Network Architect

The Opportunity Fossefall is building multi-datacenter AI infrastructure where connectivity sits on the critical path for every site: transit and peering, fiber routes into the buildings, datacenter fabrics and the high-performance networks our GPU clusters depend on. We are looking for a Network Architect to own our network architecture end to end, from the first fiber pair into a building to the last switch port in a rack. You will make sure our datacenters get connected and stay connected. Decisions that are expensive to reverse, such as routing policy, fiber routes, meet-me room layout and fabric topology, will be made early and on our terms rather than left to vendors and contractors. This is the first hire into the network function. You will set the technical standards and the automation baseline that the network team will be built on, so that bringing a new site online becomes a repeatable template rather than a new project. What You'll Do

• Own Fossefall's network architecture end to end across current and future sites, including the WAN and backbone between sites, edge and peering, datacenter fabrics and out-of-band management.
• Take new datacenters online, from ISP-side infrastructure such as transit, peering, IP space, ASN and routing policy through to first production traffic.
• Represent the network in site planning, settling fiber routes, diversity, meet-me rooms, cable plant and physical topology with site and facilities teams before construction locks them in.
• Act as the principal technical contact for fiber providers, carriers, IXPs and hardware vendors, covering technical scoping, negotiation of technical terms and follow-up on delivery.
• Design high-radix, non-blocking, RDMA-capable networks for our GPU clusters, using InfiniBand or RoCEv2 over Ethernet, together with the storage and management networks around them.
• Build the network as code from day one, with a source of truth, configuration generation, CI for network changes and streaming telemetry, so each new site becomes a template rather than a project.
• Work closely with compute and platform teams on fabric, storage and management network requirements, as well as with security on segmentation, firewalling and edge filtering.
• Partner with the Hardware Architect to define hardware platform strategy, ensuring that compute, storage, networking, and physical infrastructure are designed as a cohesive, scalable, and high-performance system.
• Give the executive team, procurement and finance clear input on connectivity cost, risk and timelines, including carrier and vendor contracts and capex for network hardware and circuits.
• Keep up to date with emerging network technologies and trends, making sure current and planned installations are built to meet future demands.
• Establish the technical standards for the network domain, define what the network team should look like and hire into it as Fossefall grows.

About You You bring solid, hands-on experience designing and operating production networks at datacenter or ISP scale. You have brought a new site or POP online, from fiber and cross-connects through to production traffic. You have strong opinions about network design and can explain the trade-offs behind them. You are equally at home in a design document, a terminal or a meet-me room with a torch. You are pragmatic and know the difference between what is textbook-correct and what will actually run reliably with a small team. We believe you will bring:

• Hands-on routing and switching experience, including BGP in the fabric (for example EVPN/VXLAN), IS-IS or OSPF, MPLS or segment routing and IPv6.
• Experience with ISP-side infrastructure such as transit and peering, IXP presence, RPKI and IP/ASN administration.
• Layer 1 fluency: fiber types, optics, cable plant and the physical realities of getting connectivity into a building.
• Practical experience with network automation, for example using Ansible or similar tools.
• The ability to explain designs and trade-offs clearly to site engineers, executives and partners, as well as to hold your own in a commercial conversation with a carrier.
• The confidence to set technical standards that other engineers will follow and the desire to build from the ground up, including the ambiguity that comes with it.
• Clear communication skills in English. Nordic language skills are a bonus.

Experience in one or more of the following areas would be valuable:

• AI or HPC fabrics at GPU-cluster scale, using InfiniBand or RoCEv2.
• NVIDIA networking technologies such as ConnectX, BlueField or Spectrum-X.
• Running a network automation toolchain in production, including source of truth, CI and telemetry.
• Open or disaggregated network operating systems such as Cumulus, alongside the traditional vendors.
• The Nordic connectivity landscape, including relationships with carriers, dark fiber providers and IXPs in the region.
• Hyperscale or neocloud GPU deployments.
• Working as a first or early hire and helping build a new team.

We do not expect one person to have worked with every technology listed or to know everything from day one. What matters most is a strong foundation in datacenter or ISP-scale networking, credible hands-on experience and the judgement to get to grips with unfamiliar technologies quickly. What Success Looks Like Within the first months, Fossefall has a clear and accountable owner for its network architecture across all sites. Connectivity for the first site is delivered on a clear plan, with transit, peering, IP space, ASN and routing policy in place. Network requirements for fiber routes, diversity, meet-me rooms and cable plant were settled with site teams before construction locked them in. The network is built as code, with a source of truth, configuration generation, CI and telemetry in daily use, so the next site is a template exercise rather than a new project. Connectivity partners are held to clear technical requirements and delivery commitments. Colleagues across site and facilities, compute, security, procurement and the executive team understand when and how to involve the role. The technical standards for the network domain are in place and there is a clear plan for the network team and its first hires. Why Fossefall? Fossefall is building for long-term growth, which means many important ways of working are still being shaped. Joining now means having the opportunity to influence how the organization grows, how teams collaborate and how high-quality work gets done. You will work close to capable colleagues, contribute to meaningful priorities and help build something that can last. About Fossefall Fossefall is a Nordic AI infrastructure company founded in 2025. We develop and operate AI factories powered by renewable energy, turning clean Nordic power into scalable, sovereign computing capacity for Europe, built in partnership with local communities, energy producers and technology leaders across the world. As a team, we are still small enough to know each other as people, and our culture is shaped by ownership, curiosity, warmth and collaboration. Interested? Make sure your CV is up to date for this role. Rather than a cover letter, we would like you to write a short note about a network you have designed or brought online, including what you would do differently today. We review applications as they come in and keep the role open until we find the right colleague. Due to the nature of our business, background checks and/or security clearance may be required as part of the employment process.