Unanswered WhatsApp enquiries
Current friction
Customers enquire outside working hours or the team takes too long to reply.
Software solution
We automate replies, classification and follow-up without removing human attention.
Custom development · Based in Miramar, Buenos Aires
Software that works for you.
I design and build software for businesses and professionals: websites, systems and automations that help attract opportunities, reduce manual work and organize operations.Web, apps, WhatsApp, automation and artificial intelligence.
- Direct access to me
- Custom solutions
- Support after launch
Who's behind SEBA
Sebastián Cardoso Castillo
Software developer
More than 15 years building software for businesses and professionals.
More about meProjects in production
Real projects working today
01 · Operational challenges
Is your business spending hours on tasks that should run automatically?
Every unanswered enquiry can be a lost sale. Every repetitive task takes time away from the business.
Manual scheduling and deposit tracking
Current friction
Finding slots, requesting receipts and confirming payments consumes messages and hours.
Software solution
We connect calendars, payments and reminders so each booking moves forward automatically.
Data scattered across chats and spreadsheets
Current friction
Customer, payment and operational data is spread across disconnected tools.
Software solution
We centralize the information in a clear dashboard that works on any device.
Manual data entry between disconnected tools
Current friction
Copying data between forms, spreadsheets and systems consumes hours and creates errors.
Software solution
We connect your tools so data moves automatically and notifications go out on time.
02 · Solutions
I build the solution your business needs
From a website that converts to a complete operating system: I design and build the right solution for the result you need.
- 01
Acquisition
You have a promotion, course or campaign and need one clear place to send people.Key deliverablesA single page with a single goal: get people to message you, sign up or buy. No menu, no distractions. - 02
Web & digital presence
You need people to find you and understand what you do without relying on Instagram.Key deliverablesYour complete online presence: who you are, what you do and how to contact you, all in a place you own. - 03
Operations
Appointments, payments or customer records no longer fit comfortably in a spreadsheet, or they are scattered across several tools.Key deliverablesA custom system for managing appointments, payments, customers or data around the way your business actually works. - 04
Sales & support
Your team repeats the same task every day, and you already know how much time it consumes.Key deliverablesWorkflows that send notifications, update information and connect the tools you already use.
Start with the problem
Do not know what you need? Start with the problem.
Step 1 / 2
What do you want to improve first?
Looking for transparent investment rates, delivery milestones and ongoing support? View pricing & conditions ↓
03 · Case studies
Real projects working every single day
Behind each project is a real business or professional who had a concrete operational bottleneck. Here is how we solved it from end to end:
Website, operations and member access in one platform
View case studyBeforeDigital presence and daily operations split across chats, notes and spreadsheets.
SolutionA web platform with a public website, admin dashboard and private member portal.
TodayRegistrations, payments and attendance are centralized; members check their status without asking at reception.
A trilingual platform for content and operations
View case studyBeforeInformation and archives were scattered; member and enquiry management was manual.
SolutionA trilingual platform with activities, archives, secure forms and a protected admin panel.
TodayThe community explores and signs up from their phones; the board publishes and manages members in one place.
Appointments, deposits and WhatsApp, automated
View case studyBeforeAppointments and deposits coordinated by hand over WhatsApp, with a risk of double bookings.
SolutionAn application with a schedule, WhatsApp, deposit validation and Google Calendar.
TodayPatients check real availability and book; the daily schedule stays organized automatically.
04 · How I work
A direct, predictable process without surprises
You work directly with me from start to finish. You know exactly what is included, how much it costs and the delivery date before work begins.
Diagnostic
Free initial diagnostic
We understand the problem, review what is slowing the business down and determine whether it makes sense to work together.
Fixed scope and investment proposal
Within 2 business days
You receive a detailed written proposal outlining deliverables, fixed pricing and guaranteed delivery dates with zero hidden fees.
Development with continuous review
Direct developer channel
We validate milestones with functional drafts and prototypes, ensuring every workflow aligns precisely with how your business operates.
Production rollout and handover
Deployment and onboarding
Full production deployment, end-to-end verification and credential handover with clear documentation. Long-term support via SEBA Care.
05 · Pricing & Support
Transparent investment from day one
Fixed quotes with no hidden fees or unexpected costs. Scope, investment details and delivery milestones are agreed in writing before development begins.
Reference values. Final investment depends on the scope defined during the diagnostic. Updated: septiembre de 2026.
Solution
Acquisition
A single page with a single goal: get people to message you, sign up or buy. No menu, no distractions.
Ideal forA gym launching its January promotion and needing it online by Monday
Project investment
View detailsProjects from ARS 160.000
Solution
Web & digital presence
Your complete online presence: who you are, what you do and how to contact you, all in a place you own.
Ideal forGyms and studios that want to show their schedules and plans and attract new members
Project investment
View detailsProjects from ARS 220.000
Solution
Operations
A custom system for managing appointments, payments, customers or data around the way your business actually works.
Ideal forBusinesses managing everything in Excel and starting to overwrite or duplicate information
Project investment
View detailsProjects from ARS 550.000
Solution
Sales & support
Workflows that send notifications, update information and connect the tools you already use.
Ideal forTeams copying information from one place to another every day
Project investment
View detailsBudget based on scope
SEBA Care
Your software keeps working after launch
Monthly planARS 45.000per month
SEBA Care supports the continuity of your live website or system: maintenance, monitoring, support and small improvements without starting a new project every time.
- Infrastructure and domain
- Base infrastructure and the domain are included during the first 12 months of the project. Afterwards, while SEBA Care is active, they remain included in the monthly plan.External services, licences and variable third-party usage costs are billed separately when applicable.
- Maintenance and monitoring
- Technical review, preventive maintenance, updates and basic monitoring to detect problems before they become significant interruptions.
- Backups
- Backups of critical data when the project architecture requires them and the infrastructure in use allows them.
- Support and incidents
- Incidents related to the developed system receive priority attention within SEBA Care.Initial response within one business day.
- Monthly improvement allowance
- 1 hour per month for small adjustments, content updates and minor improvements to existing functionality.Unused time does not roll over.Changes that exceed the allowance or involve new functionality are quoted in advance.
- Project health and metrics
- When the project has measurement in place, you can receive a periodic summary of visits, traffic sources and overall performance.
After the diagnostic, you receive a written proposal with scope, delivery milestones and investment. Timelines begin once the proposal and initial content are approved. Payment milestones and contingencies are agreed before work starts.
06 · Technical engineering
Software engineering and real-world performance
Professional software must be fast, predictable and efficient by design. These metrics were measured directly in your browser upon loading this page: clean, optimized code without bloated templates, ensuring instant response even on unstable mobile connections.
- Visible content
- —s
- LCP · Primary content appears without perceptible delay
- JavaScript downloaded
- —KB
- Minimal transferred payload, preserving data and battery
- Requests required
- —
- Consolidated architecture delivered in a single network roundtrip
- Movement while loading
- —
- CLS 0 · Zero visual shift: elements remain perfectly stable
How it was measured
This page runs 6.3 KB of handwritten inline JavaScript for the animated title, these measurements and the theme selector. Qwik's external modules resume the interactive controls without hydrating the whole page; their actual transfer size is included above.
External JavaScript per page
In June 2026, the mobile median was 711 KB, according to HTTP Archive, which measures millions of pages. Less code does not guarantee a fast website on its own, but it means less data, less work for the phone and fewer opportunities for delay.
Want a second, independent measurement?
Measure with PageSpeed Insights07 · Client perspective
What clients say about working together
Experiences from clients whose projects are already working in their day-to-day operations.
“With Seba, we were able to bring much of the gym's management into one place. Today our website, schedules, content and administration tools are much more organized. What I value most is that he understands what we need and adapts the system to the way we work.”
“We needed to renew our online presence and make it easier to keep the Circle's information up to date. Seba developed a solution adapted to what we needed, and we always had direct communication to adjust every detail of the project.”
“Seba helped me organize and automate much of the appointment and WhatsApp enquiry management. I now save a lot of time that I used to spend replying to messages. I could always speak directly with him and resolve changes as they came up.”
08 · FAQ
Frequently asked questions
The essentials about services, pricing, timelines and the first conversation.
Do you only work with clients from Miramar?
No. I work remotely with businesses and professionals, so a project can be developed regardless of where you are.
Do I need to know which technology I need?
No. The first step is understanding the problem and the goal. From there we define which solution makes sense and which technology is appropriate.
How long does a project take?
It depends on the scope. Before starting, we define what will be developed, the project stages and an estimated timeline.
What happens after launch?
We can continue working through SEBA Care for maintenance, support and continuity, or define new improvements according to the project's needs.
Can you work on an existing system or website?
Yes. I first review the current state of the project and, if working on that base is viable, we define what should be kept, improved or replaced.
How do we get started?
Tell me briefly what you want to solve. We review the case and, if it makes sense to work together, move forward with diagnosis, scope, timeline and investment.
09 · Direct contact
Do you have a problem software could solve?
Tell me how your business works today and what you want to improve. You do not need to have the technical solution defined.
Tell me about your project
Direct access to me · First conversation at no cost