s
serhatito

Serhat S

@serhatito

NET Backend Engineer

Turkey
English, Turkish
About me
I am a .NET Backend Engineer specializing in designing multi-tenant platforms with ASP.NET Core, Clean Architecture, and Domain-Driven Design. I have experience building scalable enterprise systems handling real-time access control, CRM workflows, and containerized deployments using Docker Swarm and CI/CD pipelines. I work across the full backend stack, focusing on security, data protection, and observability.... Read more

Skills

s
serhatito
Serhat S
Offline • 
Average response time: 1 hour

See my services

API & Integrations
I will be your dotnet backend developer for apis and web apps
From$50 / projectMore details
Bug Fixes
I will fix bugs and errors in your asp net core and c sharp application
From$30 / projectMore details

Portfolio

Work experience

Tokenbox

.NET Backend Engineer

Tokenbox • Full-time

Nov 2025 - Present • 9 mos

Building multi-tenant SaaS platforms on .NET 10 and ASP.NET Core using Clean Architecture and Domain-Driven Design. Dormimy - subscription-based dormitory management platform. Primary backend developer. Built the financial module (ledger, installment billing, deposits, refunds, collections), student admission and bed placement flows, contract management, and inventory and maintenance tracking. Implemented centralized audit stamping, field-level PII encryption, outbox-pattern domain events, and a code-generated permission matrix. TexPass - physical access control platform authenticating through QR, NFC/DESFire cards, BLE, and face recognition across turnstiles and doors. Worked on multi-tenant licensing, rule-based access zones, visitor and vehicle management, and the Raspberry Pi edge agent handling GPIO relays and secure device provisioning. M2CRM - multi-tenant CRM built on a layered service pattern with PostgreSQL and EF Core. Shared infrastructure - contributed to an internal NuGet ecosystem covering authentication, JWT, key management, caching, notifications, and payment gateway integrations, reused across all company products. Stack: C#/.NET 10, ASP.NET Core, EF Core, PostgreSQL (Citus, pgvector, pg_trgm, PgBouncer), Redis, NATS, SignalR, Docker, GitHub Actions, OpenTelemetry, Grafana, Next.js, React, TypeScript, Tailwind CSS. Focus areas: multi-tenant isolation, RBAC and permission systems, JWT with two-factor authentication, audit logging, GDPR/KVKK-compliant data protection, real-time messaging, and production observability. Strong emphasis on test-driven development with xUnit and Testcontainers, and on security auditing across cross-tenant access, privilege escalation, and race conditions.