Senior Backend Engineer (Telco Integration Lead) Golang in City of London

We are seeking a deeply technical and security-minded Senior Backend Engineer to join a newly-founded, high-impact AI joint venture. Backed by five of the world's leading telecommunications giants, our mission is to restore trust in global voice communication. This is not a standard backend role. We are seeking a foundational engineer to own our single greatest strategic asset: our unique, privileged access to network-level intelligence via the GSMA CAMARA API standard.

You will be the Critical Path Owner for Track Zero, the 30-day foundational sprint to validate and integrate the first-ever CAMARA-based signals (like sim-swap and device-roaming-status) from our telco founders. Your success is the Go/No-Go gate for our MWC 2026 launch. You will be directly responsible for building the out-of-band data path that enables our flagship Telco-Verified Security Shield and its sub-500ms Time-to-Trust metric, our core differentiator that no over-the-top competitor can replicate. This position offers a unique opportunity to define a new category of network-aware security, working directly with the world's leading carriers to turn their network data into a real-time defence against global fraud.

Key Responsibilities

• Own and build the Security Signal Ingestion path, the secure, low-latency, and out-of-band data channel connecting to our founding members' network API gateways.
• Architect and implement a carrier-agnostic, vendor-agnostic connector layer to consume RESTful APIs from a heterogeneous global landscape of telco partners and IMS vendors (e.g., Nokia, Ericsson, Mavenir).
• Serve as the primary technical liaison to the engineering teams at our telco founders (Deutsche Telekom, Singtel, SKT, etc.), working hand-in-glove to navigate, validate, and productionize their new CAMARA network APIs.
• Design and build the high-throughput microservices that will query, ingest, normalize, and cache network signals (e.g., sim-swap, device-roaming-status) to be used in our real-time Scam_Score model.
• Implement a mandatory Zero Trust security model for this critical integration, our most sensitive asset. This includes mTLS, least-privilege IAM, and network micro-segmentation.
• Serve as the Critical Path Owner for Track Zero, our 30-day sprint to validate and integrate real-time signals from at least two telco partners, culminating in a Go/No-Go demo.
• Ensure all network API integrations meet the stringent P99 latency budgets.
• Collaborate with the platform team to build a parallel development path using mocked data to mitigate risks of network API delays.
• Define and own the data contracts and pipelines that feed this "ground-truth" network data from the integration layer to our core AI Service Bus (Apache Kafka).
• Work closely with the Scam Detection Service and AI/ML teams to define the feature vectors and data payloads needed from the network to power our proprietary machine learning models.
• Partner with product and leadership to define the Phase 2 (post-MWC) roadmap for co-developing new, proprietary network APIs (like Caller_Velocity from CDRs) that will become our long-term, indefensible moat.
• Document integration architectures, data schemas, and security controls to create setup guides for our Founding Member partners.
• Collaborate with our external InfoSec vendor to ensure the integration layer is continuously validated and hardened against threats.

Required Qualifications

• Bachelor's degree in Computer Science, Engineering, or a related field.
• 7 years of hands-on experience in backend engineering, with a proven track record of building and maintaining high-performance, distributed systems in production.

Required Technical Skills

• A minimum of 5 years of production experience with Go (Golang). Experience in other languages (e.g., Python, Node.js) is valued, but will not replace this core Go requirement.
• Strong, demonstrable experience with real-time, low-latency data processing. You obsess over milliseconds and understand the trade-offs.
• Proficiency with cloud platforms (AWS, GCP, or Azure) and containerization technologies (Kubernetes, Docker).
• Deep understanding of API design (REST, gRPC, Webhooks) and API security (OAuth 2.0, mTLS, JWTs).
• Knowledge of (or deep, demonstrable curiosity about) telecommunications protocols and architectures. You must be comfortable talking to network engineers.
• Experience with high-throughput messaging or streaming platforms (e.g., Kafka, Pulsar).

This is a permanent position with hybrid working of two days a week in the central London office and the rest WFH. The salary is very much dependent on experience with a guide between £110k-£140K basic package.