Jeffrey Sánchez
Fullstack & Go Engineer → AI Systems Architect
Distributed Systems · LLM Integration · MLOps
Turning infrastructure into intelligence
12+Years of experience
10+Companies worked with
8+Languages & stacks
About
12 years in. Today I'm scaling RPC services to 2.9M peak QPS with 50% compute savings and building AI agents that help engineers debug production systems before the next incident hits.
The stack changed. The obsession didn't.
I'm a Go & Python engineer with a fullstack background, now focused on the intersection of high-performance distributed systems and applied AI. I refactored blocking calls into goroutine pipelines for 35% throughput gains, and shipped an Oncall Agent using LLMs and vector databases to correlate error logs with code locations and surface root causes automatically.
What I've shipped across 12 years and 10+ companies
- Scaled systems to 2.9M peak QPS with 50% compute savings and 30% latency reduction
- Architected AI agent orchestration services with LLMs for real-time intent detection
- Led monolith-to-microservices migration on AWS using FastAPI, Docker, and K8s
- Built a full ETL data lake with Dagster feeding Power BI dashboards for a K-12 education client
- Rewrote 30+ stored procedures at a major bank, cutting transaction time ~45%
- Mentored 6+ engineers and established CI/CD and code review standards across multiple teams
- Promoted to Senior within my first year, twice
Tech I think in
LanguagesGo · Python · C# · TypeScript
FrameworksFastAPI · React · React Native · Node.js · .NET MVC
AI / MLLLM APIs · RAG · Pipecat · TensorFlow · Vector DBs · Genesys Cloud AI
DatabasesPostgreSQL · MongoDB · Redis · SQL Server
InfraDocker · Kubernetes · AWS · CI/CD · Git · Bash
ObservabilityGrafana · Loki · Prometheus
ToolsgRPC · REST APIs · WebSockets · Linux · Bash scripting
The next chapter I'm actively building
- 2026 LLM APIs + Cloud-native AI systems
- 2027 MLOps · AI Security · Autonomous Agents
- 2028 Lead hybrid human-AI engineering teams
- 2029+ AI-First Systems Architect
The engineers who will matter most in the next 5 years aren't the ones who write the most code, they're the ones who architect systems that are fast, resilient, and intelligent. That's the engineer I'm becoming.
Experience
Software Go Engineer
Bitget · Remote · Contract
Jul 2025 – Apr 2026
- Optimized core RPC services handling 2.9M peak QPS, achieving 50% compute resource savings and 30% latency reduction, conducted thorough staging/production testing and traffic diversion.
- Improved system throughput by ~35% by refactoring synchronous blocking calls into concurrent goroutine pipelines.
- Enhanced on call efficiency for Wallet services by developing AI driven analysers and auto conclusion features in the Oncall Agent, used Golang, LLMs, and vector databases to rank relevant events, correlate error logs with code locations, and suggest root causes, reducing engineers' on call burden.
GolangMySQLRedisRabbitMQDockergRPCAWSGit
Senior Software Engineer
Arajet · Santo Domingo, DO · Hybrid
Feb 2025 – May 2025
- Boosted data processing throughput 3× by designing parallel Python pipelines that extracted, transformed, and loaded high-volume operational data into Azure Data Lake, cutting nightly batch windows from hours to minutes.
- Standardized the development framework and architecture, contributing to the core of new.arajet.com and establishing reusable patterns (CI/CD, code review, branching) that increased team velocity by 25%.
- Mentored six developers on clean code, test automation, and Azure DevOps best practices, accelerating their onboarding and fostering a culture of shared ownership and continuous integration.
PythonC#ReactRPAAKSDockerAzure DevopsGit
Senior Software Engineer – Freelance
Upwork · Remote
Oct 2023 – Feb 2025
- GNS – AI Consultant: Designed full observability stack with Grafana, Loki and Prometheus, architected AI agent orchestration services with Python/FastAPI for real‑time intent detection with Pipecat.
- CRECER LAB : Led backend architecture design for core product features focused on performance and scalability. Mentored junior developers, established code review standards and CI/CD workflows.
- ANTILLEAN SOFTWARE : Led migration from legacy monoliths to microservices using FastAPI/Alembic, spearheaded AWS deployments. Managed PostgreSQL migrations and centralised log management with MongoDB. Enhanced UI design and performance across web applications.
PythonFastAPIGrafanaLokiPrometheusPipecatGenesys CloudDockerKubernetesAWSPostgreSQLMongoDBGit
Software Engineer → Senior UI Software Engineer ↑ promoted
CBORD · Ithaca, NY · Remote
Jun 2021 – Aug 2023
- Led migration from AngularJS to Angular 12+, refactoring legacy components and cutting UI bundle size by 40%, which accelerated page loads and improved developer productivity.
- Enhanced Ionic mobile app UX with RxJS and built Jasmine/Protractor test suites, raising code coverage from 45% to 85% and catching regressions early.
- Implemented XSS/CSRF security hardening across the app and optimized C#/.NET SQL stored procedures, reducing average response time by 30% for order management.
AngularIonicRxJSSassTypeScriptC#.NET 4.5+MVCSQL ServerAWSBitBucketjQueryGit
Senior Software Engineer
Ed-Fi Alliance · Austin, TX · Remote
Sep 2022 – Jul 2023
- Led development of the API to AMT Data Lake an open source ETL pipeline that extracts all Ed Fi ODS API data into JSON and Parquet, shaped to match the Analytics Middle Tier for Power BI consumption.
- Orchestrated parallel data ingestion with Dagster, leveraging configurable multi CPU processing for high throughput API pagination.
- Implemented descriptor mapping engine to normalise Ed Fi ODS enumeration variability across installations, enabling consistent AMT view filtering.
PythonC#DagsterGitHubPostgreSQLPL/SQLPower BIDockerCI/CDBashJupyterGit
Software Engineer
ABI Document Support Services · Phoenix, AZ · Remote
Aug 2017 – Oct 2019
- Delivered document management and billing modules with C#, .NET MVC, and Angular, serving 200+ users and cutting paperwork time by 60%.
- Managed full lifecycle delivery, translating business requirements into technical specs and ensuring on-time releases through direct stakeholder collaboration.
- Wrote clean, testable code, integrated unit/UI tests cutting defects by 40%, and optimized SQL Server stored procedures, speeding reports by 50%.
AngularC#.NET MVCSQL ServerReactive ProgrammingAzure DevopsGit
Full Stack Engineer
MEDS Gravitas · Santo Domingo, DO
Jan 2017 – Jun 2017
- Led the integration of a physical point-of-sale system with the Odoo ERP backend, building a GraphQL API layer that synchronized inventory, sales, and customer data in near real time, reducing manual data entry errors by 70%.
- Developed real-time dashboards and notification features using React, Node.js, and Redis Pub/Sub, enabling store managers to monitor sales performance and stock levels instantly across multiple locations.
- Designed and implemented a comprehensive test suite with Pytest, achieving over 90% backend code coverage and establishing a continuous integration pipeline that reduced post-deployment issues by 50%.
PythonNode.jsReactGraphQLRedisMongoDBPostgreSQLPytestGitHubGit
Software Engineer
Citibank · Santo Domingo, DO · On-site
Feb 2015 – Nov 2016
- Rewrote 30+ stored procedures, functions, and jobs cutting transaction time ~45%, migrated apps to async/await.
- Automated processes from application layer to server, significantly improving data indexing performance.
- Drove team adoption of modern .NET patterns and async/await across the codebase.
C#WinFormsSQL Serverasync/await.NETAzure DevopsGit
Junior Software Developer
Contraloría General de la República Dominicana · On-site
Jan 2013 – Dec 2014
- Built internal government applications in C#/.NET and WinForms that automated financial control and auditing workflows, replacing spreadsheet-based processes and reducing month-end reconciliation time by 30%.
- Wrote and optimised SQL Server stored procedures for complex reporting modules, tuning indexes and query plans that accelerated report generation from minutes to under 10 seconds for millions of records.
- Participated in full lifecycle development from requirements gathering to deployment, collaborating with senior auditors to ensure the applications met legal and regulatory standards for public sector accountability.
C#WinFormsSQL Server.NETGit
Education
Bachelor of Engineering in Systems Engineering
Universidad Nacional Pedro Henríquez Ureña (UNPHU)
Associate's Degree Software Developer
ITLA · Santo Domingo, DO
Certifications
gRPC [Golang] Master Class: Build Modern API & Microservices
Udemy · Issued Aug 2025
Go Bootcamp: Master Golang with 1000+ Exercises and Projects
Udemy · Issued Feb 2025
AWS Certified Machine Learning Specialty 2025 – Hands On!
Udemy · Issued Jan 2025
Data Science: Deep Learning and Neural Networks in Python
Udemy · Issued May 2023
Machine Learning, Data Science & AI Engineering with Python
Udemy · Issued Jan 2023
Introduction to Redis for AI
University.redis.io · Issued Jan 2025
Next.js 15 & React – The Complete Guide
Udemy · Issued Jun 2022
React – The Complete Guide 2025 (incl. Next.js, Redux)
Udemy · Issued Apr 2022