Cristhian is available for hire
Hire CristhianCristhian Camilo Gomez Neira
Verified Expert in Engineering
Full-stack Developer
Bogotá - Bogota, Colombia
Toptal member since September 29, 2021
Bio
Cristhian is a back-end developer and data scientist passionate about algorithms, data science, and software development. He has experience in back-end design, software architecture, machine learning model design, and algorithm definition. Cristhian is a fast learner, and he is studying every day to improve his knowledge and skills.
Portfolio
XBuild
Python 3, Large Language Models (LLMs), Python, Machine Learning...
Handit AI
Python, Machine Learning, Large Language Models (LLMs), Open Source...
Fullscript - Natural Partners Inc
Ruby, Stripe, Stripe Payments, Stripe API
Experience
- Data Science - 7 years
- JavaScript - 5 years
- Software Development - 4 years
- Software Architecture - 4 years
- Neural Networks - 3 years
- Algorithms - 3 years
- Camunda BPM - 2 years
- Elasticsearch - 2 years
Preferred Environment
Camunda BPM, Elasticsearch, Apache Airflow, Docker, Node.js, JSX, Python 3, React, Vue, Ruby on Rails (RoR)
The most amazing...
...thing I've implemented is a complete recommender machine learning system for matching people with potential projects in a marketplace for voice actors.
Work Experience
Senior AI Researcher and Engineer
2025 - PRESENT
XBuild
- Built XBuild's estimation agent end-to-end—a single-loop AI agent that produces construction-sector estimations across diverse file types and project contexts.
- Designed the agent's dynamic context and dynamic-effort system, enabling the program to self-tune how much reasoning and context it applies per task to maximize estimation quality.
- Developed supporting platform software and tooling around the agent, from file/context handling to production reliability.
Technologies: Python 3, Large Language Models (LLMs), Python, Machine Learning, Artificial Intelligence (AI)
CTO
2024 - 2026
Handit AI
- Led all engineering as CTO and principal implementer of Handit, an open-source AI reliability platform that autonomously detects production AI failures, generates fixes, tests them, and ships GitHub pull requests.
- Built the LLM-as-judge evaluation and observability layer that traces every agent interaction and continuously scores output quality—catching hallucinations, schema violations, PII leaks, and performance regressions in real time.
- Designed and implemented the self-improving optimization loop, applying genetic algorithms to evolve prompt and system variants and automatically promote the highest-performing candidates.
Technologies: Python, Machine Learning, Large Language Models (LLMs), Open Source, Data Science
Senior Ruby Engineer
2024 - 2025
Fullscript - Natural Partners Inc
- Architected and shipped the end-to-end lab testing commerce system, enabling practitioners to order, sell, and fulfill diagnostic lab tests directly through the platform.
- Built the payment infrastructure for lab and supplement orders on Stripe (Payments, Connect, webhooks), handling authorization, capture, refunds, and split payouts across practitioners and clinics.
- Collaborate with multiple teams on the core functionalities of shipment and payments.
Technologies: Ruby, Stripe, Stripe Payments, Stripe API
LLM Expert | Full-stack Python Developer
2023 - 2023
Higher Bar AI, PBC
- Developed an app where clients can use an LLM to process and evaluate surveys.
- Developed a system that can parse surveys in any format, evaluate them, and give recommendations using different evaluation lenses.
- Used the feedback that users gave to the service to improve the LLM and provide accurate results.
Technologies: Python, React, AWS Amplify, AWS Fargate, Amazon Web Services (AWS), Amazon Cognito, Data Engineering, ETL, OpenAI GPT-4 API, Vector Data, OpenAI GPT-3 API, Language Models, Hugging Face, Chatbots, Natural Language Understanding (NLU), OpenAI, Stripe, Fine-tuning, Large Language Models (LLMs), Retrieval-augmented Generation (RAG), Big Data, Prompt Engineering, Vector Databases, Back-end Performance, Design Language, MLflow, LangChain, Model Deployment, AI Modeling
Web Developer | OpenAI API Expert
2023 - 2023
C.M. Dillon Company inc
- Developed a quote management application that the client uses daily.
- Used GPT to make automatic quotes based on emails and text.
- Connected the application with QuickBooks Desktop SDK, making it do stable updates every minute.
Technologies: JavaScript, Web Development, OpenAI API, Full-stack, ChatGPT, Artificial Intelligence (AI), Language Models, Hugging Face, NestJS, OpenAI, Fine-tuning, Large Language Models (LLMs), Retrieval-augmented Generation (RAG), Prompt Engineering, QuickBooks API, OpenAI GPT-3 API, OpenAI GPT-4 API, Vector Databases, Back-end Performance, Design Language
AI Expert | React and Python Developer
2022 - 2023
Alex S Montgomery
- Improved computer vision models to apply face swapping to images and videos.
- Created multiple new features for the platform and integrated it with multiple systems.
- Improved the architecture of the application and the servers management.
Technologies: Computer Vision, React, Python, OpenCV, Machine Learning, Artificial Intelligence (AI), Web Development, Full-stack, API Integration, API Development, Solution Architecture, Full-stack Development, AI Design, Automation, Process Automation, Pandas, SQLAlchemy, FastAPI, DataFrames, Front-end, Front-end Development, Back-end Development, Unit Testing, Flask, Three.js, Git, Lint, Agile, Databases, Serverless, Lambda Functions, CI/CD Pipelines, Code Review, Estimations, Data Processing, Expo, Google Cloud Platform (GCP), Data Lakes, Back-end Performance, MLflow
Senior Ruby on Rails Developer
2022 - 2023
Farmgirl Flowers
- Refactored the platform to make it more stable and make the code cleaner.
- Implemented new key features on the platform related to tracking and order management.
- Created documentation for the site, explaining the processes of the company and the code.
Technologies: Ruby on Rails (RoR), Heroku, Amazon Web Services (AWS), Team Management, Communication, Web Development, Full-stack, API Integration, API Development, Solution Architecture, Full-stack Development, Automation, Kubernetes, Architecture, Front-end, Back-end Development, Docker Hub, Git, Agile, Databases, Lambda Functions, CI/CD Pipelines, Code Review, Estimations, Technical Leadership, Back-end Performance, Team Leadership, Design Patterns, Stripe Payments, Stripe API
Full-stack Developer | React and RoR
2022 - 2023
Springboard Collaborative Inc.
- Developed multiple features inside the platform to enhance the user experience better.
- Solved multiple bugs directly affecting the platform and the application's functionality.
- Created documentation for the engineering processes of the company.
- Involved in these activities to join and participate in the innovative project.
Technologies: Ruby on Rails (RoR), JavaScript, React, Scrum, Agile, APIs, SQL, Responsive UI, Rails Engines, Communication, Web Development, Full-stack, API Integration, API Development, Solution Architecture, Full-stack Development, Kubernetes, Architecture, Front-end, Front-end Development, Back-end Development, Unit Testing, Docker Hub, Git, Lint, Databases, CI/CD Pipelines, Code Review, Estimations, Data Scraping, Google Cloud Platform (GCP), Back-end Performance, Team Leadership, Design Patterns
Algorithm Engineer
2021 - 2023
Voice123
- Optimized the search algorithm to improve the click-through rate of the platform.
- Improved the quality of the invitations sent to voice actors using a recommender system.
- Enhanced the algorithm that predicts the number of people that need to be invited to fulfill a project using machine learning and data science methods.
- Created an automatic tagging system to organize and analyze the information of voice actors in the platform.
- Developed a categorization message model to organize data about messages in the platform and prevent spam.
Technologies: Python, Algorithms, Data Science, Machine Learning, Camunda BPM, Apache Airflow, Node.js, JavaScript, Elasticsearch, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), Convolutional Neural Networks (CNNs), TensorFlow, Sequence Models, Deep Neural Networks (DNNs), Software Development, Software Design, Docker, Python 3, Back-end, MySQL, PostgreSQL, Amazon Web Services (AWS), APIs, REST APIs, CSS, TypeScript, GitHub, HTML5, Express.js, Containers, MongoDB Atlas, AWS Lambda, Vue, Next.js, Communication, Web Development, API Integration, API Development, Solution Architecture, Leadership, Full-stack Development, AI Design, Automation, Process Automation, Google API, Google APIs, Kubernetes, Pandas, DataFrames, Architecture, Back-end Development, Unit Testing, Flask, Three.js, Docker Hub, Git, Lint, OpenAPI, Agile, Databases, Amazon EC2, Serverless, Lambda Functions, CI/CD Pipelines, Estimations, Technical Leadership, Data Processing, Hugging Face, NestJS, Chatbots, Google Cloud Platform (GCP), Natural Language Understanding (NLU), OpenAI, Fine-tuning, Large Language Models (LLMs), Big Data, Data Lakes, OpenAI GPT-3 API, OpenAI GPT-4 API, Language Models, Vector Databases, Back-end Performance, Design Language, Team Leadership, Design Patterns
Senior ML Developer
2021 - 2022
Authtech
- Developed a machine learning model that has the ability to detect flash patterns for authorization with high accuracy and a processing time of less than 30 ms.
- Optimized 5E models for high speed on mobile devices (Android and iOS).
- Created a mobile application and an SDK currently used by multiple users and companies for Android and iOS, using React Native, Swift, and Java.
Technologies: Algorithms, Machine Learning, TensorFlow, Computer Vision, iOS, Android, Redux, Communication, Web Development, API Integration, Artificial Intelligence (AI), API Development, Solution Architecture, Leadership, AI Design, Automation, Process Automation, Google API, Google APIs, Kubernetes, Django, Pandas, SQLAlchemy, FastAPI, DataFrames, Mobile Development, Back-end Development, Mobile, Unit Testing, Flask, Git, Agile, Serverless, Lambda Functions, CI/CD Pipelines, Data Scraping, Data Processing, Hugging Face, Swift, Xcode, Fine-tuning, Large Language Models (LLMs), Big Data, Data Lakes, Language Models, Back-end Performance, Team Leadership, Model Deployment, LangChain, AI Modeling
AI Expert | Python Back-end Developer
2021 - 2022
Notitia Technologies Inc.
- Developed multiple features inside the platform to transform PDF and Microsoft documents into textual information, making it available to search engines.
- Optimized the process inside the platform so documents could be received and processed in a fraction of a second.
- Solved multiple high bugs directly affecting the platform and the application's functionality.
- Engaged hourly as an experienced developer to document parsing for this AI startup.
Technologies: Python, GraphQL, AWS Amplify, Amazon Web Services (AWS), React, Communication, Web Development, API Integration, Artificial Intelligence (AI), API Development, Solution Architecture, AI Design, Automation, Process Automation, Google API, Google APIs, Django, Pandas, SQLAlchemy, Back-end Development, Unit Testing, Flask, Docker Hub, Git, Agile, Databases, Serverless, CI/CD Pipelines, Data Scraping, Data Processing, Amazon S3 (AWS S3), Fine-tuning, Large Language Models (LLMs), Back-end Performance
Back-end Developer | Express and Node.js
2021 - 2021
b.plat LLC
- Developed new features on an application that serves multiple users in the USA.
- Developed ML models to solve multiple problems in the company.
- Created multiple scripts to automatize data preprocessing.
Technologies: Node.js, JavaScript, Express.js, MongoDB, TypeScript, Amazon Web Services (AWS), Python 3, iOS, Android, Redux, Communication, Web Development, API Integration, API Development, Solution Architecture, Automation, Process Automation, Mobile Development, Architecture, Back-end Development, Unit Testing, Git, Lint, Agile, Databases, Amazon EC2, CI/CD Pipelines, Data Processing, Expo, Amazon S3 (AWS S3), Amazon API Gateway, Stripe, Back-end Performance, Design Patterns, Stripe Payments, Stripe API, Dart
Full-stack Developer
2020 - 2020
Voice123
- Started the internationalization and localization efforts of the platform.
- Tracked and fixed different bugs of high impact on the platform.
- Spearheaded the optimization of the company's central algorithms.
Technologies: Node.js, Camunda BPM, Elasticsearch, Apache Airflow, JavaScript, Software Development, Software Design, Docker, Back-end, MySQL, PostgreSQL, Amazon Web Services (AWS), APIs, REST APIs, CSS, TypeScript, GitHub, HTML5, Express.js, Containers, MongoDB Atlas, AWS Lambda, Responsive UI, Communication, Web Development, Full-stack, API Integration, API Development, Solution Architecture, Full-stack Development, Google API, Google APIs, Kubernetes, Mobile Development, Front-end, Front-end Development, Back-end Development, Mobile, Unit Testing, Docker Hub, Git, Lint, Agile, Databases, Amazon EC2, CI/CD Pipelines, Google Cloud Platform (GCP), Amazon S3 (AWS S3), Amazon API Gateway, Stripe, Back-end Performance, Design Patterns, Stripe Payments, Stripe API
Full-stack Developer | Product Manager
2019 - 2019
Cargapp
- Developed a web management system for load generators to search for truck drivers that could transport their products.
- Developed a mobile app for truck drivers integrated with a tracking system and a real-time database to take jobs that fit their needs.
- Helped the management team to make decisions based on data analysis and mathematical models.
Technologies: Node.js, JavaScript, React, Ruby on Rails (RoR), Software Development, Software Design, Software Architecture, IT Project Management, DevOps, React Native, Back-end, MySQL, PostgreSQL, Amazon Web Services (AWS), APIs, Linux, MongoDB, REST APIs, HTML, CSS, GitHub, GitHub API, HTML5, Bootstrap, Ruby on Rails 5, Express.js, Ruby, Firebase Authentication, Responsive UI, Communication, Web Development, Full-stack, API Integration, API Development, Full-stack Development, Front-end, Front-end Development, Back-end Development, Mobile, Git, Lint, Agile, Databases, Amazon EC2, Xcode, Amazon S3 (AWS S3), Stripe, Design Patterns, Flutter
Full-stack Developer
2019 - 2019
VegaMedia Group
- Integrated multiple tracking and control systems of various trucks.
- Implemented a complete tracking system that gives real-time information to managers about the location, speed, and acceleration of trucks and gives alerts if the truck drivers stay in the same place for a long time.
- Analyzed relevant data so managers can have the most optimal routes and understand the behavior of the truck drivers on different routes.
Technologies: PHP, Node.js, C++, Software Development, Software Design, Software Architecture, IT Project Management, DevOps, JavaScript, Firebase, Back-end, MySQL, MariaDB, Amazon Web Services (AWS), APIs, Linux, MongoDB, REST APIs, HTML, CSS, GitHub, GitHub API, HTML5, Bootstrap, Express.js, React, Responsive UI, Communication, Web Development, Full-stack, API Integration, API Development, Full-stack Development, Front-end, Front-end Development, Back-end Development, Mobile, Git, Lint, Agile, Databases, Xcode, Amazon S3 (AWS S3), Amazon API Gateway
Full-stack Developer | Project Manager
2018 - 2019
MB Media Digital
- Developed five different web applications and eCommerce used by big companies in the music industry.
- Created a complete tracking architecture so clients can have control in real-time about the health of the systems.
- Implemented intelligent systems that help the business managers to make decisions and do data analysis.
Technologies: PHP, Node.js, Ruby on Rails 4, React, Software Development, Software Design, Software Architecture, IT Project Management, DevOps, Firebase, GPS, Back-end, MySQL, MariaDB, Amazon Web Services (AWS), APIs, Linux, MongoDB, REST APIs, HTML, CSS, GitHub, GitHub API, HTML5, Bootstrap, Ruby on Rails 5, Ruby on Rails (RoR), Express.js, Ruby, Firebase Authentication, Communication, Web Development, Full-stack, API Integration, API Development, Full-stack Development, Front-end, Front-end Development, Back-end Development, Git, Lint, Databases, Amazon S3 (AWS S3), Amazon API Gateway
Experience
Voice123
http://www.voice123.comVoice123 is a worldwide marketplace for professional voice actors where I acted as the platform's algorithm engineer and data scientist, analyzing data daily, designing models and algorithms based on data, maintaining the platform algorithms, and implementing new algorithms in the back-end, using technologies such as Elasticsearch Camunda, Node.js, and Apache Airflow.
Cargapp App for Truck Drivers
A React Native application connected to a Ruby on Rails back end and a tracking system made in PHP. The application used a real-time database so managers of truck drivers could see the information and location of their trucks.
VegaMedia Tracking System
VegaMedia is a PHP tracking system that integrates external GPS services and gets signals and information for Raspberry Pis connected to trucks around the country. The tracking system helps big companies keep track of their trucks, evaluate the behavior of their truck drivers, and helps them select the most appropriate routes.
Farmgirl Flowers Platform
A Ruby on Rails and React-based retail shop that sells flowers to the US. The application has integration with multiple APIs and also offers an incredible user experience. I was part of the refactoring team, so we stabilized the application, made it better for the end user, and improved the code to make it cleaner.
Education
2022 - 2025
Master's Degree in Computer Science
National University of Colombia - Bogota, Colombia
2017 - 2023
Bachelor's Degree in Mathematics
National University of Colombia - Bogota, Colombia
2015 - 2021
Bachelor's Degree in Computer Science
National University of Colombia - Bogotá, Colombia
Certifications
JANUARY 2021 - PRESENT
Sequences, Time Series and Prediction
Coursera
JANUARY 2021 - PRESENT
Sequence Models
Coursera
JANUARY 2021 - PRESENT
Natural Language Processing in TensorFlow
Coursera
JANUARY 2021 - PRESENT
Introduction to TensorFlow for Artificial Intelligence, Machine Learning, and Deep Learning
Coursera
JANUARY 2021 - PRESENT
DeepLearning.AI TensorFlow Developer Specialization
Coursera
JANUARY 2021 - PRESENT
Convolutional Neural Networks in TensorFlow
Coursera
JULY 2020 - PRESENT
Convolutional Neural Networks
Coursera
JUNE 2020 - PRESENT
Structuring Machine Learning Projects
Coursera
OCTOBER 2017 - PRESENT
Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization
Coursera
SEPTEMBER 2017 - PRESENT
Neural Networks and Deep Learning
Coursera
JULY 2017 - PRESENT
Machine Learning
Coursera
Skills
Libraries/APIs
Node.js, React, REST APIs, API Development, Pandas, TensorFlow, GitHub API, AWS Amplify, Google API, Google APIs, SQLAlchemy, Three.js, Stripe, Stripe API, Vue, Rails Engines, OpenCV, OpenAPI, OpenAI API, QuickBooks API
Tools
Slack, Visual Studio, GitHub, Git, Expo, Xcode, Camunda BPM, Firebase Authentication, MongoDB Atlas, Docker Hub, AWS Fargate, Amazon Cognito, Apache Airflow, JSX, ChatGPT
Languages
JavaScript, Python, Python 3, HTML, CSS, TypeScript, HTML5, Ruby, SQL, C++, GraphQL, Swift, Java, PHP, C#, Dart
Frameworks
Ruby on Rails (RoR), React Native, Express.js, Next.js, Bootstrap, Ruby on Rails 5, Redux, Django, Flask, NestJS, Ruby on Rails 4, Flutter
Paradigms
Agile, Mobile Development, Unit Testing, ETL, Design Patterns, Automation, DevOps, Scrum
Platforms
MacOS, iOS, Kubernetes, Amazon EC2, Google Cloud Platform (GCP), Docker, Firebase, Amazon Web Services (AWS), Linux, AWS Lambda, Heroku, Android, Mobile
Storage
Elasticsearch, MySQL, PostgreSQL, MariaDB, Databases, Amazon S3 (AWS S3), MongoDB, Data Lakes
Other
Data Science, Back-end, APIs, Communication, Web Development, Full-stack, API Integration, Full-stack Development, DataFrames, Architecture, Front-end, Front-end Development, Back-end Development, Lint, Data Engineering, Hugging Face, Big Data, Neural Networks, Convolutional Neural Networks (CNNs), Deep Learning, Machine Learning, Natural Language Processing (NLP), Sequence Models, Time Series, Deep Neural Networks (DNNs), Software Development, Software Design, Software Architecture, Algorithms, Containers, Responsive UI, Artificial Intelligence (AI), Generative Pre-trained Transformers (GPT), Solution Architecture, Leadership, AI Design, Process Automation, FastAPI, Serverless, Lambda Functions, CI/CD Pipelines, Code Review, Estimations, Technical Leadership, Data Scraping, Data Processing, OpenAI GPT-4 API, OpenAI GPT-3 API, Large Language Models (LLMs), Chatbots, Natural Language Understanding (NLU), Amazon API Gateway, OpenAI, Fine-tuning, Vector Databases, Back-end Performance, Design Language, Team Leadership, Stripe Payments, IT Project Management, GPS, Computer Vision, Team Management, Internet of Things (IoT), Mathematics, Complex Problem Solving, Modeling, Vector Data, Language Models, Prompt Engineering, Retrieval-augmented Generation (RAG), MLflow, LangChain, Model Deployment, AI Modeling, Probability Theory, Causal Inference, Open Source
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring