Neilor Caldeira

Software Engineer and Engineering Leader · Realtime, logistics and operations platforms

Belo Horizonte, Brazil (UTC-3) neilorcaldeira@gmail.com neilor.dev github.com/neilor linkedin.com/in/neilorcaldeira instagram.com/neilor.dev

Summary

Engineer with 15+ years building web software for real operations: fleets, hospitals, exchanges. Founded the engineering function of a 1,400-person road carrier and designed the platform that runs 20,000 partner drivers and 30,000 trips a month. Rebuilt the realtime layer of a national telehealth service during the 2020 emergency without taking it offline. Runs a 30-person company as director and still ships code.

Core expertise

Architecture: distributed realtime state, event-driven backends, monorepos, multi-tenant design, build-vs-buy decisions, ERP, EHR and IoT telemetry integration.

Stack: TypeScript, Node.js, React, Firebase (Realtime Database, Cloud Functions, Hosting), Google Cloud, MongoDB, PostgreSQL, BigQuery, Twilio, Terraform. Earlier: Ruby, PHP, Ember, Cordova/Ionic, React Native, Electron.

Experience

Co-founder · Kazan GroupJanuary 2026 to present

Built and operates Kazan Code Intelligence: AI agents that analyze a client's codebase (three-level knowledge layer, staleness control by source hash, explicit context budget) and produce decision documents for its board. First engagement, seven repositories: three P0 defects found in the first session, and a single-tenant vs multi-tenant decision that avoided a refactor estimated at several months.

Director of Operations · FACSS, telematics and fleet managementJune 2024 to present

Runs the company day to day (about 30 people, 11+ engineers): product, delivery, customers, vendors. Closed and kicked off the Aperam contract (telemetry and gamification for a mining operation); hired and manages offshore squads in India; led a telemetry vendor RFQ for 2,000+ trucks; negotiated Looker licensing directly with Google; Data Protection Officer.

Senior Staff Engineer, then CTO · Lenarge, road freight carrier (1,400 employees)2019 to 2024

Rejoined Lenarge with a proposal to create a technology directorate (approved in five business days), wrote the build-vs-buy case for the company's fleet platform, founded the engineering function from zero and designed the platform: TypeScript end to end, live fleet state on Firebase Realtime Database, MongoDB, PostgreSQL, SQL Server, BigQuery, 15+ telematics integrations. Responsible for its architecture through five versions.
In production for 20,000 partner drivers and 30,000 trips a month; automated monthly rewards for about 800 drivers a month; clients include Gerdau and Aperam. Led the telemetry integration with Gerdau's Oracle Transportation Management with Hitachi Consulting.

Senior Developer (contract, in parallel with Lenarge) · Iron Fit, digital health2020 to 2021

Cassi telehealth, Covid-19 emergency: the queue of Brazil's largest self-managed health plan was failing under load. Read the legacy code, wrote a new realtime layer on Firebase (device presence, indexed queues, optimistic transactions, Twilio Video) while the system stayed live, and coordinated an offshore squad for the rest. The queue became a live dashboard for clinical staff; the platform went on to 500,000+ consultations.
Hospital Sírio-Libanês, 2021: chose to integrate the primary-care program with the Philips Tasy EHR already in use (.NET Core, Oracle) through the InterSystems HealthShare bus, instead of a parallel record; technical lead in reports to hospital leadership; pilot live July 2021.

Senior Engineer, then technical lead · AllCoinWallet / Trade Software, crypto wallet and exchange2018 to 2019

Hired for the mobile app; within days asked to rebuild the platform. Led wallet and exchange architecture (order-book consistency on Firebase transactions), code review, hiring and releases for a platform holding about US$2M in custody. Ran its orderly decommissioning in Dec 2019.

Earlier2008 to 2018

Lenarge, Business Analyst (2013 to 2016): built the first driver hours-of-service system after Brazil's Driver Law, proposed and led the Driver Monitoring department, reporting to the legal directorate, and promoted the successor who took over the role; built Fleet OK, a Volvo Dynafleet telemetry app behind the company's driver fuel-efficiency rewards.
Co-founder: MedBit (2017 to 2018, AI symptom triage, Biominas BioStartup Lab); Gamefik (2017 to 2020, gamification for schools); Tech2N (2016 to 2017, freight marketplace, S2 geospatial). Founder: Agência Selo (2008 to 2010, web agency).

Community, open source, education

Founded Firebase BH (2017 to 2018, 130+ members); talk "Unlock realtime mode in your apps", The Developers Conference 2023. Public code: async-task-runner-js (TypeScript, 2025), cordova-plugin-firebase-native (2017), firefunctions CLI.
Information Systems, Universidade Federal de Minas Gerais (UFMG), 2012 to 2015. Portuguese (native), English (fluent).