Staff Software Engineer (Payments)

About the Position

We are looking for a Staff Software Engineer (Payments) to join Kilo, a fast-scaling travel startup with strong product-market fit. This role is ideal for a builder who is excited to lead the migration of our platform to AWS and build scalable backend systems.

About the Team

Breakneck Studio – an incubator and accelerator scaling digital and e-commerce brands at high velocity. It's home to our Co-Found program, where ambitious founders take products from zero to market in months, not years. This is where you get hands-on, zero-to-scale experience you won't find in a regular job.

We are a fast-scaling travel startup with strong product-market fit, a generational traveltech company looking to disturb this sleepy industry. We are two-sided: travelers get a consumer product that helps them plan and book trips, and advisors get a SaaS-style subscription with certification and qualified leads in the offer.

Responsibilities

• Lead the migration of our platform to AWS, from planning the architecture to executing the cutover with minimal downtime.
• Own the migration of our PHP/Laravel backend to AWS, deciding what moves as-is and what gets re-architected along the way.
• Design and build background processing for our payment flows: queues and workers that never lose state, handle retries and idempotency correctly, and recover cleanly from failure.
• Ensure every job and transaction is traceable and auditable, so nothing goes missing between systems.
• Build infrastructure that scales with demand, including autoscaling workers, managing load spikes, and keeping costs under control as we grow.
• Set up infrastructure as code, CI/CD pipelines, and environments (dev, staging, prod) that let the team ship quickly and safely.
• Put monitoring, logging, and alerting in place so problems are caught early and diagnosed fast.
• Own security and reliability across the infrastructure, including access control, secrets management, backups, and disaster recovery.
• Strengthen the backend foundations of our TypeScript, Supabase (PostgreSQL), and TanStack stack so it can support production scale.
• Work directly with the founder and early team on infrastructure decisions that affect the product, and set the standards future engineers will build on.

Requirements

• Strong software engineering fundamentals, with deep experience in Platform / Cloud Engineering (AWS) and Backend Software Engineering (PHP, Laravel, PostgreSQL).
• Deep, hands-on AWS expertise, especially SQS (standard and FIFO, visibility timeouts, DLQs), S3 (lifecycle policies, access control, presigned URLs, event notifications), and related services such as Lambda, ECS/Fargate, IAM, EventBridge, and CloudWatch.
• Production experience with PHP and Laravel, including Laravel Queues, Horizon or equivalent, and designing backend services on PostgreSQL.
• Proven track record building highly reliable worker and queue systems: retry strategies with exponential backoff, idempotent job design, exactly-once or effectively-once processing, dead-letter queues, and state handling that survives crashes, deploys, and partial failures.
• Experience planning and delivering complex platform migrations with minimal downtime, ideally including moving from a managed platform such as Supabase to self-managed AWS infrastructure.
• Strong Infrastructure as Code experience with Terraform, AWS CDK, or Pulumi, plus CI/CD pipeline design.
• Strong understanding of observability and operational excellence: metrics, logging, tracing, alerting, and incident response, using tools such as Datadog.
• Solid understanding of modern authentication and identity concepts (OAuth2, OIDC, SAML) and cloud security best practices, including IAM least privilege and secrets management.
• TypeScript experience is an advantage, as it is the team's primary development language.
• Comfortable in an agile, collaborative environment and communicating effectively with technical and non-technical stakeholders.
• Experience leading technical initiatives, influencing architectural decisions, or providing technical leadership across teams.

We Offer

• Competitive Salary: Gross salary range is 6000-8000 EUR/month + stock options (ESOP) depending on your experience.
• Location: Vilnius, Lithuania (4 days onsite, 1 day remote hybrid model). Other locations available.
• Perks:
  • Own your wellness: Health insurance (after probation), on-site physiotherapist, office gym, fitness classes, 7 extra days off, 3 for weddings, hybrid work, and the freedom to work 2 months from anywhere in the world.
  • Boost your daily life: Pet-friendly office, fresh breakfasts, hot lunches, stocked drawers and fridges, rooftop and cellar events, 10 social clubs, public transport card for Vilnius, and Perks.lt perks.
  • Shape your growth path: Coaching, mentorship, training, conferences, online courses, subscriptions, books – you’ve got a €1000 yearly budget to fuel personal or team growth.
  • Drive global impact: Build impact across 30+ brands worldwide. Launch bold projects. Even step in as a co-founder – we reward those who push further. And if you bring in more great people, you get €1500 for every successful referral.

About the Company

Kilo is a fast-scaling travel startup with strong product-market fit, a generational traveltech company looking to disturb this sleepy industry. We are two-sided: travelers get a consumer product that helps them plan and book trips, and advisors get a SaaS-style subscription with certification and qualified leads in the offer.

Additional conditions apply based on your residence location.

Department: Tech

Location: Vilnius

Seniority: Senior

Team: Breakneck Studio

Employment type: Full-time