Europe · $40K–$200K
Full Stack AI Developer in Spain
Direct answer
To hire full stack ai developer spain, hire a senior engineer with production launches, clear English communication, and guaranteed working-hours overlap. Senior engineers in Barcelona and Madrid typically earn €40K–60K. Typical remote full stack ai developer projects run $40K–$200K. Dhairya Senjaliya works with teams across Barcelona and Madrid and the rest of Spain — Top Rated on Upwork, Expensify contributor, 20+ app launches.
Looking to hire full stack ai developer for a team in Spain? Spain is home to a fast-rising startup scene led by Barcelona, plus a large product and agency market — and I help founders, CTOs, and agencies there ship production full-stack work: React Native and Next.js frontends, Python/FastAPI backends, RAG systems, and AI agents, with weekly demos and async updates aligned to CET — startups and agencies.
Hiring a full stack ai developer for Spain
Hiring a full stack ai developer in Spain usually means competing with Barcelona and Madrid pay. Senior engineers in Barcelona and Madrid typically earn €40K–60K. Spanish agencies commonly quote €50–100/hr. Working with a senior remote engineer typically saves 40–60% versus local ES agency rates while keeping production quality, billed transparently in EUR or USD — with one accountable owner across mobile, web, backend, and AI, and no multi-vendor coordination or junior hand-offs.
What a full stack ai developer costs in Spain
| Option | Typical cost | What to factor in |
|---|---|---|
| Hire in-house in Spain | Senior engineers in Barcelona and Madrid typically earn €40K–60K. | Add a 3–6 month hiring cycle, plus benefits and payroll overhead. |
| Local ES agency | Spanish agencies commonly quote €50–100/hr. | Multi-person teams, project minimums, and junior hand-offs are common. |
| Senior remote engineer (me) | $40K–$200K per project, milestone-based | One accountable senior owner. Live overlap across your full business day — roughly 9 AM to 6 PM CET. |
Salary and agency ranges are typical published figures from Glassdoor, Arc.dev, Stack Overflow survey data, and public agency rate cards (2026) — see sources below. Every project is quoted on scope, not headcount.
Real-world engagements this covers
A typical Spain brief
A Barcelona marketplace adding Bizum payments and Spanish plus Catalan localisation.
AI SaaS end to end
Next.js frontend, FastAPI backend, RAG or agent core, Stripe billing — the full AI product stack from one senior owner, with evals so quality is measured.
Mobile AI product
React Native app with streaming AI features and the Python backend that powers them — the exact stack of my open-source RAG starter plus its mobile part 2.
Add AI to an existing product safely
Your users want AI features; your codebase wasn't built for them. I integrate LLM features with guardrails, cost controls, and rollback paths.
What to look for in a full stack ai developer
- →Working products across the whole stack — frontend, API, and AI layer
- →Eval-driven AI development, not vibes-driven prompting
- →Cost architecture: caching, routing, and budgets before launch
- →Open-source or live work you can verify in five minutes
Why hire remotely for Spain
ES timezone fit
Live overlap across your full business day — roughly 9 AM to 6 PM CET.
Built for Spain's market
Spain is home to a fast-rising startup scene led by Barcelona, plus a large product and agency market. I build the mobile, web, and AI products these teams ship — from MVP to production scale.
Proven delivery
Guest Engineer at Expensify, Top Rated on Upwork ($100K+ earned), 20+ App Store launches, and 7+ years of production work.
What you get
- ✓Full Stack AI Developer engagement scoped for Spain stakeholders (CET — startups and agencies)
- ✓Production TypeScript / Python codebase with documentation
- ✓Weekly demos and milestone-based delivery, billed in EUR or USD
- ✓Security-conscious APIs (auth, rate limits, observability)
- ✓GDPR-aware data handling patterns where applicable
How an engagement starts
- 1.Send a short brief — goals, platforms, timeline — to dhairyasenjaliya@gmail.com or through the contact form.
- 2.Free 30-minute scoping call in your working hours. You leave with an honest read on scope and cost, whether or not we work together.
- 3.A written proposal with fixed-scope milestones — you approve each milestone before it's built, and you can stop at any boundary.
- 4.Weekly demos of working software, async updates between them, and delivery aligned to CET — startups and agencies.
Proof, not promises
FAQ
How much does it cost to hire full stack ai developer in Spain?
Senior engineers in Barcelona and Madrid typically earn €40K–60K. Spanish agencies commonly quote €50–100/hr. Typical remote full stack ai developer projects with me run $40K–$200K depending on scope, billed in EUR or USD on fixed-scope milestones — you approve each milestone before it's built.
Do you work with clients in Spain?
Yes. I work remotely with Spain founders, product teams, and agencies — from Barcelona and Madrid to fully distributed teams. English-first communication, contracts via Upwork or a direct SOW.
How does the timezone difference work with Spain?
Live overlap across your full business day — roughly 9 AM to 6 PM CET. Weekly demos are scheduled in your hours, and async updates keep the thread moving between them.
How do contracts and invoicing work for ES companies?
Cross-border B2B invoicing with reverse-charge VAT — no Spanish payroll or EOR required. Payment terms are milestone-based — no large upfront commitments.
Who owns the code and IP?
You do — completely. Work happens in your repositories where possible, IP assignment is written into the SOW, and there is no lock-in: everything is documented so any developer can take over.
Can you ship mobile, web, and AI together?
Yes. React Native + Next.js + Python (FastAPI) + RAG/AI agents under one senior owner — ideal when your Spain team needs to ship mobile, web, and AI without coordinating multiple vendors.
What happens after launch?
Most clients keep a monthly care retainer: dependency updates, store submissions, monitoring, and a priority line for fixes and small features. You can also hand off entirely — the documentation is written for that.
How do we get started?
Book a free 30-minute scoping call on this site, hire through Upwork, or email dhairyasenjaliya@gmail.com with your brief and ES timeline.
More hires in Spain
Sources & further reading
Book a call — full stack ai developer in Spain
30-minute scoping call · Clear milestones · Senior engineer ownership