Tim Joseph Dumol

Full-Stack Developer, SRE, Data Engineer

[email protected] Spain

Summary

A performance-driven engineer with extensive experience in full-stack web development, Site Reliability Engineering (SRE), Data Engineering, and productionization of AI/LLM features. I leverage a deep background in mathematics and competitive programming (won national and international contests in algorithms & data science) to design and implement robust, scalable, and highly efficient systems. I thrive on solving complex problems within their business context, ensuring technical solutions are pragmatic, secure, and aligned with strategic goals. I have extensive experience mentoring engineers in SRE, AI, and algorithms, and co-founded the Philippines' national informatics olympiad.

Experience

Principal Software Engineer Expedock | Dec 2023 - Present

Founding Engineer Expedock | May 2020 - Dec 2023

  • Translated vague business requirements into concrete technical solutions, personally coding across the full stack while leading and mentoring engineers.
  • Prioritized rapid shipping and iteration cycles to gather user feedback early, enabling quick pivots and continuous product improvement.
  • Re-engineered a bottlenecked Python microservice in Rust, fixing availability issues and enabling processing of ~1k requests/second.
  • Improved performance and cost-efficiency of AI features while measuring actual business impact instead of vanity metrics.
  • Set up automated sales call transcription and tagging via LLMs to help monitor and improve sales performance.
  • Integrated CI/CD, analytics tools (Posthog), and observability systems (Prometheus, Grafana).
  • Performed regular cloud cost monitoring and optimization, implementing targeted improvements that saved 90% on PostgreSQL-to-Snowflake CDC costs and 40% on compute infrastructure
  • Trained engineers in applications and limitations of AI - how to best leverage AI in their daily workflow while understanding its limitations due to its mathematical foundations, as well as how to integrate AI in applications

Skills

  • Python
  • TypeScript
  • Kubernetes (GKE and EKS)
  • AWS
  • GCP
  • Snowflake
  • PostgreSQL
  • React
  • GraphQL

Projects

Strawberry SQLAlchemy

Created and open-sourced an integration for strawberry-graphql with SQLAlchemy for automatic efficient loading of relationships, without N+1 query issues.

Volunteering

Corporate Secretary & Treasurer

National Olympiad in Informatics - Philippines

2017 - 2020

Co-founded the Philippines' national qualifier for the International Olympiad in Informatics. Coordinated the scientific committee, wrote contest problems, and trained delegates in algorithms and data structures.

Data Infrastructure Engineering Lead Kalibrr | Jun 2019 - Jun 2020

  • Created the Data Infrastructure team to maximize AI team productivity and enable data access for stakeholders.
  • Spearheaded ingestion of internal data into a BigQuery data warehouse, reducing analysis time in some cases from days to minutes (>100x improvement).
  • Streamlined ML model productionization with a standard spec-first template and Helm chart, improving ML development velocity 6x (from 1 model/year to 1/two months).
  • Improved observability of ML models by incorporating error reporting, distributed tracing, and Prometheus metrics into the standard template.

Site Reliability Engineering Lead Kalibrr | Sep 2017 - Jun 2019

  • Led migration to Kubernetes from VPSes, enabling autoscaling and reducing new instance provision time from hours to minutes.
  • Set-up and managed a self-hosted PostgreSQL cluster (with daily backups and PITR), saving 50% over GCP-managed.
  • Introduced SRE principles and started the SRE team, and trained the SRE team using codelabs and scenario simulations.
  • Optimized various endpoints by up to 1000x via Python and PostgreSQL profiling.
  • Reduced GCP bill by 50% through a focused cost optimization project.

Chief Software Engineer Kalibrr | Aug 2013 - Sep 2017

  • Built and maintained core features across the stack, focusing on reliability and clear analytics.
  • Set-up CI/CD for rapid deployment and testing.
  • Set up monitoring and alerting to quickly catch and resolve issues, improving uptime.
  • Improved candidate matching by setting up observability for performance and accuracy, and iterating based on those metrics.
  • Oversaw architectural decisions, provided technical leadership, and ensured the platform's reliability, stability, and performance.

Developer Sage Open Source Mathematics Software | 2009 - 2011

  • Contributed to the Sage Notebook web UI (notebook-based UI for Python before Jupyter/IPython Notebook) for the open-source SageMath project.
  • Worked on migrating the old architecture to an independent package, including numerous bug fixes and template migrations.

Honors & Awards

1st place, Trend Micro Codinsanity 2014
Data Science (Latent Dirichlet Allocation, Customer Segmentation)
Technical Excellence, Manila Game Jam 2013
Game Development
Bronze prize, ACM ICPC Asia-Hanoi Regionals 2012
Competitive Programming
1st place, ACM ICPC Philippines Invitational 2013
Competitive Programming

Languages

  • English (Native)
  • Filipino (Native)
  • Spanish (A2, Studying)

Education

Bachelor of Science, Mathematics (magna cum laude)

University of the Philippines Diliman | 2010 - 2014