Customsoftware,ready tomonetize.
Technology experts and lawyers on one team. We build your app or platform and handle the legal side, so you can sell it, license it or raise capital with no surprises.
What usually goes wrong, and how we prevent it
If you've hired a software team before, some of these will sound familiar. If this is your first project, these are the ones to avoid.
The code isn't in your name
You paid for the build, but there's no written contract saying who owns the software. Without one, the rights are presumed to belong to whoever wrote the code, not whoever paid, and selling it, licensing it or showing it to investors turns into a dispute.
How we solve it: Yours or licensed, in writing
Before we start we sign the arrangement that fits: work made for hire, assignment of rights or license, depending on your business model. It's in writing from day one, so you know exactly what you can do with it.
Your software ends up in someone else's hands
The domain, server, code repository or app store account is in the developer's name, or you only got the app without its source code. If the relationship breaks down you can't even update it: in practice, you've lost your software.
How we solve it: Everything in your name, from day one
Domain, servers, repository and App Store and Google Play accounts are opened in your company's name. With every release you get the source code, the documentation and the credentials.
Budgets and timelines spiral
The project starts without a clear scope, and every week something new comes up that costs more and pushes delivery back.
How we solve it: Clear scope before we start
You know what will be built, in what order and what it costs. Then frequent releases you can test: you see real progress, not reports.
You talk to a salesperson, not the builders
Your ideas pass through several hands before reaching the technical team, and details get lost along the way.
How we solve it: Talk to the people writing the code
No middlemen: you deal directly with the team designing and building your project.
Off-the-shelf software makes you adapt
You end up bending your operation to a tool that wasn't made for you, or patching the gaps with spreadsheets.
How we solve it: Built around how you operate
We start from your processes, rules and integrations, so the system fits your business, not the other way around.
Legal comes late, or never
The software ships without contracts, terms or a privacy notice, and the gaps show up right when you want to sell it, license it or raise capital.
How we solve it: Lawyers on the same team
With ANBEC Abogados we prepare contracts, licenses, terms, the privacy notice and registration filings with INDAUTOR and IMPI while we build.
The system can't keep up as you grow
More users, more data or one new feature, and something gives. Nobody wants to touch the code for fear of breaking it.
How we solve it: Built to grow
Architecture and tests designed so the system holds up to what's next, with support and improvements as your business grows.
What we build
One team for the whole journey: product, design, code, infrastructure and the legal side.
Systems built around how your company actually runs: processes, rules and integrations no off-the-shelf product handles.
- Internal systems, custom CRMs and ERPs
- Automation of manual processes
- Integrations with APIs, payments and existing systems
- Dashboards and reporting
Fast, stable iOS and Android apps, ready to ship to the stores.
- Native and cross-platform apps
- App Store and Google Play release
- Notifications, payments, maps and camera
- Backend and admin panel
Complete web products, from a customer portal to a platform with users, payments and administration.
- SaaS platforms and digital products
- Customer and supplier portals
- Custom e-commerce
- Fast, accessible, search-friendly websites
Usually one team builds the software and another handles the legal work, and details fall through the cracks. Here lawyers and technology experts work on the same project, so what gets built and what gets signed say the same thing.
- Work made for hire, assignment of rights or software license
- Development, maintenance and SaaS agreements
- Terms of service and privacy notice
- Software copyright (INDAUTOR) and trademark (IMPI) registration in Mexico
- Monetization models: licenses, subscriptions and resale
From idea to launch, no detours
Every project follows the same route. You always know which station we're at and what comes next.
Understand
We listen to the problem, your users and your goals. We define scope, priorities and a clear estimate.
LegalWe identify what needs protecting from the start.
Design
Prototypes you can touch and an architecture thought through before the first line of code.
LegalWe set the arrangement in writing: work made for hire, assignment or license.
Build
Frequent releases you can test. You see real progress, not reports.
LegalWe review the licenses of the open source we use.
Launch
We ship with tests, monitoring and everything ready for real users.
LegalTerms, privacy notice and registrations in order.
Evolve
Support, improvements and new features as your business grows.
LegalAgreements to license your software to third parties.
Technology and law at the same table
We build your software and leave it protected. At the end you don't just get a repository: you get a complete legal and technical file.
- 01Source code and technical documentation
- 02Work-made-for-hire, assignment or license agreement
- 03Copyright registration filing with INDAUTOR
- 04Trademark application with IMPI
- 05Terms of service and privacy notice
- 06Open source license review
Contents are defined by the scope of each project.
Technologies we work with
- TypeScript
- React
- Next.js
- Astro
- Node.js
- Python
- Swift
- Kotlin
- Flutter
- Expo
- PostgreSQL
- MongoDB
- Redis
- GraphQL
- Firebase
- Supabase
- Google Cloud
- Docker
- Vercel
- Stripe
- Tailwind CSS
- Figma
Work
Our own products, designed, built and run by us, legal side included.
Producto propio · slexapp.com
SLex
Platform for law firms: clients, matters, deadlines, documents, e-invoicing and court case tracking.
Automated court monitoringCalculated deadlinesE-invoicing- Web platform
Producto propio · somosmarkus.com
Markus
Assesses whether a trademark can be registered with IMPI, handles the filing with online payment and tracks the process.
AI trademark assessmentOnline paymentFiling tracking
Why Rex?
RexDevs is named after Rex, our founder's dog.
We put him in the name and the logo as a reminder of what we want to be for every client: loyal, attentive and there every day. Every project has people behind it, and that's how we treat it.
Frequently asked questions
What people ask us most before starting a project.
What kind of software does RexDevs build?
Custom software: iOS and Android mobile apps, web and SaaS platforms, client and vendor portals, and internal systems such as CRMs and ERPs, with their integrations and automations. Everything is built around how your business operates, not from templates.
Who owns the code when the project ends?
It's set out in a written contract before we start, because without one the rights are presumed to belong to whoever writes the code. For custom software we normally agree on a work made for hire: with clear and precise terms, the economic rights are yours from the moment each deliverable is created (articles 83 and 83 bis of Mexico's Federal Copyright Law). If the product already existed, we use an assignment of rights; if you prefer a lower cost, a license. They're different arrangements, and we explain which one fits your business model.
Can you register my software with INDAUTOR and my trademark with IMPI?
Yes. Together with ANBEC Abogados, our allied law firm, we prepare the copyright registration of your software with INDAUTOR and your trademark application with IMPI, plus contracts, licenses, terms and conditions and the privacy notice. The legal work is signed and backed by ANBEC Abogados.
How much does it cost to build an app or a web platform?
It depends on the scope: number of screens, users, integrations and the legal work you need. Before we start we define what gets built, in what order and what it costs, and you receive a single proposal covering the software and the legal side. Write to us with your idea to get an estimate.
What does the process look like?
Five stages: understand the problem and define the scope, design prototypes and architecture, build with frequent releases you can test, launch with testing and monitoring, and evolve with support and new features. You deal directly with the team that designs and writes the code.
Where is RexDevs and who do you work with?
We're based in Colonia Anzures, Mexico City. We work with founders building their first product, small and mid-size businesses digitalizing their operations and companies looking for an external engineering team, in Spanish and English.
What have you built?
Our own products, which we design, build and operate: SLex (slexapp.com), a platform for law firms with automated court monitoring, calculated deadlines and e-invoicing, and Markus (somosmarkus.com), which uses AI to assess whether a trademark can be registered with IMPI and handles the filing with online payment.
What do you want to build?
Tell us about your idea or your problem. We reply personally.
Or write to us directly
Emailhola@rexdevs.com