API Gateway Architect (Apache APISIX)

Purpose

To own the API gateway tier, which serves as the single ingress point for external traffic across the platform. The gateway terminates device trust, enforces authorisation, applies rate-limiting and quota policies, and routes traffic between external consumers and the platform subsystems. Apache APISIX is the selected platform, with Kong retained as a documented fallback.

Key responsibilities

• Define the API gateway architecture: deployment topology, control plane and data plane separation, configuration store, and high-availability posture across the primary and disaster-recovery sites.
• Design the route, upstream, and plugin configuration as versioned code rather than as console or admin API state, so that gateway configuration is packaged and deployed through the same GitOps route as everything else.
• Terminate mutual TLS for field device trust at the gateway, validating device certificates against the device registry, with defined behaviour for unknown, expired or revoked certificates. Designed jointly with the Identity & Security Architect.
• Integrate authorisation enforcement with Keycloak — token validation, introspection strategy, and claim-based routing and access control.
• Define rate-limiting, quota and traffic-shaping policies per consumer class — partner organisations, internal subsystems, field devices and public channels — including behaviour under sustained overload.
• Develop custom plugins where the standard plugin set does not meet platform requirements, and establish the standard for how plugins are written, tested and packaged.
• Define API lifecycle and versioning policy across the platform, including deprecation and the contract with external consumers.
• Integrate gateway telemetry into the platform observability stack — metrics, structured access logging and correlation identifier propagation to upstream services.
• Package the gateway and its configuration as parameterised Helm charts, with externalised configuration, for deployment by the integration team.
• Produce operational runbooks covering routine configuration changes, certificate rotation, incident response and rollback.
• Develop the nominated platform engineer to independent capability.

Essential experience

• Apache APISIX in production at scale, or Kong at an equivalent depth, with demonstrable ability to transfer the reasoning to APISIX.
• Gateway configuration managed declaratively as versioned code, deployed through a pipeline rather than applied by hand.
• Mutual TLS termination at the gateway, with client or device identity validated against an external registry.
• Integration of a gateway with an OpenID Connect provider for authorisation enforcement — token validation, introspection and access decisions at the edge.
• Rate limiting and quota design under real load, with a considered position on behaviour during sustained overload.
• High availability gateway deployment on-premise, including the failover posture and its dependency on the underlying data tier.

Desirable experience

• Custom plugin development for APISIX or Kong (Lua, or WebAssembly-based extension).
• Nginx and OpenResty at a level sufficient to reason about gateway behaviour beneath the abstraction.
• Public sector or regulated API programmes with external partner contracts.
• Field device fleets where device identity was enforced at the edge.

Expected hours: 40.0 – 45.0 per week

Application Question(s):

• Have you delivered software into a multi-party programme, where the organisation deploying it was not the one building it?
• Have you delivered production work in an on-premise or hybrid environment (not cloud-only)?

Experience:

• On-premises: 7 years (Required)

Work Location: In person