Staff Fiber Network Engineer

Details

Anthropic’s mission is to create reliable, interpretable, and steerable AI systems. We want AI to be safe and beneficial for our users and for society as a whole. Our team is a quickly growing group of committed researchers, engineers, policy experts, and business leaders working together to build beneficial AI systems.

About the role

Anthropic is building Anternet — a private, global dark-fiber backbone connecting our data centers, cloud regions, and partners. We light our own glass: long-haul and metro DWDM over leased dark fiber and IRU pairs terminating on our own optical line systems and routers.

We're looking for a Staff Fiber Network Engineer to own the physical layer of this network end-to-end. You'll decide where the fiber goes and then make sure it actually shows up, is spliced clean, and tests to spec. This role combines route engineering, vendor management, and field-delivery program management — the connective tissue between capacity needs and a lit span carrying traffic.

You'll define the inventory system, set acceptance standards, and establish the vendor bench. You'll work closely with optical/transport engineers, the backbone routing team, and data center and capacity planning teams.

Responsibilities

• Route engineering and design: plan terrestrial fiber routes between Anternet PoPs and data centers; evaluate diversity (SRLG, conduit, ROW, landing-station separation), latency, and OSNR/loss budgets; produce route KMZs, splice diagrams, and as-built documentation
• Fiber acquisition: source and qualify dark fiber, IRU, and wavelength options; run RFPs; compare bids on cost, route quality, diversity, and MTTR; drive contracts to signature with legal and procurement
• Vendor and delivery management: own the build from PO to acceptance; track splicing, lateral construction, building entries, meet-me-room cross-connects, and CLS access; hold vendors to schedule and SLA and serve as escalation for late spans or OTDR failures
• Acceptance and characterization: define and enforce fiber acceptance criteria (OTDR bi-directional, IL/ORL, CD/PMD where relevant); review test results, reject substandard spans, and sign off on handover to the optical team
• Capacity and lifecycle management: maintain the source-of-truth fiber inventory (strands, conduits, splice points, leases, IRU terms and renewals); forecast fiber needs against PoP and capacity roadmap; monitor degradation and quality over time
• Operations: partner with NOC and field-ops on fiber cuts, locates, and repairs; drive root-cause analysis with vendors and feed lessons back into route-diversity decisions

Requirements (Minimum qualifications)

• Experience in OSP/fiber planning or network delivery at a carrier, hyperscaler, dark-fiber provider, or large enterprise backbone
• Demonstrated experience taking long-haul or metro dark-fiber routes from design through acceptance — can read an OTDR trace and engage substantively with vendors on splice quality
• Solid working knowledge of the vendor landscape: who has conduit where, how IRU vs. lease vs. wavelength pricing behaves, and what's negotiable in an MSA
• Proficiency with GIS/KMZ tooling for route design and comfort maintaining structured inventory data
• Sufficient understanding of optical transport (DWDM, amplifier spacing, span loss, CD/PMD) to design fiber that line-system engineers can use
• Ability to serve as the single accountable owner for physical delivery across many concurrent builds

Preferred qualifications

• 8+ years of OSP/fiber planning or network delivery experience
• Experience standing up a fiber program from near-zero — building the inventory system, acceptance standards, and vendor bench from scratch
• Familiarity with permitting, ROW, and make-ready processes in US metro markets
• Scripting or light tooling experience (Python, Go, SQL, or similar) for inventory and reporting workflows
• Comfort with occasional travel for site surveys, CLS/ILA walks, and vendor meetings

Annual Salary

$320,000 - $405,000 USD

Logistics

• Minimum education: Bachelor’s degree or an equivalent combination of education, training, and/or experience
• Required field of study: a field relevant to the role as demonstrated through coursework, training, or professional experience
• Location-based hybrid policy: currently, we expect all staff to be in one of our offices at least 25% of the time. Some roles may require more time in our offices.
• Visa sponsorship: We do sponsor visas and retain an immigration lawyer to help, though sponsorship is not guaranteed for every role/candidate.

How we're different

We work as a single cohesive team on a few large-scale research efforts, value impact over small puzzles, and emphasize collaboration and communication. We host frequent research discussions and value diverse perspectives. Guidance on candidates' AI usage is provided on our site.

Additional notes

We encourage applicants even if they do not meet every qualification. Anthropic is a public benefit corporation headquartered in San Francisco and offers competitive compensation and benefits, optional equity donation matching, generous vacation and parental leave, flexible working hours, and office collaboration space.