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Simon Rendon Arango, CV

Software and AI engineer. London, United Kingdom.

I hold an MSc in Computing (Software Engineering) from Imperial College London and a BSc in Systems and Computing Engineering from Universidad de los Andes. Since 2023 I have built LLM systems that run in production. At Glamper I built an LLM travel agent, and bookings grew by more than 50%. At Untap I built a pipeline that extracts KPIs from financial reports with 90%+ accuracy. It cut client data ingestion time by more than 80%. I also built a RAG system and an MCP server over portfolio data there. Since June 2026 I have been on the research team at Tessl. We are architecting the software factory, an AI-native platform where coding agents design, build and verify production software. I lead model evaluation, and I shape context evaluation and code verification.

On the side I build LFM, a football model that is in progress. I also made EvalLens, an open-source tool that checks structured LLM outputs. I am from Medellín, Colombia. I moved to London in 2023 for my MSc.

Experience

Newest first.

  1. Jun 2026 to nowLondon, United Kingdom

    TesslAI Research

    • Core member of Tessl's research team, architecting the software factory: an AI-native platform where coding agents design, build and verify production software
    • Lead model evaluation, benchmarking frontier LLMs to select the optimal model for every agentic task
    • Pioneer context evaluation, quantifying how documentation, specifications and tooling shape agent accuracy, and channel those insights into the product
    • Engineer the code verification layer that safeguards the correctness of agent-generated code before it reaches users

  2. Nov 2024 to Jun 2026London, United Kingdom

    UntapSoftware Engineer

    • Built an LLM pipeline for Untap's private-equity platform that extracts KPIs, targets and cashflows from financial reports with 90%+ accuracy. It cut client data ingestion time by more than 80%
    • Built a RAG system over BigQuery and Gemini, and an MCP server that gives LLMs access to internal tools

    Projects at Untap

    • Financial data extraction

      An LLM pipeline that extracts KPIs, cashflows, targets and named entities from financial documents. I fine-tuned the model and wrote the prompts. Accuracy is above 90%.

    • Investor intelligence system

      A RAG system and an MCP server that let analysts ask questions about portfolio data in plain English.

  3. Mar 2023 to Sep 2023Colombia

    GlamperSoftware Engineer

    • Designed and built a serverless backend on AWS Lambda and API Gateway for bookings, payments and users
    • Built an LLM travel agent that plans full trips from the current inventory. Bookings grew by more than 50%
    • Built and maintained the Vue and Nuxt web app

  4. Jul 2021 to Jan 2022Colombia

    BancolombiaIntern Software Engineer

    • Built Jira and AWS integrations and a React KPI dashboard for the infrastructure team (Nequi). Ticket resolution time fell by 35%
    • Automated cloud migration workflows during the bank’s move from on-premise to AWS

Education

Each degree ended with a thesis in machine learning.

  1. Sep 2023 to Sep 2024London, United Kingdom

    Imperial College LondonMaster of Science in Computing (Software Engineering)

    Thesis: Performance regression detection in HPC (Nektar++). Regression triage time cut from days to under 2 hours.

  2. 2018 to 2023Colombia

    Universidad de los AndesBachelor of Science in Systems and Computing Engineering

    Thesis: Predicting Formula 1 results with machine learning. About 93% accuracy on race winners.

Selected work

Projects I build in my own time.

  1. 2026open source

    EvalLens

    An open-source tool that checks structured LLM outputs against expected schemas and values, row by row, and names the reason for every failure.

    rendonarango.com/eval-lensgithub.com/SimonRendonA/eval-lens

  2. 2025 to nowin progress

    Large Football Model

    A football model I am building. It will give match probabilities during a game, find similar players and matches, and simulate matches. It is not public yet. The page has a waitlist.

    rendonarango.com/lfm

  3. 2026a map of my CV

    The Constellation

    Each star is a degree, a job or a project from my CV. 4 lenses group the stars by topic.

    rendonarango.com/constellation

  4. 2026iPhone and iPad app · in progress

    Intus

    An iPhone and iPad app for habits and a journal that I am building. Each morning and evening a model writes a short card from your entries. The text goes to the model only for that call and is not stored.

    useintus.com

Skills

My core and strong skills, by area.

  1. AI and LLMs

    Agents, Evals, RAG, LLMs, MCP

  2. Languages

    TypeScript, Python, JavaScript, Java

  3. Machine learning

    Deep learning, Reinforcement learning, TensorFlow, Scikit-learn, Pandas, NumPy, Data visualisation

  4. Web

    React, Next.js, Node.js, Express, Tailwind CSS, Framer Motion, shadcn/ui

  5. Cloud and tools

    GCP, AWS, Docker, CI/CD, GitLab

Generated from the data on rendonarango.com. Last revised November 2026.

Simon Rendon Arango, London

Set in Sofia Sans and Sofia Sans Extra Condensed. Built with Next.js. Last revised November 2026.