Back-end engineering
Service architecture and API design in .NET Core and NestJS/TypeScript, with data modelling and performance work on SQL Server and PostgreSQL.
Top Rated Plus
Upwork status
100%
Job success score
4.9/5
across 43 reviews
51
Projects completed
1.100+
Hours worked
12+
Years in software
Freelance track record — Upwork profile
BIOGRAPHY
A founder who still writes the code
Gökhan Eryiğit was born on 20 May 1983 in Eskişehir, Türkiye. He studied management information systems and computer programming, and worked as a senior developer in the refrigeration systems and intelligent transport/IT sectors.
Alongside this he served for fifteen years as a non-commissioned officer. He then resigned to focus entirely on his own projects and his company, bringing the discipline, planning and sense of responsibility of that period with him.
In 2021 he founded Peaker Soft as two sister companies: Peaker Soft LLC in Delaware and Peaker Soft Yazılım San. Tic. Ltd. Şti. in Diyarbakır, within the Dicle Teknokent technology park. The company began with conventional software and web development, and shifted its focus to artificial intelligence as large language models matured. Today its core expertise is RAG pipelines, self-hosted model inference, LoRA/QLoRA fine-tuning and AI agent development.
Alongside corporate projects he works directly with international clients. He holds Top Rated Plus status on Upwork, with 51 completed projects, over 1,100 hours worked and a 100% job success score, rated 4.9/5 across 43 reviews.
ROLE
Founder · AI & Back-end Engineer
COMPANIES
Peaker Soft LLC
Delaware, USA — founded 2021
Peaker Soft Yazılım San. Tic. Ltd. Şti.
Diyarbakır, Türkiye — founded 2021
BASED IN
Dicle Teknokent, Diyarbakır · Newark, DE, USA
LANGUAGES
Turkish, English
STACK
.NET Core
C#
NestJS
TypeScript
SQL Server
PostgreSQL
Ollama
vLLM
LoRA / QLoRA
RAG
n8n
Docker
AREAS OF EXPERTISE
What he works on hands-on
LLM fine-tuning
Parameter-efficient training with LoRA and QLoRA, dataset preparation, instruction tuning and model evaluation.
RAG pipelines
Ingestion and chunking, vector and hybrid retrieval, reranking, and citation-backed, permission-aware answer systems.
Self-hosted inference
Deploying open-weight models on Ollama and vLLM, with quantisation, GPU sizing and high-throughput serving.
AI agent development
Agents that take real action through tool and function calling, bounded by human handoff and guardrails.
Automation & infrastructure
Workflow automation with n8n, Docker-based deployment and the operation of self-hosted systems.
CAREER
Experience
2021 — present
Founder & Technical Lead
Peaker Soft LLC (USA) · Peaker Soft Yazılım San. Tic. Ltd. Şti. — Dicle Teknokent, Diyarbakır
Founded the company and positioned it around artificial intelligence. As sole technical founder he builds its industry-specific SaaS products and the solution architecture of client projects, carrying responsibility for its LLM training, local deployment, RAG and AI agent work.
Software Development Specialist
Asis Elektronik ve Bilişim Sistemleri A.Ş.
Full-time software development in intelligent transport and information systems.
Senior Web Programmer
Cantaş İç ve Dış Tic. Soğutma Sist. San. A.Ş.
Building corporate web and business applications in the refrigeration systems sector.
15 years
Non-Commissioned Officer
Turkish Armed Forces
After fifteen years of service he resigned to focus full-time on his own projects and his company.
EDUCATION
Academic background
BSc — Management Information Systems
Anadolu University
Computer Programming
Süleyman Demirel University
OUTSIDE TECHNOLOGY
The shooting range, the clarinet and the microphone
A national athlete and coach in air pistol and precision shooting. He represented Türkiye at the 2019 Air Weapons World Cup in Beijing and holds a Turkish Air Pistol League title.
He is a musician and plays the clarinet, and also works as a voice actor.
National athlete & coach
Air pistol · precision shooting
Musician
Clarinet
Voice actor
Professional voice work
SELECTED WORK
Projects he has built
Turkish Shooting and Hunting Federation
Design and development of the federation's corporate website.
Abisyon
A QR-based restaurant ordering SaaS product. A method patent application for it has been filed with TÜRKPATENT.
Bayturs / Beytos
A B2B tour operator platform.
konusanlar.com
Website design and development.
Talk to the founder directly.
Technical assessment comes from the person who will do the work, not from a sales team. Let's set up a short call.