Senior Elixir Engineer - Remote & Real-Time Platform Expert

Hack The Box; Polska; Remote; PLN 392,000 - 654,000; Full time

Benefits offered by this job

25 annual leave days

Parental leave

Home Office Allowance

Training and conference budget

State-of-the-art equipment

Access to Hack The Box lab offerings

Flexible working hours

Job summary

Hack The Box seeks a Senior Elixir Engineer to own backend and full-stack feature delivery on Phoenix and LiveView. You’ll design resilient OTP systems, clean APIs, and real-time experiences that scale to millions of users.

You’ll collaborate with product, design, and security researchers, mentoring engineers and shaping our technical roadmap in a remote-first environment across Europe, with relocation support to Athens if desired.

Qualifications

• 5+ years of backend or full-stack development, with 3+ years shipping production Elixir/Phoenix.
• Strong grasp of OTP and BEAM — processes, supervision, GenServer/GenStage.
• Hands-on experience with Phoenix LiveView (components, streams, JS hooks).
• Deep Ecto and PostgreSQL knowledge: schema design, query optimization, migrations.
• Experience with background jobs (Oban) and event-driven architectures.
• Solid testing discipline with ExUnit; comfortable with property-based and integration testing.
• Familiarity with containerized deployment (Docker, Kubernetes) and CI/CD.
• Security-minded engineering: OWASP fundamentals, auth patterns, secure data handling.
• Excellent written & verbal communication in remote/async environments.

Responsibilities

• Design and build production Phoenix applications — REST APIs, LiveView UIs, and real-time features on PubSub/Channels.
• Model and evolve data with Ecto and PostgreSQL, writing performant queries and migrations.
• Build fault-tolerant systems with OTP: supervision trees and distributed BEAM patterns.
• Own background processing with Oban and observability via Telemetry.
• Ship secure-by-default code with proper auth patterns and least-privilege access.
• Deploy and operate services on Kubernetes/GCP with CI/CD pipelines.
• Mentor engineers and contribute to technical leadership through code reviews and standards.
• Document decisions and communicate clearly in a remote-first environment.

Skills

Backend development

Elixir / Phoenix

OTP BEAM

Phoenix LiveView

Ecto & PostgreSQL

Oban

Testing with ExUnit

Docker & Kubernetes

CI/CD

Security awareness

Remote collaboration

Tools

Elixir

Erlang

Phoenix

PostgreSQL

Oban

Tailwind CSS

Telemetry

Prometheus

Grafana

Sentry

Docker

Kubernetes

GCP

Job description

Hack The Box seeks a Senior Elixir Engineer to own backend and full-stack feature delivery on Phoenix and LiveView. You’ll design resilient OTP systems, clean APIs, and real-time experiences that scale to millions of users.

You’ll collaborate with product, design, and security researchers, mentoring engineers and shaping our technical roadmap in a remote-first environment across Europe, with relocation support to Athens if desired.