Guilherme Martins
Portfolio Images
Welcome to my portfolio page. My name is Guilherme Martins (pronounce: gee-le-AIR-me), I’ve recent experience working as:
- Full-Stack Software Engineering
- Platform Engineering
- Data Engineering
I worked for:
| Company | Role | Description |
|---|---|---|
| CRSP Center for Research in Security Prices (Acquired by Morningstar) | Cloud and C#/Python/Typescript/SQL Software Engineering | Market Indexes and RDP Research Data Products. Finance data generation for tracking ~$3 trillion dollars in AUM |
| DSI Data Science Institute) | Data Engineering, Full Stack and Infra Orchestration | Advanced collection, processing and analysis of Internet performance data, supporting high speed internet fund allocation decisions. |
| Princeton University / Georgia Tech | Tools and Data Platform engineering | Development of Internet Performance Measurement tools and data engineering of telemetry data. |
| Alcatel-Lucent | Network Software Engineering | Network Traffic Control and Detection Intelligence |
Highlighted Achievements:
- CRSP: I worked as Market Indexes dev team member responsible for CRSP’s largest code base migration in C# (470k lines).
- CRSP: While at CRSP worked on stories updating and refactoring code spanning from IaC (pulumi), SQL store procedure, C# API to Angujar/Typescript
- CRSP I led a SDET squad and produced the CRSP’s first CLI containing automation responsible for saving hours of manual QA and DevEx procedures.
- DSI: I worked as a Netrics project leader developing the backend responsible for producing 1 billion data points
- DSI: I developed the backend API, front engines and analytics of a customer-facing workflow for beadchallenge dot org helping unserved/underserved status claims across Illinois.
- PU/GATech: I designed and developed the network capture tool used to produce ground-truth data for advanced Machine-Learning inference on network traffic classification.
- ALU: Main responsible of the CloudShield network traffic control code base (core part of the Agya Solution), have worked on network traffic processing optimizations.
Instead of a wordy cv/resume, here’s a more relaxed collage of images with important documentation of my work, as most of it is open source. Disclaimer: Some conclusions here are my own.
| Projects | Description |
|---|---|
| Netrics Backend. DSI. In my responsibility for 3 years, in prod it crossed the 1 billion data-point mark of encrypted data. The stack includes a Golang data collection application, Python and Terraform IaC, SQL database, parallel Python data ingestion, Kafka producer/consumers. On the right, is the System Design for beadchallenge dot org |
Figure 2. Aggregated average latency (active unloaded ICMP) for regions in Chicagoland (all Netrics deployed devices). Data warehoused on TimescaleDB, image extracted from Superset BI tool. Estimated devices deployed: 120 in Chicago area (initial sample size). We benchmark the internet for ISPs to ensure internet consumers are getting a fair performance from their contracted services and understand any significant differences between regions. Note: fiber technology with superior performance (low latency) compared to the rest.
Figure 3. A Netrics Grafana dashboard with fluctuation on both latency and throughput. Note: fluctuations and wifi bottleneck/constriction negligible to normal internet user's perception. Research question TBD: How much "power" internet users, like high performance game players or day traders, can tolerate of internet performance impairments like this.
Figure 4. Campus deployment of Netrics, showing high latency for an outlier (Booth School). Image extracted from Looker Studio.
Figure 5. BEADChallenge.org analytics, where the internet speeds are lower (unserved/underserved) in IL, USA? / Satellite Internet Performance: The key technology responsible for bringing Internet to unserved. (Download / Upload in Mbps).
Figure 6. Data analysis work for the Internet Equity Initiative group. Does the low-income population have worse internet performance than the high-income? What does it mean to be an underserved or unserved area regarding broadband infrastructure? Is the broadband evolving in the US (2019 - 2021 comparison)?
Video 1. First prototype of Netrics Passive in action (aka NetMicroscope). Software implemented in C with libwebsockets, libpcap, html, javascript, jquery, chartjs.
[WSJ Study](https://www.wsj.com/graphics/faster-internet-not-worth-it/)
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Figure 7. Netrics Passive Schematics developed circa 2015. A $200 kit (Jetson Nano 472 GFLOPS) for high-performance passive packet capture, network monitoring and ML inference. (Image generated with [IsomerJS]. Full source code [here].)
Figure 8. My earlier work (circa 2009-2011) on Deep Packet Inspection (DPI) for Alcatel-Lucent, programming CloudShield/IBM equipment (PacketC / C ). I was the principal engineer for the protocol/app service detection intelligence of the network traffic control engine called Agya. The solution was deployed in the Latin America region, mainly in Brazil.