Full-Time

Backend Engineer

Fintech

Updated on 9/4/2026

A11

A11

Hands-on operations for scaling tech startups

No salary listed

Berlin, Germany

In Person

This position is based onsite in Berlin.

Category
Software Engineering (1)
Required Skills
Python
GitHub Actions
Node.js
Java
Kinesis
Postgres
Data Engineering
TypeScript
AWS
Terraform
Spring

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Requirements
  • At least 5–7 years of backend engineering experience with meaningful exposure to FinTech, payments, or financial data systems.
  • Strong proficiency in Java and Spring Boot, with a deep understanding of transactional systems and data consistency.
  • Solid experience with PostgreSQL, including schema design, indexing, and query optimization for financial data.
  • Experience integrating with payment processors such as Stripe or Adyen, or with open banking APIs.
  • Experience designing and implementing backend systems for financial operations.
  • Experience with rigorous testing practices and reliable failure handling in financial flows.
Responsibilities
  • Design and implement backend services for payment processing, invoicing, reconciliation, and smart financial reporting.
  • Build robust, auditable data pipelines that ensure accuracy and traceability across financial operations.
  • Develop and maintain integrations with payment gateways, banking APIs, and financial data providers.
  • Enforce data integrity standards and implement idempotency, retry logic, and failure-handling patterns in financial flows.
  • Collaborate with compliance and product teams to translate regulatory requirements into technical implementations.
  • Contribute to fraud detection logic, rate limiting, and access-control mechanisms protecting financial operations.
  • Own incidents end-to-end by investigating and resolving them and driving post-mortems to improve system reliability.
Desired Qualifications
  • Performance-based bonus program.

A11 embeds its team of experienced operators into fast-growing tech companies to act as an external operations team that drives internal growth. By working alongside founders and business leaders, A11 helps scale various functions from within the client organization, using hands-on, in-house leadership to accelerate expansion. The product works by integrating its operators into the client’s teams, taking on operational roles and driving change across functions such as growth, product, and operations, effectively serving as interim management and growth consulting. What sets A11 apart from competitors is its bench of operators who have already scaled companies to billion-dollar valuations and its ability to embed deeply into a company’s day-to-day operations, rather than offering purely advisory services. Its goal is to help founders navigate rapid growth, optimize scaling processes, and build the operational capabilities needed to achieve large-scale success.

Company Size

N/A

Company Stage

N/A

Total Funding

N/A

Headquarters

N/A

Founded

2025

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Simplify Jobs

Simplify's Take

What believers are saying

  • A11’s Berlin recruiting stayed hot, with 45-plus live roles in September 2026.
  • ARX Robotics raised a €42 million Series A after A11 built its team.
  • Trade Republic launched new trading technology in July 2026, sustaining A11 relevance.

What critics are saying

  • Clients internalize A11’s playbook, shrinking recurring demand by 2027.
  • A11 still depends on founder-led relationships, especially Jan Miczaika and Moritz Claussen.
  • Losing Trade Republic or Sennder would break the reference flywheel and threaten viability.

What makes A11 unique

  • Jan Miczaika and Moritz Claussen bring Wooga and cargo.one scaling credibility.
  • A11 embeds operators directly inside clients, not an external slide-deck consultancy.
  • Public proof points include Trade Republic, Sennder, and ARX Robotics team builds.

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Benefits

Flexible Work Hours

Paid Vacation

Holiday Breaks?

Remote Work Options

Wellness Program