Senior Software Engineer (python, infrastructure)

Sauce Labs, Inc.; Warszawa; Hybrid; PLN 220,000 - 360,000; Full time

Job summary

Sauce Labs, Inc. in Warsaw, Poland seeks a Senior Software Engineer to span the stack of a distributed system. You will enhance observability, improve delivery cadence, and design services across device lifecycle—from boot to teardown—on Kubernetes or bare-metal environments.

Join a team focused on macOS internals, with collaboration across Product, Test Orchestration, and Cloud teams. Strong coding and DevOps experience required, including Go and Python in CI/CD.

Qualifications

• Design, build and operate distributed systems in production.
• Experience with Kubernetes and fleet orchestration (Agones or similar).
• Proven ability to ship production code in Go and/or Python via CI/CD.
• Strong observability skills: metrics, logs, traces, visibility.
• Hands-on DevOps and Linux/Unix experience: diagnose and fix issues on machines.
• Track record of shipping through code reviews and pairing.
• Familiarity with macOS tooling (simctl, launchd, XPC).
• Experience building OS or VM images with Packer, tart, Ansible.

Responsibilities

• Lead by example: set testing and observability standards.
• Own the device lifecycle services across the fleet and images.
• Improve fleet observability across delivery and image build pipelines.
• Root-cause and fix lifecycle regressions with tests and automated checks.
• Reduce boot and teardown times; optimize image footprint.
• Collaborate with Cloud and Test Orchestration to land changes.

Skills

Distributed systems

Go

Python

Observability

DevOps/Linux

Code review & pairing

macOS internals

System design

Startup experience

Swift

Tools

Kubernetes

Agones

CI/CD pipelines

Go tooling

Python tooling

Packer

Ansible

cloud-init

sysprep

Job description

Senior Software Engineer (python, infrastructure)

Warsaw, Poland

The Role:

This is not a narrow specialist role. We need someone who can move across the whole stack of a distributed system: understand how the pieces fit together, make the system observable enough that we know what's working and can diagnose what isn't, write and structure code with clear boundaries and the right things encapsulated, and be just as comfortable SSHing into a fleet machine to dig into a live problem as designing the system on a whiteboard.

You'll join the Virtual Device Cloud team, which has deep, concentrated strength in macOS, CoreSimulator and APFS internals, and work closely with the Product Manager and with the Test Orchestration and Cloud teams. Your job is to improve testing discipline and cross-platform observability, and to raise delivery cadence, correctness, and visibility across the fleet.

Responsibilities:

• Lead by example - set the team’s standard for testing, observability and delivery through code review and pairing, and bring others along.
• Own the device lifecycle - design and build the services this team owns across the whole device lifecycle, from the image a device boots to its teardown. That covers readiness, session lifecycle and the fleet definitions that plug simulators and VMs into our orchestration layer, whether the fleet runs as pods on Kubernetes with Agones or as VMs on bare-metal and cloud hosts.
• Make the fleet observable - build and use the observability tooling that answers "is it working as intended, and if not, why not" across the fleet and the image build pipeline, including guests and VMs that fail silently before their payload even starts.
• Fix lifecycle problems for good - root‑cause and fix recurring lifecycle regressions with tests and automated release checks, so the same bug does not ship twice.
• Make devices boot and recycle faster - measure and reduce boot, ready and teardown time end to end, and put image and side‑disk footprint on a budget.
• Work across teams - work with the Cloud and Test Orchestration teams to propose and land evidence‑backed changes to systems you do not own. Keep the contracts between our layers explicit.

Required Skills:

• Solid experience designing, building, and operating distributed systems in production.
• Hands‑on experience with Kubernetes, ideally including fleet orchestration such as Agones or a comparable session‑fleet model.
• Proven ability to ship production code in Go and/or Python through a standard CI/CD deployment path, including building and maintaining the pipelines themselves.
• Strong observability instincts and experience: metrics, logging, tracing, and building visibility into systems that don't have it yet.
• Hands‑on DevOps and Linux/Unix systems experience: able to log into a machine (VM, container host, or bare metal) and work confidently - diagnosing, fixing, and understanding what's actually happening on the box.
• Delivers through the team: a track record of shipping via review and pairing on systems others operate, not alone.
• macOS literacy: simctl, launchd, XPC, and how Apple's virtualization/simulator stack fits together.
• Storage and copy‑on‑write design knowledge (e.g. APFS or similar filesystem internals).
• Working experience across Windows and Linux infrastructure.
• Familiarity with the Apple Virtualization Framework and related tooling (e.g. tart).
• Has owned a startup, boot or ready‑time number for VMs, containers, CI runners or game servers and driven it down.
• Swift: some of our repositories use it, and reviewing them is part of the role.
• Experience building and maintaining OS or VM images with tools such as Packer, tart, Ansible, cloud‑init or sysprep.

We are a hybrid workplace that recognizes the importance of flexibility while valuing in‑person collaboration and relationship building. As a result, Saucers located near an office location must be able and willing to come into the office. Those hired remotely must be able and willing to travel to an office as required by the specific role.

Sauce Labs is proud to be an Equal Opportunity employer and values diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender identity/expression/status, sexual orientation, age, marital status, veteran status or disability status.

Security responsibilities at Sauce

At Sauce, we will commit to supporting the health and safety of employees and properties, partnering with internal stakeholders to learn and act on ever‑evolving security protocols and procedures. You’ll be expected to fully comply with all policies and procedures related to security at the department and org wide level and exercise a ‘security first’ approach to how we design, build & run our products and services.