Kostandin Angjellari
Full-Stack Engineer & Founder | Nodejs | React | AI
10 years building across SaaS, Fintech, Multimedia, and lately AI. Co-founded Quinvio, an AI video presentation platform that grew to 25K users and 500+ paying customers. Love leading engineering teams, bridging product and code, and craft from 0 to 1.
Work Experience
Senior Full-Stack Engineer - TrustLayer | Sep 2024 - Sep 2025
- Built end-to-end features in a ShapeUp workflow as the platform was scaling.
- Contributed on evolving the stack with additions such as Postgres, Drizzle, Remix and Temporal.
Product Engineer - Cofactory | Sep 2023 - Mar 2024
- Led a team of 3 full-stack engineers on building RAG with LangChain, Next.js, Qdrant, Postgres.
- Worked closely with the founders/PO to take AI products quickly to market.
Co-founder - Quinvio | Mar 2021 - Jul 2024
- Bootstrapped AI video platform to 25K users and 500+ paying customers.
- Designed multimedia AI pipeline and rich React/Node.js video editor.
- Led product initiatives, user research, and partnerships to drive growth.
Engineering Lead, Core Team - Ritech | Aug 2018 - Jun 2021
- Co-led fintech platform aggregator integrating multiple US financial vendors.
- Built WebRTC / Frontend infrastructure for video conferencing platform.
- Established engineering standards and processes to improve team efficiency.
Engineering Lead - Softup Technologies | Nov 2017 - Aug 2018
- Migrated legacy HR SaaS platform to Node.js & GraphQL.
- Defined engineering standards, CI/CD pipelines, and code review practices.
Senior Backend Engineer - Airfind | May 2016 - Jun 2017
- Built AdTech products in scale for OEMs including ZTE and USCellular.
- Improved platform performance 30% via Redis, MongoDB, and task queues.
Engineering Lead - Prius Solutions | May 2015 - May 2016
- Led a team of 5, delivering B2B platforms in Java EE, AngularJS, PostgreSQL.
- Shipped 5 SaaS and B2C products for local and regional market.
Full-Stack Developer - Techmobile | May 2014 - May 2015
- Built ERP solutions with Java EE for enterprises like Vodafone and Eni.
- Built and maintained vanilla javascript library for building dynamic forms.
Skills
Languages:
- TypeScript, Go, Python
Frameworks:
- Node, React, Next, Remix, GraphQL
Databases:
- PostgreSQL, MongoDB, Redis, Elasticsearch, Qdrant
Messaging:
- RabbitMQ, BullMQ, SQS, Kafka, Temporal
Cloud/DevOps:
- AWS, GCP, Docker, Terraform, Kubernetes, Helm
AI/ML:
- LangChain, LlamaIndex, LLMs, Claude Code, SDD, RAG
Other:
- Engineering leadership, Product Strategy, Startups
Education
- Studied Computer Science, University of Tirana (2012-2015)