Yosef Blandin · Rosario, ArgentinaLearn AI. Learn with AI.

I’m a software engineer with 5+ years shipping React, React Native, Next.js and TypeScript, the last three in payments and banking. Here I share what I learn about AI: how it works, how to use it, build with it, and think better with it.

Portrait of Yosef Blandin wearing glasses, a black turtleneck and a brown jacket
Remote (UTC-3)ES · EN

Selected work

Products I’ve built

Eight products, from aid payments in the field to a bank’s app in the stores and a VPN client built from the protocol up. Each one lists the problem, what I built and what changed.

  1. AIDONICOct 2025 – Present

    Aid-payments vendor app

    NGO vendors hand out cash and voucher aid, often with poor connectivity and in many languages. The app has to work every time.

    • Took the React Native app from 1.0 to 2.1 in nine months.
    • Shipped biometric and offline login, QR and offline-card scanning, and receipts.
    • Built a bank-transfer payout flow with OCR receipt review, behind a feature flag.
    • React Native (New Arch)
    • TypeScript
    • Next.js
    • Serverless AWS
    • Turborepo
  2. Three Bangente app screens: the home screen with accounts, the services menu, and the login screen
    Partnet GroupOct 2023 – Present

    Bangente banking app

    A bank needed its own mobile app, from the first line of code to release in both stores.

    • Built and shipped it to 500 active users with EAS Build, through major React Native and Expo upgrades.
    • Built transfers, currency exchange, QR and bill payments, cards and fixed-term deposits.
    • Added NFC tap-to-pay through a custom Expo native module and a Rust cryptography library.
    • React Native
    • Expo · EAS
    • Swift
    • Kotlin
    • Rust
    • Redux
  3. Smart Compliance dashboard with execution status bars, a risk scatter plot and stacked bar charts
    Smart ComplianceAug 2024 – Oct 2025

    Real-time compliance dashboard

    Companies track hundreds of environmental-regulation commitments and need to see risk at a glance, on a wall monitor or a phone.

    • Built a real-time, multi-chart dashboard in React and Recharts over WebSockets.
    • Cut server load with Apollo Client caching and debounce patterns.
    • Built a heat-map of 10k–20k points with D3.js force simulations, covered by Playwright tests.
    • React
    • TypeScript
    • GraphQL · Apollo
    • Recharts
    • D3.js
    • Playwright
  4. Almacén Saludable Rosario home page, with the store’s headline beside its best-selling products and the diet categories below
    Almacén Saludable RosarioJun 2026 – Present

    Health-food store on WooCommerce

    A health-food store sells about 3,500 products online, many by weight, and its ERP reads every order. The site was slow, checkout offered delivery far outside the city, and orders reached the ERP days late.

    • Cut server response from 1.7 s to about 134 ms and replaced a missing 2.9 MB hero image with a 56 KB WebP.
    • Built selling by weight and a delivery zone checked against Argentina’s official address API.
    • Traced orders reaching the ERP nine days late to two causes in 267 captured requests, and fixed both.
    • WordPress
    • WooCommerce
    • PHP
    • JavaScript
    • Docker
    • WP-CLI
  5. Three Blanarch screens: connected with a pinned certificate, connecting while it reads an emailed code, and connected in dark mode
    BlanarchPersonal product · 2026

    Android VPN client, built from the protocol up

    People whose company runs FortiGate SSL-VPN depend on an official Android client rated 3.7 stars, with drops the top complaint. They need a calm client that reconnects on its own and never trusts a certificate silently.

    • Wrote the SSL-VPN protocol stack in Kotlin from a written spec, covering sign-in, PPP negotiation and the tunnel.
    • Built the Flutter app on MVVM, with a typed Pigeon bridge, a 12-phase connection state machine and 26 typed errors.
    • Covered it with 176 tests: 120 for the Kotlin engine, 32 for view models and 24 golden screenshots.
    • Flutter
    • Dart
    • Kotlin
    • Coroutines
    • Pigeon
    • Android VpnService
  6. Filtration Advice home page for its HVAC air-filtration total-cost-of-ownership software
    Filtration AdviceClient project

    HVAC filtration monitoring

    Facilities teams need to see how their air filters perform and what they cost, from live sensor data and lab reports.

    • Built a real-time monitoring dashboard in Angular and Chart.js over WebSockets.
    • Built PDF analysis reports with pdfjs, working within its limited CSS support.
    • Built a multi-step setup form with Angular Reactive Forms and async validation.
    • Angular
    • RxJS
    • TypeScript
    • Chart.js
    • Jasmine
    • Cypress
  7. Growth Road student dashboard with a progress ring, vocational-interest charts and course chapters
    Turpial DevelopmentFeb 2022 – Sep 2023

    Client work: speed, search and dashboards

    Agency work for several clients, where speed and search directly affected traffic.

    • Cut a client site’s initial load from 8s to 1.5s, and bounce rate fell 13%.
    • Built a React pharmaceutical search that lifted traffic by about 8%.
    • Built Growth Road’s real-time student dashboard and per-student PDF reports.
    • React
    • Angular
    • TypeScript
    • SASS
    • Django
  8. Wingoo home page: “One application, thousands of jobs opportunities”, with partner logos below
    Wingoo.ioFeb 2021 – Jan 2022

    Wingoo job-matching platform

    Companies invite candidates through one registration, so nobody has to search thousands of listings.

    • Joined as the only frontend developer.
    • Led the migration from Rails views to Next.js and TypeScript.
    • Cut CSS bloat by 80%.
    • Next.js
    • React
    • TypeScript
    • SASS
    • Formik

Experience

5+ years, all remote

Product teams, an agency and a startup, working across time zones from UTC-3.

  1. Oct 2025 – Present

    Software Engineer · AIDONIC

    Vendor app 1.0 → 2.1 in 14 languages; payouts, access control and the monorepo move.

    Current
  2. Oct 2023 – Present

    Mobile Engineer · Partnet Group

    Led the Bangente banking app from code to both stores; maintaining it since Nov 2025.

    Maintenance
  3. Jun 2026 – Present

    Freelance Full-stack Engineer · Almacén Saludable Rosario

    Sole engineer on a WooCommerce store: selling by weight, delivery zones, ERP sync, 1.7 s → 134 ms.

    Freelance
  4. Aug 2024 – Oct 2025

    Frontend Engineer · Smart Compliance

    Real-time compliance dashboards over WebSockets, with a 10k–20k point heat-map.

  5. Feb 2022 – Sep 2023

    Frontend Engineer · Turpial Development

    Initial load 8s → 1.5s, pharma search +8% traffic, student dashboards.

  6. Feb 2021 – Jan 2022

    Frontend Engineer · Wingoo.io

    Sole frontend developer; Rails to Next.js and TypeScript, CSS bloat down 80%.

Full résumé on LinkedIn Platzi Frontend Developer, plus 65 certifications (2020 – 2023).

Skills

Tools I use every week

Grouped by the job they do, not by how long I’ve known them.

Languages

  • TypeScript
  • JavaScript
  • Kotlin
  • Dart
  • Swift
  • Rust
  • PHP

Web and mobile

  • React
  • React Native (New Arch)
  • Expo · EAS Build
  • Next.js
  • Flutter
  • WooCommerce
  • App Store & Google Play

Real-time and data

  • WebSockets
  • GraphQL
  • Apollo Client
  • D3.js
  • Recharts

State and UI

  • Redux
  • RxJS
  • Tailwind CSS
  • shadcn/ui

Testing and delivery

  • Feature flags
  • Jest
  • Playwright
  • TDD
  • pnpm workspaces
  • Turborepo

AI tools and open source

  • Claude Code
  • Cursor
  • Agent project skills
  • Figma MCP
  • SWC contributor (Rust)

Testimonials

What people I’ve worked with say

“One of the most exceptional developers I have ever worked with.”

I had the privilege of managing Yosef during his work as a frontend developer on our team. Without hesitation, I can say that he stands out as one of the most exceptional developers I have ever worked with.

His dedication and professionalism were evident in the two key projects he contributed to, namely ‘Nsur’ and ‘Snap’. Not only did Yosef consistently deliver his work punctually, but he also took the initiative to propose and execute performance enhancements for our websites.

Beyond his technical expertise, Yosef is an organized individual who adds immense value to the work environment, making it a joy for his colleagues.

I wholeheartedly recommend Yosef for any frontend development work and am confident that he will be a valuable asset to any team.

Miguel Bastidas MorenoCRO Developer (Adobe Target + Dynamic Yield) · managed Yosef

Good team member. Proactive and responsible.

Angel RosendoCEO at Filtration Advice Inc. / LPD Technologies

Yosef is a incredible software developer, he has amazing communication skills, he’s always eager to help and resolve any problematic that comes through, driven by his passion to always be better he always delivers and excels at his craft.

Working with him was such a nice experience, i learned a lot from frontend out of him, our clients were always happy with his performance, he develops at a fast pace and at high quality, every project would benefit from having a top profile like his.

As a person he’s always a good talk, charismatic and kind.

Jesus BeltranSoftware Engineer

Yosef demonstrated a high capacity for analysis, performance and responsibility. He was up to all assigned tasks and was always willing to collaborate and solve technical problems presented in Software development. He adapted very quickly to the workflow, managed to maintain stability and delivered quality results during his stay on the project. As a person he is an excellent teammate, he is a good friend, has a good sense of humor and without a doubt, he is someone I would have back on my work team.

Javier Alejandro Valero RiveroSystems Engineer

Great partner with good knowledge of web frontend. He is very disciplined, and responsible, willing to give more than necessary to achieve the goals set.

Mario Jesus Peña PradoSenior Backend Developer

I have had the chance to meet Yosef since many time and he has been both as a good friend as teammate. His skills in problem resolution and his capability to learn is something I admire. He is a person very focused on his work, always willing to complete his tasks responsibly and in the shortest possible time.

Definitely, sharing with Yosef as a co-worker has been a pleasure for me.

Haessler LeónSoftware Engineer

Excelente profesional como pocos me he encontrado en mi vida. Persona integra, capaz y con dos de las virtudes lo cual lo caracteriza como individuo honesto y perseverante. Uno de los mejores en su área y con las capacidades y el coeficiente para ser siempre pieza clave en cualquier proyecto en el cual se le involucre.

Albert ViermaSales Development Representative

Read all recommendations on LinkedIn

About

Calm interfaces for high-stakes flows.

I’m a software engineer with 5+ years of experience across mobile, web and APIs. For the last three I’ve worked on money: transfers, payouts, cards and receipts, where a confusing screen costs someone real money.

I like owning a product end to end, from the first commit to the store release, and I care about the unglamorous parts: error handling, offline states, feature-flagged rollouts and tests.

Based
Rosario, Argentina · Remote (UTC-3)
Languages
Spanish (native) · English (professional working, B2)
Open source
Contributor to SWC (Rust)
Education
Platzi Frontend Developer, plus 65 certifications

Contact

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