Architecture that scales
Two legacy monoliths (Clojure, PHP) decomposed into 20+ containerized microservices on AWS ECS, with Terraform-first infrastructure and 99.99% uptime in production.
Fractional CTO · Software Architect · Remote
Cayetano Soriano Gallego
I build engineering teams and platforms
that scale without breaking.
CTO and hands-on software architect with 15+ years in tech and 8+ on AWS. I've led two monolith-to-microservices transformations, run engineering organizations as CTO for 7+ years, and now ship LLM agents and RAG pipelines into production.
hello@cayetano.dev · linkedin.com/in/csorianogallego · github.com/neoshadybeat · cayetano.dev · Madrid, Spain
15+
Years in tech
7+
Years as CTO
2
Monolith → microservices migrations
99.99%
Platform uptime
What I bring
Three things I do well
Teams that deliver
Built and scaled engineering organizations as CTO at two companies: OKRs, cross-functional squads, on-call culture, and developer experience as a first-class concern.
AI in production, not slides
Designing agent systems, RAG pipelines and LLM orchestration (Claude, OpenAI, MCP) that ship to real users, with the same reliability bar as any other backend service.
20+
Microservices in production
30%
AWS cost reduction
0
Downtime deployments (Packlink)
50–100+
Developers per meetup organized
Selected work
Problems I've solved
Context → what I did → measurable outcome. The pattern repeats across companies: inherit something fragile, make it boring and reliable, then let the team move fast on top of it.
From a Clojure monolith to 20+ microservices on AWS
- Context
- City-scale eSharing mobility platform blocked by a legacy monolith: slow releases, single points of failure.
- Action
- Designed and led the full re-architecture: 20+ containerized services on ECS, 100% of infrastructure in Terraform, CI/CD with Jenkins, observability with Sentry + PagerDuty.
- Result
- Critical bottlenecks eliminated; platform able to scale to city-wide operations. Promoted to CTO.
Cutting infrastructure cost while raising reliability
- Context
- Growing fleet and traffic; AWS bill scaling faster than revenue; investors requiring technical due diligence.
- Action
- Optimized container orchestration on ECS, introduced event-driven architecture on Kinesis, set OKRs for the tech org, owned security and uptime end to end.
- Result
- ~30% lower AWS spend, 99.99% uptime, and due diligence passed with investors.
Zero-downtime migration to a polyglot architecture
- Context
- High-traffic e-commerce shipping platform (Packlink Pro, eBay integration) on a monolithic PHP codebase.
- Action
- Drove the migration to Java/Scala/Python microservices with RabbitMQ event patterns and Cassandra/Redis storage.
- Result
- Zero-downtime deployments across peak e-commerce operations.
App load time from 10 s to under 1 s
- Context
- Consumer app growing fast with a small team: 10-second loads, scalability pain, slow releases, dependency drift and no clear security baseline.
- Action
- Resource loading optimization, lazy vs eager data loading, DB indexes, Redis caching and rate limiting; CI/CD with AI agents, automated dependency updates and a test harness; security best practices; Terraform for all infrastructure; Sentry, monitoring, analytics and per-call metrics.
- Result
- App load time cut from ~10 s to under 1 s; predictable releases; infrastructure reproducible and fully monitored.
About me
Who I am
I'm a CTO who still reads pull requests. Over 15+ years I've gone from web developer to architect to running technology for two companies, and I've kept one rule: own the whole stack, from the Terraform module to the on-call rotation to the roadmap conversation with the board.
I've taken companies from legacy monoliths to cloud-native microservices on AWS, and I've done the unglamorous work that makes that stick: CI/CD, observability, cost control, security, and technical due diligence with investors.
Today I'm focused on AI systems in production: autonomous agents, RAG pipelines, LLM orchestration and MCP tooling, built with the same discipline as any other backend service. I speak Spanish and English and work equally well in either.
Email
hello@cayetano.dev
LinkedIn
linkedin.com/in/csorianogallego
GitHub
github.com/neoshadybeat
Location
Full remote · based in Madrid, Spain (CET)
Languages
Spanish (native) · English (professional)
Career path
Experience
Independent
Apr 2026 — Present
Fractional CTO & Software Architect
Remote
- Fractional CTO and hands-on architect/developer for early-stage companies: technical strategy, architecture reviews, cloud and delivery setup.
- enolovers.app (client): cut app load time from ~10 s to under 1 s (resource loading, lazy vs eager data, DB indexes, Redis caching, rate limiting); CI/CD with AI agents, automated dependency updates and a test harness; security best practices; infrastructure in Terraform; Sentry, monitoring, analytics and per-call metrics.
- Deep-dive training in security, AI/LLM systems, software architecture and blockchain, applied directly to client work.
ShareTech
Mar 2023 — Apr 2026
Chief Technology Officer
Madrid, Spain
- Owned the technology vision and roadmap; final say on cloud architecture, build-vs-buy and platform investments.
- Led cross-functional engineering squads; set standards for microservices governance, reliability and developer experience.
- Hands-on across infrastructure automation (Terraform, ECS), AWS cost optimization and on-call/observability with Sentry + PagerDuty.
- Vendor and partner contracts (M2M and cybersecurity integrations with Telefónica); technical counterpart for Pamplona City Council.
- Operations & logistics tooling: metrics, SLAs, reporting dashboards and cost optimization.
- End-to-end observability: OpenTelemetry instrumentation, Datadog/New Relic, CloudWatch, Kibana, Sentry and PagerDuty on-call.
- Hands-on backend development; introduced LLM-assisted workflows into the engineering process.
Ride On
2019 — Mar 2023
Chief Technology Officer
Madrid, Spain
- Promoted from Architect to CTO to own the full technology strategy of the eSharing mobility platform (remote since 2020).
- Scaled the engineering organization and introduced OKRs for the tech department.
- Drove event-driven architecture on AWS Kinesis; optimized container orchestration on ECS, cutting infrastructure cost ~30%.
- Directly accountable for uptime (99.99%), security and technical due diligence with investors.
- Vendor and partner contracts (M2M and cybersecurity with Telefónica); technical counterpart for city councils in Miami, Dundee, Leicester and Pamplona.
- Operations & logistics: internal tooling, metrics, SLAs and reporting dashboards.
- End-to-end observability: instrumented every service with OpenTracing / OpenTelemetry (distributed tracing), structured metrics and alerting (New Relic, Datadog, CloudWatch, Kibana, Sentry, PagerDuty) — from request to database.
Ride On
2018 — 2019
Software Architect
Madrid, Spain
- Led the complete platform re-architecture: legacy Clojure monolith → 20+ containerized microservices on AWS ECS.
- Authored the entire Infrastructure-as-Code layer in Terraform; automated CI/CD with Jenkins, images with Ansible + Packer.
- Established observability with Sentry and PagerDuty; removed the bottlenecks blocking city-wide scale.
Kimia
2017
Software Architect
Madrid, Spain
- Designed and delivered high-throughput backend services in Go, backed by Redis and Elasticsearch.
- Built real-time monitoring and alerting pipelines that improved incident response times and reliability.
Packlink
2015 — 2017
Backend Engineer
Madrid, Spain
- Key contributor to the Packlink Pro and eBay shipping integration backend.
- Drove the migration from a PHP monolith to polyglot microservices (Java, Scala, Python) with RabbitMQ, Cassandra and Redis.
- Zero-downtime deployments across high-traffic e-commerce operations.
- Platform monitoring and on-call: Kibana/Elasticsearch dashboards, CloudWatch, Sentry and PagerDuty for a high-availability product.
Betabeers
2012 — 2015
Community Organizer & Speaker
Barcelona & Cádiz, Spain
- Co-founded and led the Betabeers chapters in Cádiz and Barcelona: monthly meetups for 50–100+ developers and founders.
- Built a local tech community connecting startups, engineers and investors.
Softonic
2013 — 2014
Backend Engineer
Barcelona, Spain
- Backend for the Softonic Downloader, serving millions of daily downloads.
- Data pipelines on the Hadoop ecosystem (Hive, Oozie); TDD with PHPUnit.
Crononauta
2012 — 2013
Web Developer
Spain
- Built and maintained content-driven web applications with PHP and Drupal 7, from requirements to production.
Soluciones DTV
2011
Team Lead
Spain
- First leadership role: managed a development team shipping a social networking platform from scratch, from technical design to launch.
Tech stack
Skills & technologies
AI, agents & LLMs
Agents, RAG and LLM orchestration shipped to real users; MCP tooling and AI-assisted engineering workflows.
Cloud & infrastructure
8+ years designing and running AWS platforms: containers on ECS, Terraform-first infrastructure, event streaming.
Backend
15+ years across PHP, Java/Spring Boot, Python, Scala and Go; from monoliths to polyglot microservices.
Data & storage
Choosing and operating the right store per workload: key-value, search, cache, wide-column and relational.
DevOps, CI/CD & observability
CI/CD pipelines, immutable images, on-call and observability; reliability as an engineering practice, not a team.
Leadership
7+ years as CTO: roadmap, hiring, OKRs, vendor contracts, due diligence, budgets and city-council stakeholders.
Credentials
Education & certifications
Universidad de Cádiz
Computer Systems Engineering
2007 — 2014
Megathon W8 Cádiz
Hackathon award
Zend Certified PHP Engineer
Zend
MongoDB Certified DBA
MongoDB Inc.
MongoDB Certified Developer
MongoDB Inc.
MySQL 5.6 Developer
Oracle
Next step
What I'm looking for
To save us both time: this is where I add the most value, and the kind of company where I've done it before.
Roles
- CTO / VP of Engineering
- Head of Platform / Infrastructure
- Principal / Staff Engineer (hands-on architecture)
- Fractional CTO or technical advisor
Company
- Scale-ups moving from "it works" to "it scales"
- Product companies with real traffic and real infra bills
- Teams shipping AI/LLM features to production
- Mobility, logistics, marketplaces, SaaS
Setup
- Full remote (CET ±3h); occasional travel is fine
- Spanish or English working language
- Full-time or fractional engagements
- Available on short notice