Senior Software Engineer — XCore (Europe)

People AI; Polska; On-site; PLN 240,000 - 360,000; Full time

Job summary

Backstory.ai is seeking a Senior Software Engineer to own the foundational backend layer. You will design and scale low-latency APIs and distributed services for identity, authorization, audits, and BI exports, partnering with Product to shape requirements.

You will build data pipelines moving massive data volumes with consistency, implement logging and observability, and drive engineering excellence across teams.

Qualifications

• 5+ years of professional experience building backend systems in an enterprise environment.
• 2+ years of programming in Python or Scala.
• Experience building and orchestrating microservices and service-oriented architectures (SOA).
• Deep understanding of databases, caching strategies, and low-latency service design.
• Experience designing clean, scalable APIs with focus on client and end-user experience.

Responsibilities

• Design, build, and maintain highly performant, low-latency APIs and distributed microservices for identity, authorization, profiles, settings, and configurations.
• Own features end-to-end from product collaboration to system design, implementation, and production monitoring.
• Design data pipelines handling massive data with guaranteed consistency and zero data loss, including audit logs and BI exports.
• Maintain and improve features based on user feedback and evolving requirements.
• Advocate for engineering best practices: structured logging, cross-service tracking, robust error management, and observability.
• Build internal tooling to reduce manual operations and enable customer support self-service.
• Collaborate with Product, Design, and Engineering with clear communication.

Skills

Backend systems

Microservices

APIs

Databases & caching

Python/Scala

Data pipelines

Spark

Cross-functional collaboration

Job description

As a Senior SWE on the XCore team you will own the foundational layer that every other product at Backstory.ai is built on. From identity and authorization to audit logging and BI data exports, the systems you design set the standard for how the entire engineering organization builds and scales. This is a true end-to-end ownership role — you'll partner directly with Product to challenge and shape requirements, architect low-latency distributed services that move massive amounts of data with absolute consistency, and see your technical decisions ripple across the entire product. If you're the kind of engineer who takes pride in getting the foundations right and wants a high-visibility platform to champion engineering excellence, this is the role for you.

What you will do:

Design, build, and maintain highly performant, low-latency APIs and distributed microservices handling identity, authorization, user profiles, settings, and product configurations. Own features end-to-end: from partnering with Product to shape and challenge requirements, through system design, implementation, and production monitoring. Design and execute data pipelines that move massive volumes of data with guaranteed consistency and zero data loss, including audit-log systems and BI data exports. Maintain and improve existing features based on user feedback and evolving product requirements. Advocate for and introduce engineering best practices, including structured logging, cross-service request tracking, and robust error management. Ensure high-quality observability through alerting, dashboards, tracing, and runbooks for all production services. Build reusable internal tooling to reduce manual operations for engineering teams and enable customer support self-service. Collaborate cross-functionally with Product, Design, and Engineering teams with clear and concise communication.

What you will bring:

5+ years of professional experience building backend systems in an enterprise environment 2+ years of experience programming in Python or Scala Proven experience building and orchestrating microservices and service-oriented architectures (SOA) Deep understanding of databases, caching strategies, and low-latency service design Experience designing clean, scalable APIs with a strong focus on client and end-user experience Experience handling data synchronization from diverse external sources and designing high-consistency data pipelines Comfortable taking ownership in an unfamiliar or legacy codebase and incrementally refactoring and improving it Strong inclination toward automation and reducing manual operational toil Experience with Spark or big data processing is a plus Strong communication skills with the ability to act as a true partner to Product — challenging requirements and driving roadmap decisions

About Backstory.ai:

Backstory helps companies understand the state of their revenue business by answering questions that span customer interactions, sales activity, pipeline health, and deal execution. The platform operates over trillions of sales activities, millions of deals, and more than 160 million business contacts, giving customers a unified view of the signals that drive revenue. Companies such as Nvidia, OpenAI, AMD, Red Hat, and Databricks rely on Backstory to surface risks, identify opportunities, and understand what's happening across their business. Backstory is building AI systems that reason over massive amounts of enterprise data to help business leaders understand what's happening in their business and what to do next. We work at the intersection of large language models, retrieval, evaluation, distributed data systems, and product design, turning billions of signals from across the enterprise into insights people can trust. The underlying challenges span reasoning, search, ranking, data quality, knowledge representation, and operating AI systems against continuously evolving real-world information. We value ownership highly — the ability to take an idea through all the stages from conception to shipping a product. This reflects throughout our company, but is especially true in engineering. As an engineer at Backstory, you'll be a part of a highly independent and autonomous team. Since we're building out a robust data layer that needs to be presented elegantly to the end-user, you'll be working with a large array of different technologies and fields. Expect lots of interesting challenges. Headquartered in San Francisco, CA, Backstory is backed by Y Combinator and Silicon Valley’s top investors, including ICONIQ Capital, Andreessen Horowitz, Lightspeed Venture Partners, Akkadian Ventures, and Mubadala Capital. Backstory is listed in the top 20 percent of Inc 5000 companies, is a regular leader in our key categories on G2, and is on the Forbes list of America’s Best Startup Employers. For more information, please visit www.backstory.ai.