Fullstack Engineer, Investigator Tools

Sardine

. Drive the product lifecycle from determining the initial problem space and user needs, to technical modeling, UX execution, and iterative improvements based on vague requirements .

Posted 10/14/2026full-timeRemote • GermanyMid-LevelSenior💰 €125,000 - €139,000 per yearWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in building data-intensive applications and advanced graph systems, with a strong focus on writing efficient, production-ready code in TypeScript, Node.js, and React. Proven ability to take ownership of complex problems and deliver scalable features in a fast-paced environment.

Highest-signal resume keywords

TypeScriptNode.jsReactData ModelingData Pipelines

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

Efficient Code WritingData-Intensive ApplicationsComplex WorkflowsBig DataTechnical ModelingGraph SystemsPerformance OptimizationBug DiagnosisFeature OwnershipScalable Features

Soft Skills

CollaborationProblem SolvingOwnershipExecutionAdaptability

Industry Keywords

Fraud DetectionUser ExperienceStartup EnvironmentAmbiguous ProblemsIterative Improvements

Tech Stack

Tools & technologies

JavaScriptNode.jsReactTypeScriptGo

About the role

Key responsibilities & impact

Drive the product lifecycle from determining the initial problem space and user needs, to technical modeling, UX execution, and iterative improvements based on vague requirements
Build complex technical systems into intuitive, user-friendly interfaces
Develop and optimize advanced graph systems to visualize fraud rings
Build performant search tools to help analysts rapidly identify suspicious transactions
Collaborate with Design, Data, Product, and Account Management teams
Proactively diagnose, triage, and resolve bugs
Write highly efficient and performant code
Build data-intensive applications, including advanced graph systems used to uncover complex fraud rings
Own features end-to-end at massive scale to empower fraud analysts to investigate suspicious transactions faster

Requirements

What you’ll need

Extensive experience writing efficient, production-ready code in TypeScript, Node.js, React, Go and other server programming languages
Proven experience working with data-intensive applications, complex workflows, and big data at scale
Deep background in technical data modeling and building robust production data pipelines
Ability to thrive, execute, and deliver consistently in a fast-paced, high-growth startup environment
Proven track record of taking extreme ownership of ambiguous problems and independently turning them into polished, scalable features

Benefits

Comp & perks

Generous compensation in cash and equity
Early exercise for all options, including pre-vested
Work from anywhere: Remote-first Culture
Flexible paid time off and Year-end break
Health insurance, dental, and vision coverage for employees and dependents - US and Canada specific
4% matching in 401k / RRSP - US and Canada specific
MacBook Pro delivered to your door
One-time stipend to set up a home office — desk, chair, screen, etc.
Monthly meal stipend
Monthly social meet-up stipend
Annual health and wellness stipend
Annual Learning stipend