Let's Build What Matters
Partnering with mission-driven, early-stage teams on the engineering, growth, and AI automation that moves the mission forward.
Services
End-to-end engineering for products that need to work at scale.
AI Engineering
AI-powered products that go beyond chat interfaces: agentic workflows, RAG pipelines, NLP systems, and intelligent automation that delivers real business value.
Full-stack Web Applications
Full-stack web applications built for scale. From SaaS platforms to ecommerce systems, production-grade software that handles millions of users.
Native App Development
Native and cross-platform mobile apps that users love, from a #1 App Store launch to apps serving users across five countries.
Data Engineering
Scalable data pipelines, ETL systems, and search infrastructure: the plumbing that powers data-driven products and real-time analytics.
Analytics & Experimentation
Instrumentation that answers real product questions. Event tracking, conversion funnels, and a disciplined experimentation practice, from planning tests to analyzing results.
User Acquisition
Paid and organic growth channels. Google Ads, SEO, AEO, keyword research, and content planning, including LegitScript certification for healthcare and other regulated advertisers.
How It Works
From first conversation to shipped product in three steps.
Intro Call
Discussing your needs
We'll talk through what you're building, where you need help, and what success looks like.
Assessment
Review and map solutions
A review of your current stack and workflows, followed by a clear scope of work to meet your goals.
Deliver
Build and ship
The work gets built and shipped as a focused project or an ongoing retainer, depending on your needs.
Portfolio
Products built, teams led, and companies scaled.
Fullsend Technology
Co-Founded & Built
AI-native content automation for small businesses. Built agentic workflows that surface keyword opportunities, generate SEO-optimized content, and publish directly to websites and social channels.
Joymode
Engineering & Growth Lead
An on-demand product rental platform helping people do more while owning less. Joined as a full-stack engineer and quickly grew to lead engineering and product on the Growth team.
Built by an Engineer Who Ships
Control Flow Technology is a software consultancy founded by Matthew Montanez, a senior engineer and technical leader with over fifteen years of experience building products that scale.
Matthew has co-founded startups, led engineering teams of eight-plus, and shipped products used by millions of people across five countries. Two of those companies were acquired. One app hit #1 in the US App Store.
The work goes beyond writing code: building the systems, teams, and infrastructure that turn ideas into products people rely on.

Frequently Asked Questions
Answers to common questions about working together.
Founder-led and senior-only, with no sales team handing you off to junior devs. You work directly with an engineer who has built and sold companies, led engineering teams, and operated at scale.
It starts with a call to understand what you're building and where you need help. From there, the work gets scoped and building starts. No 6-month discovery phases, no 50-page strategy decks, just fast execution from someone who's done this before.
Both. The experience spans co-founding startups from scratch and leading engineering at companies with millions of users, so whether you're pre-launch or scaling, you get someone who knows what good looks like at every stage.
Stack-flexible, with the deepest experience in Python, Django, React, Vue.js, Swift, and AWS. The right tools for the job, not a one-size-fits-all approach.
Both project-based and retainer engagements are available, depending on what you need. Some clients start with a focused build; others keep an ongoing engagement for continuous development and technical leadership.
Ready to Build?
Whether you need a full product built from scratch, an engineering team scaled, or an AI strategy that actually ships, let's talk.