Senior Optical Network Engineer II

coreweaveu; Warszawa; On-site; PLN 300,000 - 520,000; Full time

Benefits offered by this job

Living Wage accreditation

Job summary

CoreWeave is seeking a senior Optical Network Engineer to design, build, and operate the global optical backbone. You will work across dark fiber, DWDM, amplification, spectrum planning, and coherent transmission, collaborating with IP Backbone Engineering to ensure capacity, diversity, and resiliency.

The role requires hands-on deployment and production operations with platforms from Nokia and Ciena, and you will mentor peers to raise engineering standards.

Qualifications

• Strong hands-on experience with production optical networks involving Ciena and Nokia platforms.
• Experience deploying and operating dark-fiber networks and DWDM systems.
• Ability to design optical paths, wavelength planning, and power budgets.
• Experience with coherent optical transmission, ROADMs, 400G/800G technologies.

Responsibilities

• Design, build, and operate CoreWeave's global optical backbone.
• Engineer DWDM systems across dark-fiber infrastructure.
• Deploy, configure, and troubleshoot Nokia and Ciena platforms.
• Plan and execute network capacity expansions and new fiber spans.
• Mentor engineers and help establish technical standards and culture.

Skills

Ciena platforms

Nokia platforms

DWDM

Dark-fiber expertise

Fiber characterization

Coherent transmission

OSNR/ESNR understanding

Incident response

Tools

OTDR

Amplification knowledge (EDFA/Raman)

Job description

CoreWeave is The Essential Cloud for AI™. Built for pioneers by pioneers, CoreWeave delivers a platform of technology, tools, and teams that enables innovators to build and scale AI with confidence. Trusted by leading AI labs, startups, and global enterprises, CoreWeave combines superior infrastructure performance with deep technical expertise to accelerate breakthroughs and turn compute into capability. Founded in 2017, CoreWeave became a publicly traded company (Nasdaq: CRWV) in March 2025. Learn more at www.coreweave.com .

We're proud to be a Living Wage accredited Employer.

What You'll Do:

We are building a global optical backbone designed to support infrastructure at massive scale. We are looking for experienced Optical Network Engineers to help design, build, operate, and evolve the optical network that underpins our global IP backbone.

This is a senior engineering role for engineers with deep, hands-on experience designing and operating production optical networks. You will work across the complete optical lifecycle, from dark fiber and photonic engineering through DWDM system design, deployment, capacity expansion, automation, monitoring, and production operations.

You will work closely with IP Backbone Engineering and Network Architecture to ensure that the optical and IP layers are designed together to provide predictable capacity, physical diversity, failure isolation, and resiliency.

We are specifically looking for engineers who understand the underlying optical network, not just how to configure individual platforms.

About the role:

You will help design, build, and operate our global optical backbone.

Design, engineer and operate long-haul, metro, and data-center interconnect optical networks.

Engineer DWDM systems across dark-fiber infrastructure.

Design optical paths including amplification, regeneration, wavelength planning, spectrum allocation, and optical power budgets.

Engineer and operate C-band and L-band optical systems.

Deploy, configure, operate, and troubleshoot Nokia, Ciena and other optical platforms.

Commission new fiber spans, wavelengths, and optical systems.

Perform fiber characterization and validate new dark-fiber routes before production deployment.

Analyze span loss, connector loss, reflectance, dispersion, OSNR, Q-factor/Q-margin, BER, and other optical performance characteristics.

Troubleshoot complex optical impairments and fiber-related issues using platform telemetry and appropriate optical test equipment.

Design amplifier chains and understand EDFA and Raman amplification requirements.

Engineer coherent optical transmission across metro and long-haul networks.

Plan and execute network capacity expansions.

Develop standards for optical network architecture, deployment, commissioning, and operations.

Build monitoring and telemetry that identifies optical degradation before it becomes a production-impacting failure.

Participate in incident response and root-cause analysis for optical network events.

Work directly with dark-fiber providers, carriers, data-center operators, and equipment vendors.

Evaluate and qualify new optical platforms, coherent optics, and photonic technologies.

Develop automation and tooling that allows the optical network to scale without equivalent growth in manual operational work.

Mentor other engineers and help establish the technical standards and engineering culture of a new optical networking team.

Who You Are:

This is a senior-level position. Candidates should have significant hands-on experience designing, deploying, and operating large-scale production optical networks.

Required Experience

• Strong hands-on experience with both Ciena and Nokia optical networking platforms.
• Experience should include production deployment, configuration, troubleshooting, software lifecycle, hardware troubleshooting, and operational support-not simply exposure to the platforms.
• Strong experience with dark-fiber networks, including:
• Fiber characterization and acceptance testing.
• Optical loss budgets.
• ILA site design.
• OTDR testing and interpretation.
• Connector and splice loss.
• Reflectance and ORL.
• Chromatic dispersion.
• Polarization-related impairments.
• Fiber types and characteristics.
• Physical route diversity and shared-risk analysis.
• Troubleshooting degraded and failed fiber spans.
• Deep understanding of DWDM and optical transmission technologies, including:
• Coherent optical transmission.
• C-band and L-band systems.
• ROADMs.
• EDFAs and Raman amplification.
• Coherent pluggable optics.
• 400G and 800G optical transmission.
• ZR and ZR+ technologies.
• FEC and pre-/post-FEC performance.
• OSNR and ESNR.
• Q-factor and Q-margin.
• Chromatic dispersion.
• PMD and PDL.
• Optical power management.
• Wavelength and spectrum planning.
• Amplification and regeneration.
• Alien wavelengths and multi-vendor optical environments.

You should be comfortable taking a proposed dark-fiber route and determining how to turn it into a pr