Leo Johnston Mesia
Software engineer from England. I build full-stack systems, break things on purpose, and write too much documentation. Half Peruvian, bilingual in English and Spanish. Currently finishing A-Levels and building things that probably shouldn't work but do.
Building something new
AboutWhat I do
End-to-end systems — database schemas, REST APIs, React frontends, deployment pipelines. I think in architectures, not just features.
Bilingual
Native English & Spanish
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Essex, England
Nothing right now
1,391
GitHub contributions
this year
Suggest me a song
shared playlist ↗Think I'd vibe to something? Drop a recommendation and I'll check it out.
Work
Workforce Management & Pay Tracking
A-Level CS NEA. Full HR & scheduling system for SMBs — employee scheduling, attendance, role-based access, payroll. 100k+ word write-up.
# Schedule creation with conflict detection
@router.post("/shifts")
async def create_shift(
shift: ShiftCreate,
db: AsyncSession = Depends(get_db)
):
await validate_no_overlap(db, shift)
result = await shift_service.create(db, shift)
return {"id": result.id, "status": "confirmed"}
WebScene
TypeScript Canvas video composition engine. After Effects-style timeline with layers, tracks, keyframes. Deterministic rendering and frame export.
const scene = new Scene({ width: 1920, height: 1080 });
const layer = scene.addLayer("main");
layer.addKeyframe({
time: 0,
opacity: 0,
transform: { scale: 0.8 }
});
await scene.render();
JRNI Demo
Booking system API integration built during work experience at bookinglab. React frontend consuming the JRNI scheduling API.
Cascade
SaaS hosting platform replacing the WHMCS/Pterodactyl/cPanel stack. Zero-trust architecture with mTLS, signed actions, and data sovereignty. Native LXC, KVM, and Docker workloads.
PteroDev — sunsetted
Addon and theme developer for the Pterodactyl open-source game server panel — both paid and free releases, extending the platform for the wider community.
Experience
2025Founder of Aftora.ioRemote
2025CTO & Shop Assistant at PicaNutHybrid
2024Work Experience at bookinglabRemote
2024Work Experience at MicrosoftReading & London
PlacesContact
Got a project, an idea, or just want to say hello.