Yosef Blandin · Rosario, ArgentinaMobile and frontend engineer, focused on payments and banking.
5+ years shipping React, React Native, Next.js and TypeScript, the last three in payments and banking: a bank’s iOS and Android app, and a 14-language aid-payments app NGOs use in the field.
Open to new roles and freelance work

- 5+years shipping web and mobile products
- 500active users on a bank’s iOS and Android app
- 14languages, including right-to-left Arabic
- 8s→1.5sinitial load on a client site, bounce rate down 13%
Selected work
Products in production
Six products, from aid payments in the field to a bank’s app in the stores. Each one lists the problem, what I built and what changed.
14 languagesincluding right-to-left Arabic, with offline login
- Release
- 1.0 → 2.1 in 9 months
- Users
- 100 active vendors
- Status
- In production
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.

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.

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.

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.

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.

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%.
Experience
5+ years, all remote
Product teams, an agency and a startup, working across time zones from UTC-3.
- Oct 2025 – PresentCurrent
Frontend and Mobile Engineer · AIDONIC
Vendor app 1.0 → 2.1 in 14 languages; payouts, access control and the monorepo move.
- Oct 2023 – PresentMaintenance
Mobile Engineer · Partnet Group
Led the Bangente banking app from code to both stores; maintaining it since Nov 2025.
- Aug 2024 – Oct 2025
Frontend Engineer · Smart Compliance
Real-time compliance dashboards over WebSockets, with a 10k–20k point heat-map.
- Feb 2022 – Sep 2023
Frontend Engineer · Turpial Development
Initial load 8s → 1.5s, pharma search +8% traffic, student dashboards.
- Feb 2021 – Jan 2022
Frontend Engineer · Wingoo.io
Sole frontend developer; Rails to Next.js and TypeScript, CSS bloat down 80%.
Skills
Tools I use every week
Grouped by the job they do, not by how long I’ve known them.
Languages
Web and mobile
Real-time and data
State and UI
Testing and delivery
AI tools and open source
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 YosefGood team member. Proactive and responsible.
Angel RosendoCEO at Filtration Advice Inc. / LPD TechnologiesYosef 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 EngineerYosef 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 EngineerGreat 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 DeveloperI 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 EngineerExcelente 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 RepresentativeAbout
Calm interfaces for high-stakes flows.
I’m a frontend and mobile engineer with 5+ years of experience. 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
Building something with money in it?
I usually reply within one working day.