Therry Miranda
Openbank US
$11BBuilt Openbank US web payments and transfers from zero — the money-movement surface of a digital bank that has gathered $11B in deposits from 100,000+ customers.
Staff Engineer · Remote Contractor
Available for engagementsStaff-level engineering, contractor velocity.
Built Openbank’s US web payments from zero — $11B in deposits, Santander’s digital bank. Now contracting remotely from Spain, on EU hours, B2B invoice.
Shipped systems in production
CrewFactory
10A self-hosted platform to build, orchestrate and benchmark multi-agent systems entirely from the browser — with algorithmic negotiation, live streaming and an efficiency laboratory.
LOEWE
0.9sRebuilt the storefront rendering pipeline of a global luxury brand, cutting the largest contentful paint from 3.0s to under 1s while opening the layout for a WCAG AA audit.
Banky
2,500+Self-host your own banking dashboard with read-only access and zero server costs, on Cloudflare Edge or local Node.
De idea a producto
20A book and a persuasion landing page with 20 concrete hacks that take a developer from an unlaunched idea to their first paying customer.
u2-agent
~250A zero-dependency CLI that lets AI agents control Android devices with ~250 tokens per screen and sub-15ms actions, instead of the 15,000 tokens and ~800ms of a raw UIAutomator dump.
Aira
AndroidPersonalised wellness routines that adapt to your real life, built by an AI that understands your needs.
SignalHub
PushA marketplace for personalised alerts and push notifications that turns subscribers into active users.
10xDev
10xA platform that speeds up development with professional tools, templates and UI blocks, so a new SaaS can be assembled instead of built from scratch.
Chordify
6Transform your inspiration into sound. Chordify is an interactive audio synthesizer built on browser-native APIs that lets musicians explore instruments, build chord progressions and save their ideas.
Vibe Better
LiveA platform that analyses and rewrites your coding prompts, turning vague instructions into precise, high-leverage ones.
Verified output
Production figures from shipped systems| Ref | Line | Figure | Context |
|---|---|---|---|
| 01 | Web payments & transfers built from zero | Openbank US | Santander Group digital bank — payments & transfers vertical, 2025–present |
| 02 | US deposits since launch (late 2024) | $11B | Openbank US public figure as of Jul 2026 |
| 03 | US customers | 100,000+ | Openbank US public figure, 2026 |
| 04 | Page load before → after | 3.0s → 0.9s | LOEWE project at Capgemini (Jan 2023 – Mar 2025) · metric: LCP |
| 05 | Accessibility raised to WCAG AA | LOEWE | Capgemini project, same engagement as row 04 · observable on the live store |
| 06 | Engineers I have led in a squad | 5 people | Capgemini (Jan 2023 – Mar 2025) — squad lead responsibility |
| 07 | Copies sold of my book | 500 | "From Idea to Product Like the 1%" — sold via Gumroad |
| 08 | Shipping production code since | 2018 | Continuous professional track record |
Consignments
11 systems in the showcaseCSN-01openbank.usProduction
Openbank US
I built the web payments and transfer flows for Openbank's US launch, a Santander Group digital bank. Every mutation is idempotent and traceable before it is confirmed, and the UI state never leads the backend. The result is a bank product that shipped fast without ever shipping wrong.
- US deposits since launch
- $11B
- customers
- 100,000+
- Idempotent transfers. Every money-movement mutation is safe to retry without duplication.
- Audit-first data model. Mutations are traceable before they are confirmed.
- Backend-led UI state. The interface never anticipates what the server has not confirmed.
- Accessible banking. Keyboard and screen-reader support for high-stakes financial flows.
React · TypeScript · REST APIs · Accessibility · Testing
Open live system · $11BCSN-02crewfy.siteLive
CrewFactory
CrewFactory is a self-hosted multi-agent platform powered by Qwen Cloud. You create agents with roles and system prompts, connect them into group channels with configurable routing and negotiation protocols, and measure their collaboration efficiency against single-agent baselines. It was built for the Qwen Cloud Hackathon 2026 (Track 3 — Agent Society).
- MCP catalog servers
- 10
- Qwen 3.x models
- 8
- LLM providers
- 35+
- Multi-agent channels. Hierarchical roles (lead, senior, member, observer) with @mention routing and reply modes.
- Algorithmic negotiation. Regex-driven agreement/counter/rejection state machine with automatic arbiter escalation.
- Efficiency laboratory. A/B/C comparison: single-agent baseline vs horizontal vs hierarchical, with LLM-Judge scoring.
- MCP integration. Ten catalog servers over stdio and HTTP/SSE, loaded as native agent tools.
Bun · Hono · TypeScript · React 19 · Tailwind CSS v4 · Vite · WebSocket · SQLite · Docker · Qwen / DashScope
Open live system · 10CSN-03loewe.comProduction
LOEWE
On the LOEWE eCommerce platform I owned frontend performance and accessibility. The work removed render-blocking resources, moved the experience to a static-first model, optimised the image pipeline end to end, and brought the interface to WCAG AA — all inside a luxury brand whose slowness directly contradicted the product.
- LCP (from 3.0s)
- 0.9s
- WCAG conformance
- AA
- Core Web Vitals green
- 100%
- Static-first rendering. Removed render-blocking resources so the first paint is server-ready.
- Image pipeline. End-to-end optimisation of formats, sizes and delivery for a media-heavy storefront.
- WCAG AA audit. Contrast, semantics and keyboard navigation fixed while the layout was already open.
- Web Vitals budget. Measured LCP, CLS and INP against a permanent performance budget.
React · TypeScript · Styled Components · Jest · Web Vitals · WCAG AA
Open live system · 0.9sCSN-04trybanky.therry.devLive
Banky
Banky connects bank accounts (Santander, Revolut and 2,500+ EU/UK banks) through Enable Banking AISP read-only. It gives instant balances, rule-based categorisation, custom cutoff billing cycles, budgets and analytics — fully self-hostable on Cloudflare Workers + D1 or Docker, with zero-trust security throughout.
- EU/UK banks
- 2,500+
- AISP access
- Read-only
- Cloudflare self-hosted
- Serverless
- Multi-bank aggregation. Link many banks in one place with no transfer permissions.
- Sub-millisecond queries. Data synced into local SQLite or Cloudflare D1 with local caching.
- Smart categorisation. Rule-based tagging, regex matching and remembered manual labels.
- Custom billing cycles. Configurable statement cutoff days per account or globally.
React 19 · Vite · Tailwind CSS v4 · Hono · TypeScript · Zod · Drizzle ORM · SQLite / Cloudflare D1 · Cloudflare Workers/Pages · Docker · Enable Banking
Open live system · 2,500+CSN-05deideaaproducto.therry.devLive
De idea a producto
“De idea a producto” closes the gap between “I have an idea” and “I got paid”. Written by a developer for developers, it offers 20 actionable hacks — “The Mother Test”, “Build in Public”, “The Art of the Ask” — distilled from real launches. It includes the book in PDF/EPUB/MOBI, a launch checklist and access to a private community.
- actionable hacks
- 20
- book formats
- 3
- no-questions guarantee
- 30 days
- 20 actionable hacks. Every chapter pushes you to do something today, not to know more.
- The enemy is doubt. It attacks the fear and perfectionism that stop you from launching.
- Multi-formato. Book in PDF, EPUB and MOBI, plus a Notion checklist and prompts.
- A single-decision landing page. The whole page exists for one action: buy.
Vite · React · TypeScript · Tailwind CSS · shadcn/ui · Gumroad
Open live system · 20CSN-06u2agent.therry.devLive
u2-agent
u2-agent is an LLM-native Android automation tool built on Bun and TypeScript. It talks to a native uiautomator2 JSON-RPC daemon over ADB and deduplicates the view hierarchy into a compact semantic tree where every actionable element gets an ephemeral handle (@1, @2, …). Built for the OpenCode Go ecosystem and shipped with CI, docs and a compiled single-file binary.
- tokens per screen (vs ~15,000)
- ~250
- cached action latency
- <15ms
- fewer tokens
- 85%
- Semantic tree. Deduplicated view hierarchy with ephemeral handles (@1, @2, …).
- Sub-15ms actions. In-memory daemon and cached actions instead of XML serialization.
- Zero dependencies. Built on Bun and TypeScript native APIs, shipped as one binary.
- 3-step agent loop. A minimal perceive → decide → act cycle designed for LLMs.
Bun · TypeScript · ADB · uiautomator2 · Cloudflare Pages
Open live system · ~250Engagement waybill
Clear terms, no hidden line items- Engagement
- Contractor. One B2B invoice per month.
- Setup
- No EOR. No entity. No payroll in Spain.
- Based in
- Spain (CET / CEST)
- Core hours
- 09:00–18:00 CET, Mon–Fri
- Overlap
- Full EU day · ~3 h with US East CoastExact overlap for your timezone appears in the receipt below.
- Scope
- One client engagement at a time.
References
Loaded and discharged“Your attitude is really great!! You are always willing to take on new tasks and collaborate with the team. Your deliveries are strong, even surfacing issues that had not been considered, which reinforces the sense of team and ownership of the product.”
Michelle Fainberg WhitelowProduct Manager · JP Morgan Chase
“Teamwork: The adaptation to the USA team has been great, both on a personal level (fitting in very well with teammates) and on a technical level (in the quality and efficiency of the features implemented). Focus on delivery quality, both from a technical standpoint (ensuring the defined best practices are maintained, code scalability, and following the guidelines of the Platforms and Architecture teams) and from a product standpoint (ensuring the developments match what is described in the User Stories and are delivered with the highest quality, correctly meeting the acceptance criteria with the fewest possible bugs). Knowledge sharing: He has always been attentive to helping the rest of his colleagues, even from other USA teams, whether through onboarding or technical explanations, as well as helping set up work computers and reviewing any technical questions.”
Ronaldo Medina HuertaEngineering Associate Director · Openbank
“Therry is a true professional. He's always ready to take action and is a very kind person. Thanks to his proactivity and eagerness to contribute, there's great potential in his work. He's willing to help and listen at any time. I'm very happy to have him as part of the team. Thanks, Therry!”
Jesús María ArandaEngineering Associate Manager · Openbank
“He meets every task within the established deadline and always maintains quality standards. Broad technical knowledge of the entire project and of future improvements. He is open to constructive criticism. He is always willing to share his knowledge and experience. Willing to collaborate and solve problems as a team. He genuinely makes work more enjoyable. Constant help and support for every member of the team.”
Rosangelis García DortaSr Software Engineer · Openbank
“As a team we manage to meet different objectives, we finished a stable version for the production release of the program which was a success. We continued to maintain the application by delivering our tasks in the proposed times. In addition, we worked in a pleasant, healthy work environment with efficient communication. Therry is a great developer, he handles every concept related to his work very well and is incredibly proactive.”
Diego Alejandro GómezSr Software Engineer · Openbank
I’m the lead who makes the team faster, not the one who does everything.
- Squads
Led squads of 5 engineers at Capgemini (2023–2025) — delivery, code quality and team velocity.
- Teaching
Mentored developers 1:1 and built learning tools for engineers through 10xDev.
- Writing
Wrote the playbook “From Idea to Product Like the 1%” — self-published and sold via Gumroad.
Empathy Before Abstraction
Before designing a system or choosing an architectural pattern, understand the engineers who will maintain it and the people whose workflows rely on it.
Craft Over Hype
Choose battle-tested fundamentals over passing trends. Elegance lies in simplicity, tight feedback loops, and deterministic behavior under stress.
Calm Under Pressure
Complex production incidents and tight deadlines demand clarity, composure, and methodical diagnostics rather than frantic action.
Available for engagements · Spain (CET)
B2B invoice · No EOR required