Backend Engineer

Cernel; Aarhus; On-site; DKK 600,000 - 900,000; Full time

Job summary

Cernel is building the next generation of ecommerce infrastructure with AI-powered agents. This Backend Engineer role in Aarhus focuses on scalable core services, APIs, and data-processing pipelines that enable autonomous optimization across shops.

You will work at the intersection of event-driven architectures and real-time data processing, collaborating with the CTO and the broader engineering team to deliver reliable systems for global scale.

Qualifications

• 3+ years of professional backend development experience.
• Solid experience with Golang and Python.
• Exposure to or interest in event-driven architectures.
• Onsite work in Aarhus, remote not accepted.
• Working knowledge of distributed systems, databases, and API design.

Responsibilities

• Build and maintain core platform services (APIs, authentication, billing interfaces).
• Develop and optimize event-driven data ingestion and processing pipelines.
• Collaborate with AI/Product teams to translate requirements into reliable backend systems.
• Ensure code quality with tests and design patterns.

Skills

Golang

Python

Event-driven architecture

Distributed systems

API design

Tools

Protobuf/gRPC

OpenAPI

Google Cloud Platform

Job description

We're hiring a Backend Engineer to join our team in Aarhus

Build the infrastructure powering the AI revolution in ecommerce

We're looking for a backend engineer with a few years of experience who wants to grow while building systems that operate at scale. You'll work alongside experienced engineers on the core infrastructure that enables AI agents to autonomously optimize ecommerce operations for our customers.

You'll work at the intersection of event-driven architecture, AI agents, and real-time data processing, contributing to systems that ingest, analyze, and act on massive amounts of ecommerce data. This is a role for someone who is curious about systems, cares about code quality, and wants to develop their craft alongside a strong technical team.

Join us on our growth journey

At Cernel, we're bringing the AI revolution to ecommerce by building the intelligent backbone behind every item sold online. We make ecommerce teams work smarter, faster, and with amplified abilities across the entire value chain - starting with what lies at the core: product data.

Our infrastructure continuously monitors and acts upon large amounts of data to drive value for ecommerce shops. We ingest customer data, process it, analyze it, and use algorithms to provide and execute optimizations autonomously on webshops.

As Backend Engineer, you'll report to our CTO and work closely with the broader engineering team, contributing to technical decisions and helping build the platform that enables us to scale globally.

Responsibilities and daily work

Platform development

• Build and maintain core platform services (APIs, OAuth, billing services, integration layers)
• Contribute to event-driven systems that handle large-scale data ingestion and processing
• Develop integration and data ingestion APIs that enable seamless customer onboarding
• Participate in architectural discussions and translate decisions into working code

Code quality

• Follow and help refine our development guidelines and code quality standards
• Write end-to-end tests and apply testable design patterns
• Implement well-defined abstractions and system interaction patterns across domains
• Collaborate with the team on technical best practices

Feature development and optimization

• Build features that unlock automation potential for customers
• Optimize performance and reliability of existing systems
• Support AI development teams with reliable infrastructure and tooling
• Collaborate with Product and AI teams to translate requirements into working solutions

Technology stack

• Work with and contribute to our evolving tech stack
• Stay curious about new technologies that could improve our capabilities
• Build systems that support our AI agents' autonomous decision-making
• Help ensure infrastructure reliability and observability

Technologies you'll work with

You’ll have the opportunity to work with cutting‑edge technologies in a modern stack:

• Event‑driven architecture for real‑time data processing
• SQL databases for complex relationship modeling
• Temporal for workflow orchestration
• Protobuf/gRPC and OpenAPI for API development
• Google Cloud Platform for infrastructure
• Golang and Python as primary languages
• Most AI providers currently available

Who you are and requirements

You have:

• 3+ years of professional backend development experience
• A flair for AI‑driven development
• Work onsite in Aarhus (remote not accepted)
• Solid experience with Golang, Python or similar languages
• Exposure to or interest in event‑driven architectures
• Experience building reliable backend systems
• Working knowledge of distributed systems, databases, and API design
• Familiarity with test‑driven development and a desire to write high‑quality code

Who we are

Cernel is building the next generation of ecommerce infrastructure with AI‑powered agents that automate complex tasks and connect workflows across systems. We’re developing an advanced agent framework that analyses data, makes decisions, and drives performance – giving ecommerce teams better results, higher conversions, and more time for creative work.

We are currently a team of 24 people working from our brand new HQ at Frederiksbjerg, Aarhus. We are ambitious, caring, and collaborative. We work hard, move fast, and genuinely care about building both a great product and a great organisation.

We value honesty, data‑driven decisions, and ownership. Our team is collaborative and thrives on open communication. You’ll have the responsibility and autonomy that comes with working in a startup, contributing to the system that enables Cernel’s mission.

Next steps and how to apply

The process for the role will look as follows:

1. Apply and share information about yourself
2. Complete personality assessment
3. 60 minutes onsite interview w/ CTO and CEO
4. 80 minutes technical interview w/ CTO
5. Meet the team and culture fit conversation

Start date: As soon as possible