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I build the whole product — app, backend and infrastructure — and hand you something that runs in production, not a prototype somebody has to redo.

Agustín Davérède

Software Engineer& Fractional CTO

ex-Paxos · ex-Lemon Cash · ex-CTO at BAG

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15 minutes, free — you leave with an opinion

Previously

  • Paxos
  • Lemon Cash
  • Catapult Health
  • BAG

Anyone can put together an AI demo in an afternoon. A product that serves real users every day is a different job.

Nine years building products end to end — web, mobile and backend — in fintech, crypto and health. AI systems of mine run in production at three companies. I have led teams of up to twelve people.

  • 9years building products end to end, in production
  • 3,000+interviews run without an engineer in the room
  • 10kfirst users at Lemon Cash, as founding engineer
  • 12engineers led as CTO — I can run your team, or build it
As CEO, what I single out is how well he grasped what the business needed, and acted on it. He was enormously valuable to the company.
Martín González RaskovskyCEO, BAG

Where I come in

Four ways this usually starts.

  • 01

    Products built end to end

    I design, build and ship the whole thing: the app, the backend, the infrastructure and the deploy pipeline. On my own, or working alongside your team. If it moves money I have been at the protocol level, not just the interface — a coin-selection engine of my own, keys handled on the device, and the core product of a US-regulated exchange.

    You call me whenYou have a validated idea and you need it to exist. Or you have a rushed MVP that no longer holds up.

  • 02

    AI that survives production

    The work is everything the demo skips: keeping the cost per user sane, stopping it from making things up, and keeping it standing when the model provider has a bad day. In the product, and also beside it — automating a process a person does by hand today, assistants wired into your own data. Mine have been running that way for three companies.

    You call me whenYou already added AI and it doesn’t quite work. Or your team burns hours on work a machine should be doing.

  • 03

    Fractional CTO

    Technical direction part-time, without adding a full-time executive: the architecture calls, what to build and in what order, hiring and standards. And the business read on each of those — at this level every technical decision is a decision about money and time.

    You call me whenYou have a team but nobody making the big calls. Or you’re starting and don’t want to get the first five decisions wrong — the expensive ones to reverse.

  • 04

    Technical audit and second opinion

    The smallest way to work together. I review the code, the architecture and how the team works, and hand you a diagnosis with priorities: what is urgent, what matters, and what can wait. Written, not a chat.

    You call me whenYou’re investing in a company and want to know what you’re buying. You inherited a product and don’t know its state. Your team says everything needs a rewrite and you want an independent read.

How we work

  • Short diagnosisOne or two weeks, closed scope, written report with priorities. Enough to decide on, and it commits you to nothing.
  • Fixed projectScope, deadline and price agreed before starting. For when it is already clear what needs building.
  • Monthly retainerContinuous availability for development, architecture calls or technical direction. For work that is ongoing and has no obvious end.

Remote from Buenos Aires — one to two hours from New York, and a full overlap with the European afternoon. English or Spanish. The first call is 15 minutes and free.

Where you can see the work

Six products, from the core of a regulated US exchange to an AI platform running in production today.

01 Paxos

The core product of a regulated US exchange

Full Stack Engineer

A regulated crypto and stablecoin company in New York. I worked on the app customers use to hold, trade and move their money — where a rounding error is not a bug report, it is somebody’s balance.

  • Wrote @paxosglobal/number, the library the product uses to handle amounts of money exactly, with no floating-point surprises.
  • Built the shared building blocks and standards the rest of the engineers worked from.

Cut the app’s initial load time by 20%.

  • React
  • TypeScript
  • Node.js
  • PostgreSQL

02 Lemon Cash

From zero to the first 10,000 users

Founding Engineer

I was the first engineer, building alongside the CTO. There was no app yet — I built the iOS and Android product, and kept building it while the company grew into a crypto-fintech moving real money.

  • Built the core product from an empty repository: the app people used every day.
  • Set up the release machinery so shipping an update stopped being a risky event.

Grew with the product to its first 10,000 users.

  • React Native
  • Ionic
  • Node.js
  • MySQL
  • AWS
  • Appium

03 NTRVSTA

Technical interviews without pulling engineers off their work

System architect — owned the architecture, led the team

Every technical interview costs an hour of one of your most expensive people, and most of those hours end in a no. NTRVSTA runs that round on its own: an AI avatar holds the conversation, watches the candidate write code, and scores it.

  • Live coding inside the interview, with difficulty, hints and follow-ups adapting to each answer.
  • Runs in 8 languages, around the clock, and plugs into the hiring tools you already pay for.

3,000+ candidates interviewed across 3 companies, running in production today.

  • React
  • TypeScript
  • AWS Amplify Gen 2
  • DynamoDB
  • Step Functions
  • Claude / OpenAI
  • HeyGen
  • ElevenLabs
ntrvsta.com
NTRVSTA — Technical interviews without pulling engineers off their work

04 baset.io

A Bitcoin app where the user holds their own money

Sole engineer — app, backend and infrastructure

A wallet on iOS, Android and web where nobody but the owner can touch the funds — the keys never leave their phone. Built end to end by one person, in private beta.

  • Payments settle in seconds for cents, across Bitcoin, Liquid and Lightning.
  • I wrote the fee and coin-selection engine myself, because getting it approximately right is how people lose money.

Three platforms, one engineer, in private beta.

  • React Native
  • TypeScript
  • Node / Express
  • MySQL
  • bitcoinjs-lib
  • liquidjs-lib
  • Breez SDK
  • AWS
baset.io
baset.io — A Bitcoin app where the user holds their own money

  • Catapult Health

    A US preventive-care platform of 28 services: built one, and the shared pieces the rest run on.

  • BAG

    As CTO, set up the engineering from scratch and led the teams. Cut base development costs by 30%.

    artbag.io

What you’re probably wondering

  • Can one person really do this?

    For baset.io, yes — three platforms, one engineer. When it needs more than that I bring the team with me — engineers I have already worked with — and I run them. I set up BAG’s engineering from scratch and led twelve people.

  • When could you start?

    A short diagnosis usually fits within a couple of weeks. A build depends on what is already running — ask and I will tell you straight.

  • What if the scope changes?

    On a fixed project, scope, deadline and price are agreed before anything starts, so a change is a conversation rather than an invoice you did not expect.

  • How do we work across time zones?

    From Buenos Aires: one to two hours from New York, and your whole afternoon if you are in Europe. English or Spanish.

His solutions weren’t just technically sound — they were built to move our commercial goals. And his grasp of the legal and regulatory implications of what we were doing let us navigate more than one situation safely.
Ignacio ElffmanHead of Product, artbag