Mojave is now Paying.co — same team and expertise, now with a name that reflects our core mission. Learn more →
Custom Development

Ship what you need. Faster than you thought possible.

Custom software, payment applications, mobile apps, AI tools, legacy modernization. Our 100+ engineer team has been doing this for 30+ years across four continents — which means we hit the ground running on your project with little to no ramp-up time. The work that takes most teams quarters takes us weeks. The work that's been stuck on your internal roadmap for years can ship this quarter.

100+
In-House Team
30+
Years Experience
15+
Languages & Stacks
0
Ramp-Up Time
What We Build

Custom software, end-to-end.

Discovery to deployment, with everything in between handled by the same team. We specialize in payment technology because that's where our 30+ years live, but our engineers ship across every vertical and every layer of the stack. If it compiles, we've shipped it.

code

Any language, any platform

C/C++, Java, Python, JavaScript, TypeScript, Swift, Kotlin, Go, Rust, COBOL when we have to. Legacy mainframes, embedded firmware, native mobile, modern web, serverless cloud — we have engineers who've shipped to all of it, and we deploy them to your project, not a sales pitch.

smartphone

Mobile, web & embedded

Native iOS and Android, cross-platform with Flutter or React Native, embedded systems on PAX, Ingenico, Castles, Sunmi, and Clover, payment terminals down to the kernel layer. The right tech for the job, not a one-stack-fits-all answer.

upgrade

Legacy modernization

Your business runs on a system that's older than half the team that maintains it. We migrate, refactor, and re-platform without losing the institutional knowledge baked into the original. Modern technologies, better performance, the same business logic that earned you your customers.

construction

Custom software, the specialty

The build that doesn't fit a template. The integration nobody else wants to touch. The workflow that's specific to your business and would never be a SaaS product. That's the work we do best — and the work that creates the most durable competitive advantage for the teams we build it for.

Success Stories

Three projects. Three sizes. One pattern.

The same speed-to-market, the same depth of bench, the same hit-the-ground-running engineering — whether the engagement is a focused build for a startup, a complex platform for a mid-market operator, or a global rollout for an enterprise. Names are anonymized, outcomes are real.

rocket_launch Small Company

Fintech Startup, MVP to Live

Mobile app · Payment integration · Compliance

A pre-seed fintech needed a working mobile app, a payment integration, and enough compliance scaffolding to demo to investors — in eight weeks, end-to-end. We staffed up day one with no ramp, shipped the MVP in seven, and helped them close their seed round on the back of a working product instead of a slide deck.

7 wks
MVP to Live
$3M
Seed Round Closed
trending_up Mid-Market

Payment ISO, Platform Rebuild

Legacy modernization · Multi-processor · Web & API

A growing ISO's internal team had been working on a platform rebuild for two years and was still six months out from a beta. They brought us in. We picked up the existing codebase, redesigned the architecture, and shipped a production-ready platform — with new processor integrations, a redesigned merchant portal, and a clean API — in five months total.

5 mo
Shipped (vs. 2+ years)
4x
Faster Than Internal
business Enterprise

Global Payment Operator

Multi-country rollout · Embedded · 8 processors

A Fortune 1000 payments operator needed a unified terminal application rolled out across eight processors in five countries, with localization, compliance variations, and regional certification all in play. We staffed a 22-engineer cross-functional team, ran four parallel workstreams, and delivered the full rollout in nine months — six months ahead of their original internal target.

9 mo
Multi-Country Rollout
6 mo
Ahead of Schedule
Why Paying.co

A team that's already shipped this.

Most of what you'll ask us to build, we've built before — for someone in your industry, on the same kind of stack, against the same kind of deadline. That's why we ramp in days instead of months, why our rates are competitive without compromising on senior engineering, and why the sky really is the limit on what we can take on. The bench is deep, the experience runs decades, and the cost of getting it wrong somewhere else is the cost you don't pay with us.

100+
Engineers, Designers, QA, PMs
30+
Years Combined Experience
4
Continents Served
0
Ramp-Up Time
Our Process

A proven approach to shipping on time.

Four stages, run in parallel where they can be, sequential where they have to be. No surprises, no scope drift, no project manager telling you the bad news a week before launch. The team you brief is the team that ships.

forum

Discovery & scoping

We map your requirements, technical constraints, and goals into a fixed-scope SOW with a defined timeline and named owners on both sides. No code gets written until we both agree what we're building.

architecture

Design & architecture

Wireframes, UX, system architecture, technology selection. We pick the stack that fits the problem, not the stack we know best. The deliverable is a build plan you could hand to any engineering team.

build

Development & QA

Agile sprints with continuous integration, embedded QA from day one, and demos at the end of every cycle. You see progress weekly, not on milestone day. Issues found early are issues that never reach production.

rocket_launch

Deployment & support

We handle production cutover, monitoring, and ongoing maintenance. Updates, performance optimization, feature enhancements — we stay on as long as you want us to. The relationship doesn't end at go-live.

Ready to Get Started?

Let's build something great.

Tell us what you're trying to build. We'll come back with a scope, a fixed price, and a realistic timeline — usually within 24 hours. You'll hear back from an engineer, not a sales rep.

schedule
Response within one business day Most projects start with a 30-minute scoping call
engineering
You'll talk to an experienced sales engineer The person you brief is the person who scopes your build
handshake
No-obligation feasibility review We'll help you scope it and determine the best path forward that matches your budget and timeline
language
We speak your language English, Spanish, and Polish — fluent across our team and project leads
bolt
Little to no ramp-up time We've shipped what you're asking for — bench is deep, learning curve is short
Start a Conversation

What's been stuck on your roadmap? Let's ship it.

Tell us about the project. We'll come back with a scope, a fixed price, and a realistic timeline based on what we've built before for teams like yours — usually within 24 hours. Free, no obligation.

schedule Quote returned within 24 hours · Fixed-scope · No surprises