Ismael Marin

Software Engineer & Tech Lead

León, Guanajuato, Mexico · Remote

Email: ismael.marin@gmail.com

Phone: +52 477 792 9000

Website: ismaelmarin.dev

LinkedIn: in/ismaelmarin

GitHub: github.com/igmarin

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Professional Summary

Software engineer and technical leader with deep experience building backend systems, SaaS products, integrations, and engineering teams for U.S. and Latin American companies. Ruby on Rails is my deepest production ecosystem, while I now work regularly with Rust, Elixir/Phoenix, and Python, particularly around developer infrastructure and AI systems. I approach AI as a software engineering problem: clear specifications, useful context, tests, guardrails, and evals. I have worked remotely throughout my career and remain hands-on with architecture and implementation.

Core Skills

Software Engineering

Ruby on Rails, Rust, Elixir/Phoenix, Python, PostgreSQL, Redis, Sidekiq, REST APIs, OpenSearch, AWS, Docker.

Architecture & Systems

Software architecture, distributed systems, DDD, hexagonal architecture, monolith design, API design, TDD, BDD, SOLID.

AI Engineering

MCP, LLM integration, AI agents, evals, context engineering, guardrails, RAG, multi-provider LLM systems, local models.

Leadership & Product

Technical leadership, engineering management, product strategy, technical discovery, MVP development, mentoring, ADRs/RFCs.

Professional Experience

Head of Strategy / Technical Advisor · Nebula Ideas

2010–Present · Remote · Mexico / United States

Advise startups and product teams on architecture, backend modernization, AI adoption, technical strategy, and product development while remaining hands-on with implementation.
Build and modernize Ruby on Rails products, infrastructure, APIs, and e-commerce systems; help founders define MVP scope, technical priorities, and architecture appropriate to product stage.
Apply a pragmatic architecture approach: strong boundaries where complexity requires them, and simpler designs where speed, cost, and learning matter more.
Develop AI engineering and developer tooling across Ruby, Rust, Elixir, and Python.

Software Engineer → Senior Software Engineer → Tech Lead · Dealerware

May 2022–April 2026 · Remote · U.S. SaaS

Promoted from Software Engineer to Senior Software Engineer and then Tech Lead while remaining an active contributor across a large Rails ecosystem.
Led technical work for an integrations-focused team, collaborating with backend engineers, QA, DevOps, product, and external partners.
Worked on distributed systems processing approximately 10,000 telematics events per minute and on integrations supporting vehicle lifecycle and daily operational workflows.
Architected and implemented Auth0-based enterprise identity and SSO integrations, plus role-aware analytics integrations with Databricks and ThoughtSpot.
Led a zero-downtime Elasticsearch-to-OpenSearch migration that materially reduced infrastructure cost while preserving production availability.
Redesigned legacy vehicle classification logic to support multiple manufacturers, VIN-derived trim validation, and richer vehicle classification.
Authored 40+ ADRs/RFCs and contributed 370+ merged pull requests across 20+ production repositories.

Lead Software Engineer · 3Pillar Global

September 2020–October 2021 · Remote

Designed an end-to-end internationalization architecture spanning backend, frontend, and third-party integrations.
Modernized legacy Rails systems using clearer domain boundaries, service objects, and automated testing; worked on REST APIs and performance-sensitive distributed services, including Go components.

Lead Software Engineer · United Virtualities

August 2019–August 2020 · Remote

Led projects from technical discovery and architecture through implementation and AWS production deployment across e-commerce, startup MVP, and web application engagements.
Served as technical lead and client-facing engineering contact, balancing architecture, delivery timelines, budgets, and evolving requirements.

Tech Lead, B2B · Reservamos / reserhub

August 2018–August 2019 · Remote

Helped create and grow the B2B product area and designed integrations between enterprise transportation partners and the Reservamos platform.
Led cross-functional delivery of white-label products and partner integrations, working directly with customer technology teams on APIs and implementation approaches.

Staff Engineering Manager / Lead Engineer · MagmaLabs

February 2016–August 2018 · Remote

Progressed through three leadership levels; oversaw delivery across customer projects through Engineering Managers / Project Managers and acted as an escalation point for delivery and customer concerns.
Coordinated with Sales when technical work exposed expansion opportunities and led engineering work across Rails e-commerce systems, Spree/Solidus, payments, subscriptions, and international checkout workflows.
Helped run the Hacker Academy mentoring program for 30+ early-career engineers and owned hiring, mentoring, 1:1s, career development, and engineering quality across teams.

Open Source & AI Engineering

rails-ai-bridge: MCP and context infrastructure that lets AI coding assistants understand real Rails applications through generated project context and read-only introspection.
ruby-skill-bench: evaluation framework for measuring whether engineering skills and additional context improve AI-agent performance using isolated runs, baseline-versus-context comparison, and blind judging.
rails-agent-skills / ruby-core-skills: engineering skill libraries covering Rails, Ruby, testing, refactoring, architecture, security, and development practices for coding agents.
Rust tooling, including rs-guard, focused on local and CI execution, agent workflows, persistent context, and memory-safe CLI systems.
Elixir/Phoenix skills covering Phoenix, LiveView, Ecto, architecture, and agent-assisted development.

Mentoring & Engineering Development

The Hybrid Group: mentored engineers transitioning into Ruby development and progressing toward senior-level responsibilities through code review, technical guidance, and structured growth.
MagmaLabs Hacker Academy: helped guide a cohort of 30+ recent graduates and early-career developers, with selected participants moving into full-time engineering roles.

Education & Languages

Graduate Studies in Information Technology — ITESO, Jesuit University of Guadalajara · 2005–2007
B.S. Information Technology & Business Administration — UNIVER León · 2002–2005
Spanish (Native) · English (C1 professional proficiency)

Technical Writing & Public Communication

Technical writer on software architecture and AI engineering at Medium; regular contributor on AI adoption and its limits for Radio Fórmula.

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