Software engineer · New York

Adelson
Aguasvivas.

I build software end to end.

Four-plus years building secure, data-intensive systems at scale, from petabyte pipelines at Amazon to platform engineering at Coachable. Harvard CS, 2021.

After hours: games, tools, and two dominoes apps on the App Store.

Email Resume GitHub ↗ LinkedIn ↗

55 PB

of Alexa data covered by deletion and retention workflows

$1.3M

in quarterly savings from S3 lifecycle automation

200+

students coached in CS fundamentals and interview preparation

12+

independent projects across systems, mobile, and games

iPhone apps published on the App Store

Experience

Download resume (PDF) ↓

May 2023 · Present · New York, NY

Coachable · Software Engineer

Platform, analytics, and internal tools for a coaching program serving 80+ active learners.

Built and scaled the platform and data systems used by 80+ learners in a program with a 95% placement rate.
Designed analytics pipelines for learner performance and hiring outcomes, making reporting 3x faster and improving data accuracy by 40%.
Built Python, React, and AWS tools that improved operating efficiency by 50%, including LLM-assisted résumé workflows.
Coached 200+ engineers in CS fundamentals and conducted 1,000+ mock interviews, contributing to hundreds of offers.

July 2021 · January 2023 · Cambridge, MA

Amazon · Software Development Engineer, Alexa

Privacy, security, and storage systems for Alexa at petabyte scale.

Led data deletion and retention across 700M+ objects and 55 PB of S3, saving $1.3M quarterly through lifecycle automation in Python and Java.
Security Lead for the team: resolved 80+ risks, including 25+ high-risk issues and 2 critical org-wide escalations, through IAM hardening and encryption enforcement.
Owned GDPR and CCPA deletion jobs across petabyte-scale datasets with zero compliance violations.
Resolved 300+ on-call tickets at a 99.9% SLA and improved recovery time by 40%.

Summer 2019 · Urbana-Champaign, IL

University of Illinois Urbana-Champaign · Research Engineer, DREU Program

Summer research on automated feedback for large computer science courses.

Built an automated grading and hint-generation system for large CS courses with LLVM, C/C++, and Python: 10x grading throughput.
Selected as one of roughly 40 students nationally for the DREU research program.

2017 · 2021

Harvard University · A.B. Computer Science, 2021

Secondary in Ethnicity, Migration and Rights. Spanish citation.

Honors: Forbes 30 Under 30 Scholar · HSF Scholar · Tuskegee Airmen Scholar · NSA Scholar · Dominican Day Parade Scholar

Selected work

Systems, products, and games I have taken from idea to working software, with the architecture and tradeoffs behind each.

Ledgerline

Live

An edge-native event-stream API built around idempotent appends, ordered streams, and SHA-256 tamper evidence.

Idempotency keys retained for a stream’s lifetime replay the original append result
A canonical SHA-256 chain verifies the log and detects edited or truncated history
69 tests run in the Workers runtime with Durable Objects and local D1

Cloudflare WorkersDurable ObjectsD1TypeScriptHono

The Cap Room

Live

An NBA front-office console for cap sheets, explainable two-team trade checks, and player evaluation.

A pure TypeScript engine models 2023 CBA trade rules with zero UI imports and 44 tests
The Rule Ledger shows each check, result, and relevant salary calculation
Trade proposals serialize into the URL for reproducible, shareable scenarios

Next.jsTypeScriptReactVitest

Capi

App Store

Dominican dominoes online with your people: 1v1 or 2v2, capicúa, tranque, and no account.

A shared, zero-dependency rules engine with 112 passing tests
Real-time web and iPhone play through Supabase Realtime
Dominican table rules, quick chat, and places that feel familiar

Next.jsTypeScriptSupabase Realtime

Read more → Play ↗ App Store ↗ GitHub ↗

SWARMGEDDON

Live

A web-first survival shooter with a custom fixed-step simulation, pooled WebGL entities, and seeded Daily runs.

60 Hz simulation decoupled from rendering, with interpolation
Spatial-hash collisions and object pools support dense combat
Synthesized Web Audio, with no shipped sound files

TypeScriptPixiJSWebGLCapacitorPWA

Invicto

Live

Build a 12-slot World Baseball Classic roster across six editions, then try to finish a seven-game tournament undefeated.

Wikipedia rosters joined to SABR Lahman data and validated before release
Monte Carlo calibration keeps a 7-0 run rare for an elite reference lineup
Four locales and anonymous daily stats on Cloudflare D1

TypeScriptViteCloudflare D1

Anota

App Store

A Dominican dominoes scorekeeper for iPhone, built for the two-team table.

Live on the App Store with Pro and Remove Ads purchases
Both teams, score history, and controls stay on one screen
Capicúa presets, haptics, bilingual UI, and shareable final-score cards

ExpoReact NativeTypeScriptStoreKit

How I build

The engineering habits that show up in every project I own.

Test the system that ships

Ledgerline runs 69 tests in workerd, Capi’s engine runs 112, and Conuco’s core runs 126. I want tests to exercise the real system, not an approximation of it.

Deterministic by design

Gameplay randomness flows through seeded generators, so the same seed reproduces the same simulation. That keeps daily challenges fair and makes bugs reproducible.

Calibrate, don’t guess

Invicto uses Monte Carlo simulation to keep a perfect 7-0 run in the intended 2 to 5% band. The test suite catches balance drift before it ships.

Design saves for change

Conuco uses versioned saves, additive migrations, defaulted fields, and backups. Older save files can move forward safely as the game evolves.

Bilingual by construction

English and Spanish dictionaries share one enforced type, so missing or mismatched copy fails the build instead of becoming a bug report. This site works the same way.

AI at the edges, engines at the core

The System uses models for résumé analysis and drafting. Deterministic code owns scheduling, document structure, and fallbacks, keeping the workflow predictable even when the API is unavailable.

After hours

Outside work, I make games and small tools. Four are live in the browser.

Play now

SWARMGEDDON

A web-first survival shooter with a custom fixed-step simulation, pooled WebGL entities, and seeded Daily runs.

▶ Play →

Invicto

Build a 12-slot World Baseball Classic roster across six editions, then try to finish a seven-game tournament undefeated.

▶ Play →

Flawless

Draft five anime characters and survive a seven-battle tournament, delivered in an approximately 80 kB gzipped gameplay payload.

▶ Play →

Capi

Dominican dominoes online with your people: 1v1 or 2v2, capicúa, tranque, and no account.

▶ Play →

Free to play in the browser, with no account required.

El Corre Corre

App Store soon

A one-thumb Dominican arcade ride through the Malecón, where en contra vía doubles the score.

Oncoming traffic gets a 1.5-second telegraph based on closing speed
Traffic spawns check for a usable corridor before entering the road
A live Web Audio dembow score responds to the run, with no audio files

TypeScriptThree.jsViteCapacitor

The Veil · El Velo

Private build

A playable Rawls experiment: write six social policies, then live through the outcomes they create.

A headless model evaluates each ruleset before the interface presents it
Tests validate that the designed model rewards balanced rulesets over its two extremes
Spanish-first React experience, with native configuration through Capacitor

ReactTypeScriptZustandCapacitor

Conuco

Private build

A Caribbean farming and fishing game about helping a coastal pueblo come back to life.

A renderer-independent game core with 126 passing tests
Seeded play, versioned saves, additive defaults, and a backup save
Dominican terms stay intact across Spanish and English

TypeScriptPixiJSVitestCapacitor

More projects

More experiments, tools, and work still in progress.

The System

Private build

A private job-search cockpit with deterministic prep planning and structured AI assistance.

ReactViteClaude APITailwind

Living Todo OS

Private build

A private planning system that helps choose the next realistic action.

Next.jsTypeScriptClaude APITailwind

Flawless

Live

Draft five anime characters and survive a seven-battle tournament, delivered in an approximately 80 kB gzipped gameplay payload.

TypeScriptViteCloudflare Workers

Play ↗ GitHub ↗

Coherente · Bite the Bullet

In development

A work-in-progress roguelike of moral consistency. You do not lose for being wrong, only for contradicting yourself.

ReactTypeScriptZustand

Hype Room

In development

An M1 iOS storefront prototype for a real sneaker shop, with drops, catalog browsing, and a swappable data layer.

ExpoReact 19TypeScript

Earlier work

About

I studied computer science at Harvard, then spent two years at Amazon building privacy and data-retention systems for Alexa across 55 petabytes of data. Today I’m at Coachable, where I build the platform, analytics, and internal tools used by learners and coaches.

I’m Dominican and grew up between Spanish and English. That shapes how I build: bilingual interfaces by default, and projects with a piece of home in them, from dominoes and baseball to the Malecón and the conuco.

I build outside work because I like following an idea through the full product cycle, from the engine and data model to the details someone feels on screen. It keeps me sharp, and honestly, it’s fun. Recent releases include two iPhone apps and several browser games.

Get in touch

Want to discuss a role, a project, or the engineering behind this work? Email is the best way to reach me.

Send an email Resume

adelsonaguasvivas@gmail.com

GitHub ↗ LinkedIn ↗

AdelsonAguasvivas.

Experience

Coachable · Software Engineer

Amazon · Software Development Engineer, Alexa

University of Illinois Urbana-Champaign · Research Engineer, DREU Program

Harvard University · A.B. Computer Science, 2021

Selected work

How I build

Test the system that ships

Deterministic by design

Calibrate, don’t guess

Design saves for change

Bilingual by construction

AI at the edges, engines at the core

After hours

SWARMGEDDON

Invicto

Flawless

Capi

More projects

The System

Living Todo OS

Flawless

Coherente · Bite the Bullet

Hype Room

Earlier work

About

Get in touch

Adelson
Aguasvivas.