Application Developer

Role Title: Application Developer Location: Sheffield (3 days onsite is mandatory) Rate: £400 - £475 Role Summary We are looking for a highly skilled Application Developer with strong expertise in identity API…

Pay rate £400 – £475/day
Contract type Contract
Posted 10 September 2026

Trusted. Transparent. Built for contractors. Thousands of UK contractors find their next contract on ContractorUK.

View all IT & technology jobs ›

About this contract

Role Title: Application Developer
Location: Sheffield (3 days onsite is mandatory)
Rate: £400 - £475

Role Summary

We are looking for a highly skilled Application Developer with strong expertise in identity API development, data ingestion and transformation, and event-driven (Pub/Sub) architectures. This role focuses on building secure, scalable identity and access workflows across Google Cloud Platform, integrating identity services with custom APIs, Pub/Sub pipelines, and cloud-native applications.
You will collaborate closely with tech leads, Cloud Security, DevOps, and Application
Engineering teams to design and implement robust IAM automation, identity lifecycle workflows, and secure service integrations that support enterprise-level cloud and Identity operations.

Key Responsibilities

Identity Orchestration
Design and implement identity flows for provisioning, de-provisioning and orchestration of identity lifecycle events.
Integrate with Cloud Identity Services, ServiceNow, and internal services to streamline / orchestrate identity provisioning and identity lifecycle management.
Build policy-based orchestration workflows for adaptive authentication and contextaware access using industry standards (like OPA).

API Development

Design, build, and secure RESTful APIs and backend services supporting identity, provisioning, and governance workflows.
Integrate APIs with our new authentication service for token validation, user sessions, and application-level authorization.
Build and document internal SDKs, middleware, and shared libraries for consistent IAM logic across services.
Ensure API security, performance, reliability, resilience, and observability.

API-to-Pub/Sub Event Processing

Develop pipelines where API events publish to Pub/Sub for asynchronous workflows such as:o automated identity lifecycle tasks o access review event triggers o logging and audit forwarding o security anomaly detection

Build Cloud Functions, Cloud Run microservices, or containerized services to process Pub/Sub messages.
Implement robust event-processing patterns including retries, idempotency, DLQs, and structured logging.

Automation & Infrastructure as Code

Build and maintain Terraform modules for IAM, API services, Pub/Subtopics, workloads, and permissions.
Automate deployment and validation of identity and access configurations via CI/CD pipelines.
Implement automated testing for IAM policies and API behaviour.

Support, Troubleshooting & Collaboration

Troubleshoot identity, access, and API workflow issues across distributed systems.
Provide technical guidance to engineering teams on secure API design, IAM best practices, and identity workflows.
Work with security teams during audits, compliance checks, and incident investigations.
Required Skills & Experience

Technical Expertise

Proven experience with modern identity orchestration platforms (Auth0 Actions, Okta Workflows, WorkOS, or SlashID)
Strong programming skills in Python, Go, or Node.js for API and microservice development.
Experience designing and deploying cloud-native APIs (Cloud Run, Cloud Functions, GKE).
Deep understanding of event-driven architectures, Pub/Sub, message processing, and workflow automation.
Strong knowledge of OAuth2, OIDC, JWT, SAML, and identity federation patterns.
Proficiency in Terraform or equivalent IaC tools.
Experience using API gateways, reverse proxies, or service mesh technologies.

Soft Skills

Analytical thinker with strong debugging and root-cause analysis abilities.
Clear communication skills with the ability to collaborate across engineering, security, and operations teams.
Ownership mindset, with a security-first mentality and attention to detail.
Ability to work in an agile, fast-paced environment.

Nice-to-Have

Full Stack App Development (React)
Google Professional Cloud Security Engineer or Cloud Architect certification.
Experience with additional identity providers (Okta, Azure AD, Ping Identity).
Familiarity with Kubernetes (GKE RBAC + workload identity).
Experience using Secret Manager, Vault, or other secrets management tools.
Knowledge of compliance frameworks (SOC2, ISO 27001, PCI, HIPAA).

Education

* Bachelor's degree in computer science, Engineering, Information Security, or equivalent hands-on experience.

If you receive suspicious outreach claiming to be from us, please contact us via the ManpowerGroup website

Apply for this job

You'll complete your application on CV-Library, our jobs partner.

← More IT & technology jobs

Set up for this contract

ContractorUK partners
Markel Direct IR35 and contractor insurance

Most agencies and clients ask for professional indemnity and public liability before you start.

Get your quote →
SG Accounting Contractor accountants

Working through your own limited company? A contractor-specialist accountant keeps the admin off your desk.

Find out more → Also: Caroola · Dolan Accountancy · Compare all accountants

Get new IT contracts by email

One email when new matches appear. Unsubscribe with one click.

Prefer to be found? Upload your CV to CV-Library — free