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English
$
USD
I will architect and build your complex, scalable software platform
John S
About this gig
Building a complex software platform requires more than writing features. It requires the right architecture, data model, system boundaries and engineering decisions from the beginning.
I am a Senior Backend Engineer specialising in scalable backend platforms, distributed systems and production software architecture.
I can architect and build platforms including SaaS products, fintech systems, marketplaces, data platforms and applications with complex business workflows.
Services can include:
- System and software architecture
- Java/Spring Boot, Go, Python or Node.js
- PostgreSQL, Redis and data modelling
- REST APIs and service integrations
- Authentication and authorization
- Complex transactional workflows
- Kafka and event-driven architecture
- Async processing and background workloads
- Performance, reliability and scalability
- Testing and production readiness
Every project is scoped around its actual requirements.
Please contact me before ordering so we can review the product, architecture, scope and delivery plan.
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
Should I contact you before ordering?
Yes. Please contact me before placing an order. Complex software projects require requirements and scope review before development so I can confirm the appropriate package, architecture and delivery plan.
What types of platforms can you build?
I can build backend platforms for SaaS products, fintech systems, marketplaces, mobile/web applications, data platforms, workflow systems and products with complex business logic or integrations.
Can you design the architecture as well as implement it?
Yes. Architecture is part of this service. Depending on scope, this can include system boundaries, data models, API contracts, event flows, integration strategy, reliability considerations and implementation architecture.
Which technology stack do you use?
I work with Java/Spring Boot, Go, Python and Node.js, alongside PostgreSQL, Redis, Kafka, Docker and related backend technologies. Technology choices are based on the system requirements rather than forcing every project into one stack.
What does the $10,000 Premium package include?
Premium is intended for complex platform engineering with multiple domains, workflows, integrations or scalability requirements. It is not unlimited development. Exact functionality and deliverables are agreed before the order begins.
Can you work with an existing platform or codebase?
Yes. I can extend, modernize or build major components for an existing system. I will first need to understand the current architecture, codebase and technical constraints before confirming scope.
What counts as a revision?
A revision covers reasonable changes to delivered work within the agreed requirements. New features, integrations, workflows or architectural changes introduced after scope approval are additional work and may require an extra or custom offer.
Is deployment included?
Production deployment is available as an extra. Complex infrastructure such as Kubernetes, Terraform, multi-region architecture, advanced CI/CD or cloud migration should be scoped separately.
