Custom software built to production standards: maintainable code, real integrations with your systems and frictionless deployments. From requirements to deploy, a single Software Engineer owning the whole stack.
One specialist instead of a team. From architecture to deployment — built to scale, secure and reliable.
Want details on any service? Ask Focusyn — stack, timelines and how to get started.
AI assistants connected to your real systems — not template chatbots. Running 24/7 on WhatsApp, Instagram and your site with full conversation context and human handoff when needed.
Resolve 70% of repetitive inquiries automatically. Reads your docs, FAQs and policies, answers in seconds and escalates when it detects frustration or complexity.
Engages every visitor, qualifies against your criteria and books directly into your calendar. Your team only talks to qualified leads.
Private bots your team queries like a colleague — policies, processes, customer data, order status. Connected to your APIs and databases with role-based access.
Product recommendations, stock and shipping answers, smart upsells and post-sale resolution. Plugged into your catalog, CRM and real-time tracking.
Live demo
You're already talking to one: Focusyn.
The assistant on this page runs the same stack we'd deploy for yours. Try it, push it, then let's talk.
Production work across fintech, retail, internal tooling and AI — shipped, scaled and maintained.
iOS engineering for a LATAM fintech serving thousands of users. Payment flows, KYC and push notifications, backed by automated testing (XCTest, UITest), production observability (Embrace, Datadog), product analytics (Amplitude, Firebase) and automated release pipelines on Bitrise.
End-to-end Flutter app for a retail chain — store directory, promotions and loyalty program with Stripe payments. State managed with Riverpod, Node.js backend on Supabase with PostgreSQL, push and analytics through Firebase, error monitoring via Sentry, and continuous releases on Codemagic.
WhatsApp AI assistant for SMBs — 24/7 customer resolution against a custom knowledge base. RAG with Pinecone embeddings, orchestration via n8n and Redis, native integration with WhatsApp Cloud API and Meta Graph, Claude and OpenAI models per use case, all monitored with Sentry.
This very site. Next.js 16 + TypeScript + Tailwind v4 with bilingual SSR via next-intl, AI assistant powered by Gemini with observability in self-hosted Langfuse, analytics through Umami, rate-limiting on Upstash Redis and transactional emails via Resend. Deployed on self-hosted Docker.
Curious about a project? Ask Focusyn — stack, challenges and similar work.
Repeatable, transparent, designed to remove uncertainty. You always know where we are, what's next and what's expected.
Free intro conversation on WhatsApp (text or audio notes) to understand goals, constraints and timeline. You receive a written technical scope and a fixed proposal — no surprises.
Technical architecture, stack selection, milestones and deliverables. Clear roadmap with weekly checkpoints.
Short development cycles. Working build every week — screen recordings or live demo — so you give feedback before anything solidifies.
QA, performance audits and store/deploy prep. App Store and Play Store submissions handled end-to-end.
Bug fixes, iterations and monitoring included for the first weeks. Monthly retainer available for ongoing work.
Want to understand the full process? Ask Focusyn — stages, deliverables, timelines and what to expect.
I'm Agustín Errecalde — Software Engineer with 7+ years designing, building and shipping software across multiple industries.
7+ years shipping product end-to-end at global fintechs, retail and SaaS — owning every feature with focus on scalability, security and reliability.
Full-stack: Apple ecosystem (Swift/SwiftUI), cross-platform (Flutter), modern web (Next.js, TypeScript) and backend (Node.js, Supabase, PostgreSQL).
AI integration: Claude and GPT-powered assistants with custom knowledge bases, RAG pipelines and native integration into business workflows.
Based in Argentina, remote worldwide. Async-first, clear communication and code built to scale safely and reliably.
Want to know more about my career? Ask Focusyn — roles, companies or download the full CV.
Product idea, technical challenge, or a project that needs to scale safely and reliably? Get in touch — I respond within 2 hours.