S.01 / SOFTWARE

Custom software development for businesses that have outgrown standard tools.

Custom software is a system designed for your company’s specific processes, rather than a generic tool you have to adapt to. I design and build platforms, internal web applications, CRMs and integrations around how your team actually works, with the code and data in your name.

Tell me the problem View case studies

02 / THESIS

Build only where it makes a difference.

Standard software is usually the right answer for standard processes.

Custom systems make sense when the way a company works is part of what makes it different.

That is where standard tools start to cost more than they save: parallel spreadsheets, data entered twice, and workflows bent around a vendor’s model instead of the team’s.

03 / SIGNALS

Signs your business has outgrown its tools.

When these signs appear, the problem is no longer the tool. It is that the way you work no longer fits inside it.

01Parallel spreadsheets hold the real process together.
02The same data is entered two or three times in different tools.
03You pay for features you do not use and still miss the ones you need.
04Every tool has its own version of the truth.
05The process is decided by the vendor, not by your team.

A platform built along an irregular process, with modules connected to its curves — FIG. 02Software that follows the shape of the process

04 / WHAT I BUILD

What custom software I build.

Different pieces, one principle: the system is designed around your process and works alongside what already works.

01
Digital platforms
Complete web products with content, users, data and their own administration, designed to keep growing for years.
EvidenceRocio.com · Zentia
02
Internal web applications and back offices
The tools your team uses every day: operations, admin panels, approval workflows and internal management.
EvidenceRocio.com
Custom web application
03
CRMs and sales tools
Pipelines, customer records, tasks, campaigns and follow-up designed around your real sales process, not a vendor’s.
EvidenceZentia
Custom CRM for businesses
04
Customer and partner portals
Private spaces where third parties check, submit or manage information without going through email or spreadsheets.
EvidenceZentia
05
Integrations and APIs
Connecting the tools you already use (ERP, CRM, databases, external services) so data is entered only once.
EvidenceAtalayaIQ
06
Legacy system modernization
Replacing a platform you have outgrown without losing its content, its data or what already works.
EvidenceRocio.com
Legacy system modernization

05 / EVIDENCE

Software built around a real process.

Systems that exist and are documented. No invented figures.

Multi-tenant platform

Zentia

One core for several real-estate agencies, each with its own brand, listings, leads and panel, instead of one product per client.

The agency is identified by its domain or subdomain before anything is rendered.
Row Level Security isolates each agency’s data in the database itself.
Brand, colours and copy live in configuration: a new agency needs no new deployment.
Leads arrive with the properties they viewed and their inferred preferences.

STACK Nuxt 4 / Supabase / PostgreSQL

Case study: Zentia

Editorial platform

Rocio.com

A platform with around 15 years on WordPress rebuilt as its own system, without losing its content or its links.

Replaces the WordPress site the portal had been carrying for around 15 years.
The historical archive migrated to a normalized database.
A custom editorial panel to manage dynamic content.
News, events, brotherhoods and archive connected in one system.

STACK Nuxt 4 / Vue 3 / MariaDB

Case study: Rocio.com

ALSO BUILTGustela CRM, an internal sales-prospecting CRM with pipeline, campaigns, a send queue and automatic exclusion rules, designed around one company’s real sales process. No AI, because it did not need it.

06 / WHEN NOT TO

When not to build custom software.

If an existing tool solves the problem well, using it is usually the best decision. Custom work belongs in the part of the business that standard tools handle worst.

When custom software makes sense

The way you work is part of what makes your business different.
Your team keeps parallel spreadsheets to cover what the tool cannot do.
The same data is entered two or three times in different tools.
You need rules, integrations or permissions no standard product offers.

When it does not

Your process is standard and an existing tool already handles it well.
The problem is configuration or training, not the tool itself.
You need it next week and a proven product can do the job.
Nobody will own the system after launch.

07 / PROCESS

Custom software development: process and timelines.

Six phases and one rule: a first useful piece in production as soon as possible, then grow from there.

FIG. 07Understand → design → build → migrate → launch → evolve

01 — UNDERSTAND
Understand
The problem, the data that exists, the constraints and the goal.
- PROBLEM
- DATA
02 — DESIGN
Design
Data model, architecture and what gets built first. What’s standard stays standard.
- ARCHITECTURE
03 — BUILD
Build
In short deliveries your team can use and correct, not one big launch at the end.
- ITERATIONS
04 — MIGRATE
Migrate
Existing data is cleaned, validated and reconciled with its source.
- DATA
05 — LAUNCH
Launch
In production, with permissions, backups and error logging.
- PRODUCTION
06 — EVOLVE
Evolve
The system changes with the business: improvements, new pieces and maintenance.
- SUPPORT

08 / PRICE

What drives the cost of custom software.

I don’t give fixed prices without seeing the problem. These are the five factors that decide it.

SCOPE
How many processes, screens and user types the first version covers. Starting with the piece that pays back most keeps it down.
INTEGRATIONS
How many systems it has to talk to (ERP, CRM, payment gateways, external services) and whether they offer an API or only exports.
DATA
How much data has to be migrated and what state it’s in. Messy data costs more than any screen.
RULES
How complex the business rules, permissions and edge cases are.
EVOLUTION
Ongoing maintenance and evolution, which is worth budgeting for from the start.

09 / WHO BUILDS IT

Custom software developers: talk to the person who builds it.

A software house and an architect who writes the code solve different problems. This is the honest dividing line.

Working with me fits if…

You want to talk directly to the person who designs and writes the code, with no account managers in between.
The system is critical to your operations and whoever builds it needs to understand the business.
You’d rather have a small, well-built system than a large project with people rotating in and out.

A software house fits better if…

You need a team of ten full-time people from the first month.
The project needs 24/7 on-call cover with several support staff.
What you mainly need is development capacity for a product your own team designs.

10 / QUESTIONS

Questions about custom software.

What is custom software?

A system designed and built for a company’s specific processes, instead of a generic tool the company has to adapt to. It can be a web platform, an internal application, a CRM or the integration between tools you already use.

What kind of custom software do you build?

Web-based systems for internal and external use: platforms, internal applications, CRMs, back offices, portals and integrations between tools. I work with current, maintainable web technology (Nuxt, Vue, TypeScript, Node, MySQL and PostgreSQL) so the system can be understood, maintained and extended.

When is custom software worth it?

When your process is part of your advantage, or your problem is specific enough that a standard tool forces your team to work worse. If an existing tool solves the problem well, using it is usually the best decision, and I will tell you so.

Software should fit the business

Can it integrate with the ERP, CRM or other tools we already use?

Yes, as long as they offer a way in: an API, a database, exports or files. The first step is to check what each system allows; often the best option is to integrate rather than replace. AtalayaIQ, for example, works on top of the database of the system the company already used, in read-only mode.

Read the AtalayaIQ case study

Who owns the code and the data?

Your company does. The repository, credentials and data belong to you, and the system does not lock you into a tool or a person. This is agreed in writing before the project starts.

A system you can’t evolve isn’t yours

How long does custom software development take?

It depends on scope. What I always recommend is getting a first useful piece into production early, within weeks, and growing from there. A system that’s used from the start gets corrected with real information, not assumptions.

How I work

How much does custom software cost?

It depends on scope, integrations, the state of the data to be migrated and how complex the business rules are. Before quoting, I review the problem and propose the smallest first version that already delivers value.

Are you a custom software company or a freelance developer?

I work as a digital architect: I design the system and write the code myself, bringing in specialist support when a project needs it. You always talk to the person who builds it.

What is a Digital Architect?

Do you work with companies outside Spain?

Yes. I am based in Spain and work remotely with companies in other countries, in English or Spanish. You work directly with me, from the first conversation to the system running in production.

Can AI be added later?

Yes. A system with well-structured data and clear processes is the best foundation for adding AI when it brings something specific. Rocio.com and AtalayaIQ both include assistants that work on their own data.

AI and automation

11 / SAME SYSTEM

Other layers of the same system.

Software, data and AI are not separate services. They are designed to work together.

All systems

Has your business outgrown standard tools?

Tell me the problem, the data, the constraints and the objective. You do not need to know yet what has to be built.

Tell me the problem or email me at andres@andresrl.es