Open to full-stack engineering roles
Liyona Johny
Full-Stack Software Engineer
I build the API and the interface that sits on top of it, then ship the whole thing.
Full-stack software engineer with over five years of experience building web applications and platforms, from REST API design in Python and Java through to production front ends. I currently build custom business applications, a learning platform, and high-performance websites for a US web studio. Before that I owned both the FastAPI backend and the React front end of an enterprise digital twin platform, including authentication, security, testing, and AWS deployment.
FastAPI + React
- Years of engineering experience
- 5+
- Platforms delivered end to end
- 4
- Gain in system stability at Infosys
- 20%
- Endpoints documented in OpenAPI
- 100%
How I work
Four things you can check rather than take on trust
Every claim on this page is one you can verify, either in the code I hand over or in this site itself.
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Security is part of the build
JWT authentication, role-based access, audit logging, and CORS policy across both API and UI, not bolted on afterwards.
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Tested before it ships
PyTest and JUnit coverage, peer review, and front-end behaviour verified against the API contract before release.
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Documented for handover
Every endpoint in OpenAPI, and system behaviour written up in language non-engineers can use without me in the room.
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No tracking on this site
No analytics, no cookies, no third-party scripts. The contact form is the only thing that ever sends data anywhere.
What I do
The whole stack, not half of it
I work across the whole stack. On the backend that usually means Python with FastAPI or Django, SQLAlchemy and Pydantic for modelling and validation, and PostgreSQL or MySQL underneath. On the front end it means React with hooks and context, or Astro when a site has to be fast and search friendly above everything else.
Most of my work starts with an open-ended conversation rather than a written spec. I'm comfortable sitting with clients and researchers who are not engineers, turning what they describe into a data model, an API surface, and an interface they can actually use, then documenting it in language they can rely on long after handover.
I use AI coding tools every day, and I review and test what they produce to exactly the same standard as code I write by hand.
More about how I work-
API design that holds up
Typed request and response models, validation on ingest, and every endpoint documented in OpenAPI so the people consuming it never have to guess.
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Front ends that match the contract
Component architecture and state management in React, with behaviour verified against the API contract before anything reaches release.
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Security built in, not bolted on
JWT authentication, role-based access control, protected routes, session handling, audit logging, and CORS policy across both API and UI.
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Performance as a requirement
Core Web Vitals budgets, technical SEO, structured data, and accessibility treated as acceptance criteria rather than a later clean-up pass.
Selected work
Three builds worth reading about
Each of these has a full write-up covering the problem, the constraints, the decisions, and what I would change.
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Digital Twin Platform
2023 to 2025
Santane Ltd
Real-time simulation and analytics platform managing live data streams, validating every input on ingest and delivering processed output to the interface.
- FastAPI services and React interfaces that visualize live twin data.
- JWT authentication and role-based access control across both API and UI.
- AWS environments provisioned and operated with Docker, Git, and Jenkins pipelines.
Read the case study
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ClinicalPilot AI
2025 to 2026
AI-powered clinical research platform, MCA major project
A research platform that takes messy clinical datasets and turns them into something a researcher can question directly.
- Automated dataset validation and cleaning before anything reaches analysis.
- AI-assisted paper summarisation and dataset question answering on a retrieval pipeline.
- Interactive dashboards for cohort discovery.
Read the case study
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Freelance client build
A scheduling and administration application for a music school, with family accounts and a moderated messaging layer.
- Scheduling, family accounts, and moderated messaging between staff and families.
- Role-based access with audit logging on sensitive actions.
- Single sign-on into LearnDash so students move between systems without a second login.
Read the case study
Writing
Notes from the work
Practical guides on API design, security, performance, and testing. Written from things I have actually had to get right.
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The PyTest fixtures worth writing on day one
Four fixtures that make an API test suite fast, isolated, and pleasant to add to, with the database rollback pattern in full.
Read it
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Single sign-on between a custom app and a WordPress LMS
How to let one login carry a user into LearnDash without making WordPress the source of truth, and the mistakes to avoid on the way.
Read it
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Designing a REST API other people can actually use
Naming, status codes, errors, pagination, and versioning decisions that save your consumers from guessing.
Read it
Next step
Looking for someone to own this end to end?
I am open to full-stack engineering roles and to contract builds. Tell me what you are trying to solve and I will tell you honestly whether I am the right person for it.
- Replies: Within two working days
- Based in: the United States
- Open to: full time, contract, remote or hybrid