Currently @ Clara — open to interesting roles

Diego Salas.
Fullstack Engineer.

Engineering products end-to-end — from API design and data models to performant, accessible interfaces.

Get in touchDownload CV

01 — About

A pragmatic engineer who ships.

I'm a Fullstack Engineer with 6+ years of experience shipping production software across fintech, healthcare and logistics. I currently build internal platforms at Clara using React, TypeScript, Java, Spring Boot, AWS and PostgreSQL. I care about clean APIs, tight feedback loops, and software that holds up under real-world load.

I gravitate toward problems at the intersection of frontend, backend and data — designing the contract, building both sides, and shipping something that works end-to-end. I've done this across fintech, healthcare, logistics and edtech.

Based in
Pachuca de Soto, MX
Languages
Spanish (native), English (professional)

02 — Experience

Where I've built things.

Highlights from the last 6+ years. Stacks change; the bar for shipping doesn't.

  1. Fullstack Engineer @ Clara

    Nov 2022 — Present

    Remote — LATAM

    Building internal platforms used daily by operations, finance and compliance teams at a YC-backed fintech serving thousands of businesses across LATAM.

    • Designed and shipped backend services in Java/Spring Boot exposing REST APIs consumed by both internal tooling and customer-facing apps.
    • Owned end-to-end features spanning React/TypeScript frontends, PostgreSQL schemas, AWS infrastructure and observability.
    • Built Retool-based internal tools that replaced manual ops processes, cutting resolution time on multi-step workflows.
    • Worked closely with product, design and compliance to translate ambiguous requirements into reliable, well-tested systems.
    ReactTypeScriptJavaSpring BootPostgreSQLAWSRetool

  2. Lead Frontend Engineer @ Zenda.la

    Oct 2021 — Nov 2022

    Mexico City, MX

    Led frontend architecture for a health insurance web platform — from policy purchase flows to the member dashboard.

    • Architected the Next.js + TypeScript codebase, defining patterns for routing, state, forms and analytics that the team scaled on.
    • Integrated Segment, GTM and GA across the funnel to power growth and conversion analytics.
    • Mentored frontend engineers through code reviews and pairing, raising the bar on typing, testing and accessibility.
    Next.jsReactTypeScriptMUIReduxStyled ComponentsGhostSegment

  3. Fullstack Developer @ Lapzo

    May 2021 — Oct 2021

    Remote

    Built a corporate training platform end-to-end: from PostgreSQL schemas and Hasura/GraphQL APIs to the React + TypeScript client.

    • Modeled relational data for courses, cohorts and progress tracking; exposed it via Hasura with row-level permissions.
    • Implemented authenticated React/TypeScript client with role-aware UI and real-time progress updates.
    ReactTypeScriptExpressHasuraGraphQLPostgreSQL

  4. Frontend Developer @ Sodisa

    Oct 2020 — Apr 2021

    Mexico

    Modernized an internal logistics system used to coordinate freight operations across the company.

    • Migrated legacy screens to a Next.js + TypeScript stack with CSS Modules and a shared component library.
    • Partnered with ops to redesign workflows that reduced data-entry friction for daily users.
    Next.jsReactTypeScriptFigmaCSS Modules

  5. Software Developer & Lead Instructor @ Actosoft

    Jun 2019 — Dec 2022

    Hidalgo, MX

    Built frontends for client projects while leading the community's frontend curriculum and teaching cohorts of new developers.

    • Designed and delivered a hands-on React/TypeScript curriculum that produced multiple junior hires.
    • Shipped frontend features across client projects using React, Firebase and Styled Components.
    JavaScriptTypeScriptReactFirebaseSASSStyled Components

03 — Selected work

Things I've shipped.

A few projects that capture how I approach problems end-to-end.

Enlonados

Dashboard and ops tooling for a tarp manufacturing business, replacing spreadsheets with a typed data model and real-time views.

Problem & approach. The business tracked orders, inventory and production in disconnected spreadsheets. I designed the Postgres schema in Supabase and built a Vite + React + TypeScript dashboard so operators could see live status and reduce hand-offs.

ReactTypeScriptViteTailwindPostgreSQLSupabase

Posiffy

Multi-tenant SaaS POS for small retail businesses, with role-based access, inventory and sales reporting.

Problem & approach. Designed the data model for a multi-tenant POS — products, variants, stock, sales, users — and built it with Next.js, Redux and Supabase. The challenge was scoping every query to the active tenant cleanly while keeping the UI fast.

Next.jsReactTypeScriptTailwindReduxSupabasePostgreSQL

More than Books

Content-driven marketing site for a book club, built on Next.js with Strapi as a headless CMS.

Problem & approach. Needed a site where non-technical staff could publish content without touching code. Modeled content types in Strapi and rendered them through Next.js with ISR for fast, SEO-friendly pages.

Next.jsTypeScriptTailwindStrapi

Save365

Personal finance app for tracking expenses, budgets and savings goals with a typed Redux store and Firebase backend.

Problem & approach. Wanted a personal finance tool that matched my budgeting flow. Built it with React + Redux Toolkit + TypeScript and Firebase, focusing on offline-friendly data sync and clean, fast UX.

ReactTypeScriptRedux ToolkitStyled ComponentsFirebase

04 — Stack

What I work with.

Tools I reach for daily. I'm pragmatic — the right stack is the one that fits the problem.

Languages

TypeScriptJavaScriptJavaSQL

Frontend

ReactNext.jsTailwind CSSRedux ToolkitAstroStyled Components

Backend

Node.jsSpring BootExpressGraphQLREST APIs

Database

PostgreSQLSupabaseFirebase

Cloud & DevOps

AWSVercelDockerGitHub Actions

Tools

GitFigmaRetool

05 — Contact

Let's talk.

Have a role, a project, or an interesting problem? Drop me a line.

Email

hola@diegosj.com

LinkedIn

juan-diego-sj

GitHub

Diego-SJ

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