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Fiverr Pro
English
$
USD
I will build a scalable backend API for your application
John S
About this gig
Need a properly built backend, not just a collection of endpoints?
I am a Senior Backend Engineer specialising in scalable APIs, distributed systems, databases and production backend architecture.
I will design and build a clean, maintainable backend API for your web, mobile, SaaS, fintech or data-driven application.
I can help with:
- REST API design and development
- Java & Spring Boot backend development
- Go or Python backend services
- PostgreSQL and database design
- Authentication and authorization
- Business logic and transactional workflows
- Third-party API integrations and webhooks
- Kafka and event-driven systems
- Docker and deployment
- Performance and scalability
My focus is not simply making an API work. I design around reliability, maintainability, data integrity and how the system will behave in production.
Please message me before ordering for complex systems or existing codebases so I can understand the requirements and recommend the right package or custom offer.
Get to know John S
John S
Senior Backend Engineer
- FromKenya
- Member sinceNov 2018
- Avg. response time1 hour
Languages
English
Senior Backend Engineer specialising in production backend systems, APIs, fintech infrastructure, identity, and enterprise integrations. I work mainly with Java and Spring Boot, with experience in Python, Go, and Node.js/Express. I’ve built financial transaction systems, investment platforms, enterprise SSO, legacy integrations, large-file infrastructure, and API/data platforms using PostgreSQL, Kafka, Keycloak/OIDC, and Docker.
Other Software Development Services I Offer
FAQ
What information do you need before starting?
Please provide your application requirements, expected API functionality, preferred technology, if any, database requirements, existing documentation/codebase, and any external services that need to be integrated.
Which technologies can you work with?
My primary backend stack includes Java/Spring Boot, PostgreSQL and Kafka. I also build backend services and data systems using Go and Python when they are a better fit for the project.
Can you work on an existing backend?
Yes. I can extend, refactor or integrate with an existing backend. Please contact me before ordering so I can review the current architecture and scope the work correctly.
Does the package include deployment?
Deployment is available as an additional service. I can Dockerize the application and deploy it to your provided server or cloud environment. Complex cloud infrastructure, Kubernetes or CI/CD requirements should be discussed separately.
What counts as a revision?
A revision covers reasonable changes to the agreed functionality. New features, additional endpoints, integrations or requirements outside the original scope are additional work and may require a custom offer.
