Skip to content
CV Rocket
Get started
How it worksThe enginePricingBlogContactSign in

Open nowPosted 21 days ago

Senior Back End Engineer

Elixirr Digital15 open roles

Where
Rijeka or Zagreb
Get the CV for this job

From $25 per CV, paid once. No subscription.

Your applicationOpen nowSenior Back End EngineerElixirr Digital · Rijeka or Zagreb

  1. YouYes, apply to this one.

  2. CV RocketCV written for this posting.

  3. 25 readersRecruiter, hiring manager, skeptic. Round after round.

  4. CV RocketApplied on Elixirr Digital's own form.

The reply lands in your private mailbox

3×more interviews than doing it yourself with ChatGPT.

The clock on this job

Early applications get read.

11.3% of postings close within 7 days. Measured by our own scanner across the market.

Share of postings closed within
  1. 2.0%1 day
  2. 4.3%3 days
  3. 11.3%7 days
  4. 17.6%14 days
  5. 34.3%30 days
  6. 43.5%60 days
This job: posted 21 days ago

The posting

Elixirr Digital is transforming how consulting services are delivered. This role is critical to designing and implementing the backend infrastructure that powers our AI-driven solutions and internal agent platform.

As a Senior Back End Engineer, you will design and build scalable, production-grade backend services primarily using Python and FastAPI, while integrating AI capabilities into the systems and products we develop.

We’re looking for someone who combines strong backend engineering fundamentals with hands-on experience working with AI in production. You’ll be expected to independently design solutions, make technical decisions, and take ownership from idea through implementation.

This is an engineering role for someone who wants to move fast in a modern, AI-assisted software development lifecycle and actively uses AI development tools to improve the way software is built.

At Elixirr Digital, you’ll have the opportunity to work with advanced technologies, grow alongside a team of talented professionals, and make a lasting impact across diverse industries.

Candidates applying for employment contract kindly note this position is a hybrid working opportunity from our locations in Rijeka or Zagreb.

What you will be doing as a Senior Back End Engineer at Elixirr Digital?

Backend Architecture & Development

  • Design, build, and maintain scalable backend services using Python and FastAPI.
  • Take end-to-end ownership of backend components and features, from solution design and technical decision-making through implementation, testing, and deployment.
  • Build production-grade services with scalability, performance, reliability, and maintainability in mind.
  • Design and integrate APIs, internal systems, and third-party services.
  • Work within our AWS and Azure ecosystem to develop and operate backend solutions.
  • Identify technical trade-offs, propose solutions, and communicate architectural decisions clearly to the wider team.

AI-Enabled Backend Engineering

  • Build and integrate AI and LLM capabilities into production backend systems.
  • Work with AI and agent frameworks to integrate models, agents, and AI-powered services into our platform.
  • Design backend services that support scalable AI inference, streaming, and increasing system throughput.
  • Build integrations between AI tooling, internal data and services, and third-party systems.
  • Contribute to building scalable, reliable, and production-ready AI-enabled systems.
  • Work closely with AI Engineers to bridge strong backend engineering practices with our growing AI ecosystem.

Security & Production Readiness

  • Build backend services with security, reliability, and production readiness in mind from the start.
  • Apply authentication and authorization practices when designing and implementing APIs and backend services.
  • Follow secure coding practices and ensure appropriate protection of sensitive data across services and integrations.
  • Design systems with appropriate logging, monitoring, error handling, and observability to support reliable production operations.
  • Identify potential security risks and contribute to maintaining secure and resilient backend systems.

AI-Assisted Software Development

  • Use modern AI-assisted and agentic development tools such as Codex, Cursor, or similar tools as part of your day-to-day engineering workflow.
  • Use AI tooling to accelerate development while maintaining high standards for code quality, security, and maintainability.
  • Review and validate AI-generated code with the same rigor as traditionally written code.
  • Help continuously improve how AI-assisted development is used across the engineering lifecycle.

Cross-Functional Collaboration & Ownership

  • Work closely with AI Engineers, DevOps, Front End Engineers, Data teams, and other stakeholders to turn complex requirements into production-ready solutions.
  • Contribute to technical discussions and help drive engineering best practices across the team.
  • Take ownership of features and components rather than relying on predefined technical solutions.
  • Collaborate effectively across our international teams.

Competencies and skillset we expect you to have to successfully perform your job

Technical Expertise

  • Strong hands-on experience with Python backend development and FastAPI.
  • Experience designing, building, and operating production-grade backend systems.
  • Experience working with AWS and Azure cloud-native environments.
  • Hands-on experience integrating AI/LLM capabilities into production applications, beyond experimentation or simply consuming AI tools.
  • Experience working with AI or agent frameworks such as LangChain, LangGraph, Google ADK, or similar technologies.
  • Experience designing APIs and integrating internal and third-party services.
  • Strong understanding of scalable backend architectures and experience building systems designed for increasing throughput.
  • Strong understanding of backend security principles, including authentication, authorization, API security, and secure handling of data.
  • Experience with relational and/or NoSQL databases.
  • Demonstrable experience using AI-assisted and agentic development tools, such as Codex, Cursor, or similar tools.

Preferred Qualifications

  • Experience creating, managing, or integrating MCP servers.
  • Experience with AI observability tools, such as LangFuse or similar technologies.
  • Experience with observability in high-scale or AI-enabled production systems.
  • Familiarity with containerization and modern CI/CD practices.
  • Previous experience working in consulting or professional services environments.
  • Experience working in distributed international teams.

Why is Elixirr Digital the right next step for you?

From working with cutting-edge technologies to solving complex challenges for global clients, we make sure your work matters. And while you’re building great things, we’re here to support you.

Compensation & Equity:

  • Individually tailored benefits package
  • Performance bonus
  • Employee Stock Options Grant
  • Employee Share Purchase Plan (ESPP)
  • Competitive compensation

Flexibility & Balance:

  • Flexible working hours and remote work
  • Multi-sport card
  • Full medical checkup

Projects & Tools:

  • Big clients and interesting projects
  • Cutting-edge technologies

Learning & Growth:

  • Learning and development budget
  • Growth and development opportunities

People-Centered Perks:

  • Referral bonus
  • Anniversary bonus

We don’t just offer a job - we create space for you to grow, thrive, and be recognized.

Intrigued? Apply now!

From $25, paid onceGet the CV for this job

What happens when you press

One press. We do the rest.

  1. A CV for this posting

    Written against Elixirr Digital's own wording, from every piece of relevant proof in your profile.

  2. 25 readers review it

    Recruiter, hiring manager, skeptic and more read every draft, round after round. You get the best round.

    The review screen in CV Rocket: how each CV was read, round by round.

  3. We apply on Elixirr Digital's form

    Our application engine gets through the hardest forms there are. Where a question needs you, AI suggests the best answer. Don't want us applying from our IP addresses? Use our Chrome extension: we apply straight from your own browser.

    An application in CV Rocket: every answer filled in on the employer's form.

  4. Every reply, sorted

    Elixirr Digital's answer lands in your private mailbox, and we classify it on arrival: interview, question, rejection.

    The CV Rocket inbox: each employer reply classified as an interview, an action or a rejection.

  5. Reply with AI

    AI helps you write the email, checks it and sends it. We show you whether the recruiter read it.

  6. The interview in your calendar

    Full integration with your calendar. The invitation goes straight in.

    An interview invitation in the CV Rocket inbox, added to the candidate's calendar.
Get the CV for this job

From $25 per CV, paid once. No subscription.

Why it works

3×

more interviews than doing it yourself with ChatGPT.

ChatGPT writes a CV and never learns what happened to it. We see every reply. For each CV we know:

  • How it was written, and how the review scored it
  • When we applied, and how long after the posting went up
  • Which posting, which company, which city
  • Who got the interview, and who heard nothing

That is how we know which CVs get called.

Get the CV for this job

From $25 per CV, paid once. No subscription.

The numbers game

More applications. More interviews.

Every application goes out with its own CV, written for that posting and paid once. Send enough of them and the law of large numbers finds you the job.

Get the CV for this job
By hand5–10
With CV Rocket100
applications a day

Nearby

Live postings like this one

Same employer first, then the same role elsewhere.

Before you press

Straight answers

Get the CV for this job

From $25 per CV, paid once. No subscription.

What if my background isn't good enough?

We make the most of the background you have. The CV uses every piece of relevant proof your profile holds, and one of the 25 readers reads your whole profile and flags what the CV left out.

Do you really apply for me?

Yes, on the employer's own form, the hardest ones included. Where a question needs you, you answer it right there and AI suggests the best answer. Don't want us applying from our IP addresses? Use our Chrome extension: we apply straight from your own browser.

Is it a subscription?

No. You pay once per CV, from $25. Every application goes out with its own CV, written for that posting.

One job. One CV.
Paid once.

Pick the posting you want. We write for it, apply for you and catch the reply.

Get the CV for this job

From $25 per CV, paid once. No subscription.