the technical details of your projects, explaining architectural decisions, trade-offs, and problem-solving approaches.

• UX Focus: Clearly articulate how your technical contributions enhanced the user experience and why those enhancements were important.

📝 Enhancement Note: Interview preparation should focus on demonstrating not just technical proficiency but also strong problem-solving, communication, and ownership skills, all within the context of user experience and a distributed team environment.

📌 Application Steps

To apply for this Senior Full Stack Engineer - Core UX position:

• Submit your application through the provided link on jobs.lever.co.

• Tailor your resume: Highlight specific experience with React, JavaScript/TypeScript, Python, AWS Lambda, PostgreSQL, and serverless architectures. Emphasize projects where you improved user experience, performance, and scalability.

• Prepare your portfolio: Select 2-3 strong projects that demonstrate your full-stack capabilities, attention to detail in UX, and ownership of complex tasks. Be ready to discuss them in detail, focusing on quantifiable results.

• Research the company: Understand the nature of the "complex, high-impact industry" and the partner company's mission if possible. This will help tailor your responses and demonstrate genuine interest.

• Practice interview questions: Prepare answers to common technical, behavioral, and situational questions, focusing on demonstrating ownership, problem-solving, and collaboration in a remote setting.

⚠️ Important Notice: This enhanced job description includes AI-generated insights and operations industry-standard assumptions. All details should be verified directly with the hiring organization before making application decisions.