Senior Fullstack Developer

Reaktor Innovations Oy; Amsterdam; Hybrid; EUR 70,000 - 110,000; Full time

Benefits offered by this job

Top-spec computer and phone for work

Phone & internet: unlimited plan

7% pension plan

Extensive health insurance

Mental health support

Wellbeing benefit with YourCampus

NS commuting card

Equal opportunity employer

Job summary

Reaktor Amsterdam is seeking a senior fullstack engineer to build and improve modern web applications, backend services, APIs and data models. You will work across frontend, backend and infrastructure, guiding clients on technology choices and delivery approaches while contributing to cloud environments, CI/CD pipelines and production operations.

The role emphasizes hands-on contribution, collaboration with client teams and stakeholders, and delivering production-grade software in an

Qualifications

• Experience with modern frontend development using TypeScript/React.
• Backend service development experience with Node.js/Java/Python/Kotlin.
• Proven track record shipping production-grade digital products.
• Comfortable across the full delivery lifecycle: implementation to testing, deployment and production operations.
• Understanding of cloud environments and CI/CD, deployments, and production operations.
• Ability to work directly with clients, stakeholders and other disciplines in a senior, consultative role.
• Strong problem-solving skills and the ability to bring clarity to ambiguous product or technical situations.
• Hands-on mindset, actively contribute to the work and help the team move forward.
• Fluent written and spoken English.
• No fixed years of experience; typically several years of professional experience.

Responsibilities

• Building and improving modern web applications, backend services, APIs and data models.
• Working across frontend, backend and infrastructure depending on client project needs.
• Helping clients choose suitable technologies, architecture and delivery approaches.
• Contributing to cloud environments, CI/CD pipelines, deployments and production operations.
• Debugging, testing, monitoring and improving production-grade systems.
• Working on products or tooling related to customer-facing services, internal platforms, identities, martech, customer support, analytics, content, online stores, integrations, developer tooling or SDKs.
• Collaborating with client tech teams, business stakeholders, designers, product people and other disciplines.
• Clarifying ambiguous requirements and turning them into working software.
• Taking responsibility for delivery while supporting the team.
• Using modern development practices, including openness to AI-assisted development tools and workflows.

Skills

TypeScript

React

Node.js

Java

Kotlin

Python

Client-facing

Tools

CI/CD pipelines

Cloud platforms

Job description

Your daily tasks may include:

• Building and improving modern web applications, backend services, APIs and data models
• Working across frontend, backend and infrastructure depending on the needs of the client project
• Helping clients choose suitable technologies, architecture and delivery approaches
• Contributing to cloud environments, CI/CD pipelines, deployments and production operations
• Debugging, testing, monitoring and improving production-grade systems
• Working on products or tooling related to customer-facing services, internal platforms, identity, martech, customer support, analytics, content, online stores, integrations, developer tooling or SDKs
• Collaborating directly with client tech teams, business stakeholders, designers, product people and other disciplines
• Clarifying ambiguous requirements and turning them into working software
• Taking responsibility for delivery while making sure the team is supported and no one is left behind
• Using modern development practices, including openness to AI-assisted development tools and workflows

To thrive in this position, you’ll need:

Must-haves

• Strong experience in modern frontend development, for example with TypeScript and React or comparable technologies
• Strong experience in backend service development, for example with Node.js, Java, Kotlin, Python or comparable technologies
• Experience building, shipping and improving production-grade digital products
• Comfortable working across the full delivery lifecycle, from implementation to testing, deployment and production operations
• Understanding of cloud environments, CI/CD, deployments and how production systems are operated
• Ability to work directly with clients, stakeholders and other disciplines in a senior, consultative role
• Strong problem-solving skills and the ability to bring clarity to ambiguous product or technical situations
• A hands-on mindset - you are technically credible, actively contribute to the work and help the team move forward
• Fluent verbal and written English skills to collaborate in an international environment
• We do not have a hard requirement around years of experience, but we have noticed that this level of fullstack, client-facing and production ownership usually takes several years of professional experience to build.

Nice-to-haves

• Experience from customer-facing digital products, online services, ecommerce, subscriptions, internal platforms, analytics, content, martech or similar product domains
• Experience with high-traffic or business-critical production systems
• Deeper experience with platform engineering, infrastructure-as-code or DevOps practices
• Experience with customer-facing products, internal tools, integrations, SDKs or developer tooling
• Familiarity with mobile development
• Adaptability
• Willingness to work in a hybrid setup. This means balancing office, client premises and remote work depending on the client project and team needs.

Benefits

At Reaktor Amsterdam, our benefits and perks evolve with our community, and we're always open to new ideas that will support the wellbeing of Reaktorians. Currently, we offer the following perks:

• Tools: a top-spec computer and a phone to work with and use at work and home
• Phone & internet: unlimited phone plan and home internet
• 7% pension plan
• Extensive health insurance
• Mental health support
• Wellbeing benefit with YourCampus
• Commuting benefit with NS card
• We're an equal opportunity employer

Strong experience in modern frontend development with TypeScript and React or comparable technologies, Strong experience in backend service development with Node.js, Java, Kotlin, Python or comparable technologies, Experience building, shipping and improving production-grade digital products, Comfortable with full delivery lifecycle: implementation, testing, deployment, production operations, Understanding of cloud environments, CI/CD, deployments and production operations, Ability to work directly with clients, stakeholders and other disciplines in a senior, consultative role, Strong problem-solving skills and ability to bring clarity to ambiguous situations, Hands-on mindset and active contribution to the team, Fluent written and spoken English