Find what is actually holding the product back.
Product decisions, user behavior, funnels, activation, analytics, experiments, monetization, and complex product problems.
Explore Product & data →I solve difficult
product problems.
Product · Data · Engineering
I’m Alex. I’ve spent 15+ years building mobile products, and I’m very good at this work. I investigate the problem, decide what needs to change, and get it done. From product decisions and SQL to architecture and application code.
Tell me what you’re dealing with ↗See what I’ve done →
Want to see what you’d get? See sample reports →
15+ years building products
Selected professional experience
Samsung Food
Termius
Nebenan.de
Myworkout
PayMaker
Selected professional experience
Samsung FoodTermiusNebenan.deMyworkoutPayMakerSample reports
All sample reports →See what you’d get.
Fictional companies and synthetic data. The same structure and depth as my client reports.
Investigation + implementation · 3 weeksAd revenue kept falling. Three weeks to fix it.
Investigation · 4 daysRegistration loses 75%. Which step should we redesign?
Experiment review · 3 daysThe test said +19%. After rollout, nothing changed.
Investigation · 5 daysRegistrations nearly doubled. Paying users didn’t.
Urgent · 1 dayThe paywall went blank. Do we need an emergency release?
Wondering what access I’d need? How I work with your data →
Selected work
Here’s what that looks like.
App migrations, misleading funnels, ad integrations, and activation. A selection of the engineering work and product investigations behind my experience.
Engineering / KMP ↗
Explore all cases and engineering contributions →They wanted shared code. I defined the architecture and migrated the business logic.
I migrated business logic for iOS and Android to Kotlin Multiplatform, then started moving UI into shared Compose code.
Product / Funnels ↗They had new registration designs ready. I found the problem in the funnel.
The team thought registration was losing 70% of users. I rebuilt the funnel and investigated the different paths. The step they suspected was working; the first page and the route to login needed attention.
Engineering / Team lead ↗A whole home in one iPhone and iPad app. I led it from MVP to 1.0.
As lead iOS developer at a smart-home startup, I led a team of up to four developers through the MVP and version 1.0: an offline demo mode, a dedicated iPad experience, encrypted remote access, and real-time sync with the home’s hardware.
Product / Experiments ↗Their A/B test winner performed worse after rollout. I investigated why.
An independent article nobody knew about brought a surge of downloads during the test. I separated that cohort and found that the control performed better for the remaining organic traffic.
Engineering / Production incident ↗Four hidden bugs. A broken iOS feed. An emergency release avoided.
The home feed went blank and ads turned white. I traced four defects across SwiftUI, an ad SDK, and bidder configuration, contained the immediate ad failure across app versions, and fixed the underlying code.
Product / Research & experiments ↗I worked through onboarding, product questions, and measurement for a fitness app.
I improved registration, introduced Jobs to Be Done and regular product-health metrics, ran onboarding experiments, investigated demand for social features, and reviewed tracking.
Alex Severianov / Founder, X91 TechThe person behind the workProduct, data, and code.
Product, data, and code.
One person.
I’ve spent 15+ years building products across consumer apps, social networks, fitness, payments, and smart-home systems.
I’m comfortable in the product discussion, the database, and the codebase. I investigate user behavior, challenge assumptions, and build across iOS, Android, Flutter, and Kotlin Multiplatform.
I run X91 Tech. Work with me and you work directly with the person doing the investigation and implementation. I listen carefully, tell you what I think, and take responsibility for my work.
More about Alex →What I take on
From figuring it out to getting it done.
You may only know something is wrong. You may know exactly what needs building. I work from either starting point.
Build, modernize, or untangle complex products.
Mobile and desktop development, architecture, Kotlin Multiplatform, migrations, integrations, CI, and difficult engineering work.
Explore Development →Don’t know what to build or fix next? That’s a problem too. I investigate what’s holding the product back, what deserves attention, and how we’ll know it worked.
Independent work / X91 AppsI also build
I also build
my own products.
Alongside my professional work, I design and build independent products. That means working through scope, implementation, release, and the decisions that follow.
X91 Apps is the home for that side of my work.
Explore X91 Apps ↗Let’s talkBring me
Bring me
the problem.
An app that needs building. A migration that needs someone to own it. Numbers that don’t make sense. A product decision your team can’t resolve. Tell me what’s happening. I’ll tell you whether I’m the right person, how I’d approach it, and what the work would cost.
Email Alex ↗alex@x91tech.comYou bring the context. I take the work seriously.
Not sure what you’d get? See sample reports →