Dan Avramescu, Developer in Lisbon, Portugal
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Dan Avramescu

Verified Expert  in Engineering

Bio

Dan is a full-stack web developer with a passion for technology, and since 2008, he's been building web projects as a consultant and freelance. He's developed several projects while leading internationally remote technical teams and co-founded and ran an online startup for two years. Dan's expertise includes various languages (JavaScript, PHP, and HTML), libraries/APIs (React and Node.js), platforms (WordPress), site speed optimization, among others.

Portfolio

Dan Avramescu Freelance
AI Prompts, Next.js, Node.js, React, Large Language Models (LLMs)...
Grapevine Technologies
React, Node.js, MongoDB, PostgreSQL, CSS, HTML, Heroku, Git, Compass, Postman...
Freelance Work
Google SEO, Socket.IO, Site Speed Optimization, Git, JSON, Web Services, CSS...

Experience

  • JavaScript - 16 years
  • PHP - 13 years
  • CSS - 13 years
  • Full-stack - 11 years
  • Site Speed Optimization - 5 years
  • Node.js - 5 years
  • React - 5 years
  • Redux - 4 years

Availability

Full-time

Preferred Environment

Visual Studio Code (VS Code), CSS, PHP, React Redux, Node.js, React, JavaScript, Postman, Next.js, Artificial Intelligence (AI)

The most amazing...

...thing I've built was my startup. I created all the code, grew the team (from two to eight people), and saw the revenue increase from 0 to $600,000 in 18 months.

Work Experience

Software Engineer

2024 - PRESENT
Dan Avramescu Freelance
  • Integrated LLMs and LLM APIs for code generation and debugging. What used to take me hours of writing boilerplate React components and Node.js APIs now happens 2-3x faster with AI assistance.
  • Started incorporating LLM APIs into real client projects for data processing and analysis tasks. I now use LLM models to extract and categorize information and reduce development and delivery time.
  • Became an expert at prompt engineering for development tasks and quality code review of AI-generated solutions.
  • Learned to leverage AI for quick MVPs and demos. Using tools like ChatGPT for initial architecture planning, Claude for code review, and various AI APIs for functionality, I can now build working prototypes in days rather than weeks.
  • Developed expertise in integrating AI services into web applications. I understand the different LLM APIs, how to handle rate limiting, cost optimization, and building solid systems that handle AI service outages.
Technologies: AI Prompts, Next.js, Node.js, React, Large Language Models (LLMs), Large Language Model Operations (LLMOps), APIs, n8n, Gumroad API, Zapier, ChatGPT, OpenAI, Claude, Gemini, Gemini API, OpenAI API, Anthropic, Cursor AI, AI Agents, Event-driven Architecture, Microservices, Express.js, Docker, API Integration, Data Structures, Database Architecture, Databases, CI/CD Pipelines, Firebase, Content Management Systems (CMS), Strapi, Tailwind CSS, Figma, Vercel, Supabase, Cloudflare

CTO

2022 - 2024
Grapevine Technologies
  • Designed the architecture and created a second supply chain application meant to serve business users who need to perform complex operations, from inventory management to managing orders internally and externally to their clients.
  • Grew the team from three to eight developers, hired four testers, and integrated them into the team. Assured Agile development is well implemented, and features are shipped on a 2-week sprint basis.
  • Engineered search algorithms that scaled seamlessly from hundreds to tens of thousands of products, architecting back-end solutions that got faster as our product catalog increased.
Technologies: React, Node.js, MongoDB, PostgreSQL, CSS, HTML, Heroku, Git, Compass, Postman, JavaScript, SQL, TypeScript, Next.js, Startups, Artificial Intelligence (AI), CTO, Full-stack Development, Event-driven Architecture, Microservices, Express.js, Docker, API Integration, Agile Software Development, Architecture, Data Structures, Database Architecture, Databases, Technical Leadership, CI/CD Pipelines, Solution Architecture, Security, Stripe, Firebase, Figma, Vercel, Supabase, Cloudflare

Senior Web Developer

2014 - 2023
Freelance Work
  • Developed and maintained many websites and web applications while working extensively with publishers to create a great web experience for their readers and give them a technical edge in acquiring SEO traffic.
  • Helped my clients increase their monthly visitor count from a few thousand to 400,000 while their sites were under my technical supervision and maintenance.
  • Kept my clients' sites up to date with the new developments in web requirements (site speed, technical SEO, and visual design trends).
  • Developed and maintained more than 25 web projects.
  • Integrated various web services: content/product feeds, automatic SMS notification/authentication services, real-time client communication, and server using Socket.IO/polling.
Technologies: Google SEO, Socket.IO, Site Speed Optimization, Git, JSON, Web Services, CSS, HTML, WordPress, Drupal, Node.js, React, JavaScript, React Redux, REST APIs, PhpStorm, Postman, Operating Systems, XML Web Services, SCSS, jQuery, Software Architecture, SQL, TypeScript, Startups, Artificial Intelligence (AI), Model Context Protocol (MCP), Full-stack Development, ChatGPT, Large Language Model Operations (LLMOps), Large Language Models (LLMs), Event-driven Architecture, Microservices, Express.js, Docker, API Integration, Architecture, Data Structures, Database Architecture, Databases, CI/CD Pipelines, Solution Architecture, Security, Content Management Systems (CMS), Figma, Vercel, Cloudflare

JavaScript Engineer

2020 - 2021
Freelance
  • Participated in improving an app that offers an online theatrical experience with interactive participation of the viewers.
  • Ensured that certain visual and audio tracks were synchronized for all users, regardless of location, and showed the start time.
  • Designed an algorithm that allows users with connection issues to resume the theatrical experience at an opportune time.
Technologies: JavaScript, Twilio API, Ruby on Rails (RoR), HTML, Ruby, Amazon S3 (AWS S3), Amazon Web Services (AWS), Express.js, API Integration, Data Structures, Databases, Security, Figma

CTO

2017 - 2020
Tradunity
  • Created a startup together with a business partner in the financial products sphere.
  • Coordinated the team and grew it from two to eight people while having both technical and non-technical employees.
  • Created and maintained the code for our community website and integrated various services into it using the Telegram Bot API, Discord Bots API, Twilio, Zendesk, Mailchimp, and so on.
  • Wore all the hats in the company, from technical development, HR responsibilities, partner relationships to creating and coordinating the marketing campaigns, and managing our finances.
Technologies: PHP, SCSS, CSS, HTML, JavaScript, Node.js, Twilio, Telegram Bots, Discord, Google Tag Manager API, Google Analytics API, Tracking, Zendesk API, PhpStorm, Postman, XML Web Services, jQuery, Software Architecture, SQL, Startups, CTO, Full-stack Development, Agile Software Development, Architecture, Data Structures, Database Architecture, Databases, Technical Leadership, Security, Figma

Senior Web Development Consultant

2014 - 2017
Altelog
  • Stepped up to working as a consultant within top tier French companies and French government institutes.
  • Integrated the front-end landing pages with high conversion rates for a Drupal 7 application. The client was Cellfish Media, a fast-paced mobile online marketing company.
  • Led a team of developers to create the front-end themes and the back end of two government websites in Drupal 7.
  • Served as the lead developer for a startup financed by Engie called Green Channel—integrating clients via Salesforce and creating the front-end theme in a Drupal 7 application.
Technologies: Gulp, Stylus, SCSS, CSS, HTML, JavaScript, PHP, Drupal, Affiliate Tracking, PhpStorm, Postman, XML Web Services, jQuery, SQL, Agile Software Development, Data Structures, Databases, Technical Leadership, Security, Content Management Systems (CMS), Figma

Web Development Consultant

2013 - 2014
Algo-Expert
  • Trained my colleagues in Drupal 7 and taught them the differences between Drupal 6 and 7.
  • Worked as a consultant while being based in Paris.
  • Maintained 2 Drupal applications for clients in Paris.
Technologies: CSS, HTML, JavaScript, PHP, Full-stack, PhpStorm, XML Web Services, SCSS, jQuery, SQL, Data Structures, Databases, Content Management Systems (CMS)

Web Developer

2012 - 2013
Cybervision
  • Maintained and evolved several client websites in Drupal 6/7 and Joomla.
  • Tracked and fixed bugs in Redmine and Jira and created workflows for client feedback and bug resolution.
  • Participated in client briefs, contract negotiation, requirements analysis, and offer creation.
Technologies: Joomla, Drupal 7, Drupal 6, CSS, HTML, JavaScript, PHP, Full-stack, XML Web Services, jQuery, SQL, Data Structures, Databases

Web Developer

2008 - 2010
Uniway
  • Developed two websites in Drupal 6 for a steel company and a news outlet in Belgium.
  • Created the themes that adhered to Drupal 6 standards at that time.
  • Integrated a web service that sent and received XML data. This was 2008, so quite complex for its time.
Technologies: Drupal 6, HTML, CSS, JavaScript, PHP, Full-stack, XML Web Services, jQuery, SQL, Java, Data Structures, Databases

Experience

Grapevine ERP App

https://grapevine.com
A React/Node.js/MongoDB-based app that allows companies to manage their stocks across multiple warehouses, add and manage client contacts, and create internal and external orders with several payment types.

React Administration UI and JavaScript Show Runner for Online Theatrical Experiences

AnyOneThing creates online theatrical experiences that often get the viewer to participate in the play through his microphone and/or camera. I was tasked with creating an administrative UI with React, which interfaces the back-end API (written in Ruby on Rails) and facilitates administrators to edit the sequences of scenes and theatrical cues (videos, audios, images, and sounds).

Moreover, I created a box office application (also in React) and optimized and evolved the showrunner to work across browsers and offer a better overall experience.

Tradunity

I was part of a two-founder team of Tradunity: a bootstrapped startup. Our goal was to help beginner traders find success in the financial markets.

I was responsible for technical development and leading the technical team as we grew. I also created the original app and integrated it with all the vital services we needed to create a thriving community.

As our team grew to eight people, so did my responsibilities. We created and executed a very efficient product and promotion strategy, which led to great results. Tradunity has turned a profit from the first month up until the beginning of 2020. The project was closed at the beginning of 2020.

ClassRoomQ | Node.js and React App

https://classroomq.com
ClassRoomQ is a Node.js and React app that allows students and teachers in virtual classrooms to interact with each other in a structured way. There were two authorization levels. The authentication had to be done through a middleware that could identify users who were already logged in to a WordPress application. The Node.js and React interaction was done through WebSockets rather than an API to facilitate the two-way interaction between authenticated and anonymous users.

Education

2010 - 2012

Master's Degree in Computer Science

Technical University of Delft - Delft, The Netherlands

2006 - 2010

Bachelor's Degree in Computer Science

Politechnics University of Bucharest - Bucharest, Romania

Skills

Libraries/APIs

React, Node.js, jQuery, REST APIs, React Redux, Telegram Messenger API, Socket.IO, Telegram Bot API, Twilio API, Antd, Google Tag Manager API, Google Analytics API, Zendesk API, Gumroad API, OpenAI API, Stripe

Tools

Git, PhpStorm, JSX, ChatGPT, Postman, Google Analytics, AI Prompts, Figma, Stylus, Gulp, Subversion (SVN), Mailchimp, LearnDash, Claude, n8n, Zapier

Languages

JavaScript, PHP, CSS, HTML, SQL, TypeScript, C, C++, SCSS, Java, Ruby, Python

Frameworks

Express.js, Next.js, Redux, Tailwind CSS, Compass, Ruby on Rails (RoR)

Paradigms

Event-driven Architecture, Microservices, Agile Software Development, Waterfall Development, Model Context Protocol (MCP)

Platforms

WordPress, Vercel, Docker, Firebase, Visual Studio Code (VS Code), Drupal 6, Drupal 7, Joomla, Drupal, Zendesk, Twilio, Heroku, Amazon Web Services (AWS)

Storage

JSON, Database Architecture, Databases, MongoDB, MySQL, PostgreSQL, Amazon S3 (AWS S3)

Other

Site Speed Optimization, Full-stack, Back-end, Front-end, Startups, CTO, Full-stack Development, Cursor AI, API Integration, Architecture, Data Structures, Technical Leadership, Content Management Systems (CMS), Web Services, Google SEO, APIs, Axios, Artificial Intelligence (AI), OpenAI, ChatGPT API, ChatGPT Prompts, Prompt Engineering, Software Architecture, Large Language Model Operations (LLMOps), Large Language Models (LLMs), AI Agents, Solution Architecture, Security, Strapi, Supabase, Cloudflare, Operating Systems, XML Web Services, UML Diagrams, Wireless Sensor Networks, Discord Bots, Affiliate Tracking, Google Tag Manager, Computer Science, WebSockets, EMCAScript (ES), Telegram Bots, Discord, Tracking, Gemini, Gemini API, Anthropic, CI/CD Pipelines

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