Senior Software Engineer — Security-First in Helsinki

Kultakiertue Oy; Helsinki; Hybrid; EUR 67,000 - 84,000; Full time

Benefits offered by this job

Hybrid work model

Office in Helsinki Käpylä

Unlimited AI tokens

Competitive salary & bonus

Job summary

Kultakiertue Oy, a Helsinki-based scale-up, seeks hands-on Senior Developers to join the in-house engineering team. Work with modern frameworks like SvelteKit, Vercel, Supabase and PostgreSQL to run our internal software end to end across routes, bookings, payments, compliance and more.

We prioritize security as a core product feature and aim to expand into new markets while maintaining data protection for multiple regulatory regimes.

Qualifications

• Proven track record building complex, mobile-first web apps (Svelte/SvelteKit or similar).
• Strong experience in backend and/or frontend development (Node.js, TypeScript, React, Vue or similar).
• Solid database and integration skills (PostgreSQL, REST APIs, row-level security a plus).
• A security-first mindset: authentication, authorization, PII handling and OWASP Top 10 as part of normal development.

Responsibilities

• Develop new features and integrations across internal apps.
• Plan and manage country-specific compliance and reporting requirements.
• Own security in day-to-day development: access control and secure handling of data.
• Contribute to secure architecture decisions, including threat modeling and code review.
• Build and maintain integrations across systems.
• Monitor workflows, data quality and system reliability.

Skills

SvelteKit

TypeScript

Node.js

REST APIs

Security-minded development

PostgreSQL

Tools

Vercel

Supabase

PostgreSQL

Job description

Kultakiertue Oy, a Helsinki-based scale-up, seeks hands-on Senior Developers to join the in-house engineering team. Work with modern frameworks like SvelteKit, Vercel, Supabase and PostgreSQL to run our internal software end to end across routes, bookings, payments, compliance and more.

We prioritize security as a core product feature and aim to expand into new markets while maintaining data protection for multiple regulatory regimes.