Eight platforms, one codebase

A mobile app developer who has shipped to every store that matters

React Native wrappers for iOS and Android, Electron for macOS, Windows and Linux, a Chrome extension, installable web apps. Eight platforms for one SaaS, an email client in the iOS and macOS App Store in four months, and 25+ apps with 3.7 million downloads before that.

Book a free 30-min call Email me instead

Available from November 2026 · Wrocław, Poland (CET), remote

“someone you can always count on”public LinkedIn recommendation
“a true bias for action”client CTO, on LinkedIn
15+ yearsshipping software
Free call, no pitch deck30 minutes, then you decide

8platforms shipped for Sandtime.io as founding engineer

4months from first commit to the App Store

25+apps shipped, 3.7M+ downloads (2009 to 2017)

15+years shipping software

Web first, native where it pays

One codebase, one release train. Native modules only where the web cannot do the job: system tray, background sync, store subscriptions. The demo below shows what your device supports right now.

Store review is a process, not a lottery

Privacy manifests, sign-in rules, subscription receipts, CASA for OAuth mail access, Yahoo’s OAuth review. I have been through them and keep the checklists.

Accessible on a phone too

WCAG 2.2 AA behind an automated gate, 200% text scaling, a calm mode for older users. Shipped, tested on every release.

Measured on every platform

The same PostHog events on web, desktop and mobile, so the dashboard answers “which platform converts” instead of “we think iOS”.

Proof

Work I can show

Problem, what I did, result. Client names only where I am allowed to use them.

Sandtime.io: founding engineer, eight platforms, one codebase

The problem: A time-tracking SaaS had to live where people work: desktop tray, browser, phone and app stores.
What I did: I authored the original product vision and architecture in 2018 and made the first commit. React Native wrappers for iOS and Android, Electron for macOS, Windows and Linux, a Chrome extension, multi-tenant routing, SSO, Dockerized services, Paddle and Mac App Store subscriptions, CI/CD.
Result: Eight platforms shipped and run in production. The only engineer active in every year of the product, 8,000+ commits and close to half of all merges to trunk.

8 platforms 8,000+ commits since 2018 Open ↗

See also: SaaS & MVP · Maintenance & CI/CD

Patriot Mail: from first commit to the App Store in four months

The problem: A greenfield AI-native email client for web, iOS and macOS had to reach real users fast, pass Google’s CASA Tier 2 security assessment and work for older people.
What I did: I was the principal engineer. I wrote the delivery plan, shaped the product vision and treated prompt injection through untrusted email as a design constraint before any model touched a mailbox. CASA and OWASP ASVS controls became a Playwright suite that runs on every pull request. WCAG 2.2 AA sits behind an automated axe gate.
Result: Public App Store release in four months. CASA Tier 2 passed and the yearly questionnaire turned into a check on every PR. Text scaling to 200% and a calm-email mode shipped for older users.

4 months CASA Tier 2 WCAG 2.2 AA Open ↗

Omio: ads and ancillaries across web, React Native apps and email

The problem: Ad experiences had to ship consistently across web, native apps and email in a data-driven, OKR-based organization.
What I did: I owned features end to end: design, implementation across repositories and platforms, A/B tests and monitoring. Open redirects found on the way were reported.
Result: Consistent delivery under an OKR regime across web, React Native, Android and iOS.

A/B tests React Native OKR

Not ready for a project? Start smaller.

Two ways to see how I work before you commit to a sprint. Fixed scope, a number in writing after a short call.

Mobile & desktop apps codebase audit, one week

I read the repo, CI, tests, security and the parts the team avoids. You get a written report with findings ranked by risk, a plan with milestones and a go or no-go you can defend. I have run this for a large software house before its clients saw the code.

Code review of one pull request or one module

Send me the diff that worries you. Within a few days you get line-level comments, the three things I would change first and whether I would merge it.

Ask about an audit Free 30-minute call first. If an audit is the wrong tool, I say so on the call.

Live demo

Your device, probed live

The demo asks your browser what it can do: install as an app, run a service worker, share, badge the icon, push, read files. Then it draws the capability matrix across web, PWA, Electron, React Native and native, with your own column highlighted. Nothing is sent anywhere.

Demo loading…

Open this page on your phone and compare. The install button appears when the browser allows it.

How it works

Three steps from this page to a running project.

1
A 30-minute call
You describe the product and the problem. I ask the questions I would ask on day one. If I am not the right person, I say so and point you to someone who is.
2
Scope in writing
A short written plan follows: what we build first, what we measure, how we work together and what it costs. No slide deck.
3
Something to touch in week one
The first slice ships in the first week: deployed, measured, reviewable. From there the work is paced by what the numbers say.

Book a free call Email me instead

Fit check

Is this a fit?

A good fit when

You need a senior who owns delivery, not a pair of hands
The product has to ship and be measured, with or without a product manager
A solo engagement or a team of up to four
TypeScript, React, Node.js, Cloudflare, Postgres, PostHog

Probably not when

A program that needs a ten-person vendor team
A stack built around Java, Python or a cloud I do not sell
Body leasing by the hour with no say in how the work is done
A start before November 2026

Working style

How I work

Zero bug policy

A bug is fixed or consciously closed, never parked. Alerts and error tracking in every project, so I learn about problems before the client does.

Review as a craft

Hundreds of pull requests reviewed. I review for the product and its reasons. The code comes second.

Measured, not assumed

PostHog in every project from day one. A tracking plan per feature and dashboards leadership actually reads.

FAQ

Questions people ask before they book

React Native or native Swift and Kotlin?

React Native when the team is web-first and the app is mostly screens and data. Native when the product is the hardware: camera pipelines, audio, heavy background work. I have shipped React Native to both stores and know where it hurts. The web side of that story is on the React page.

Is Electron still a good idea?

For desktop apps that need a tray, a window and the file system, yes. It shipped a time tracker to macOS, Windows and Linux with one codebase. The size is a cost, the velocity is the gain. For the pure-web route see the JavaScript page.

How painful is App Store review?

Painful once, then a checklist. Privacy details, sign-in parity, subscription flows, screenshots, review notes. I keep the list current and pass on the first try more often than not.

Chrome extension?

Shipped one for a time tracker. Manifest V3, a service worker, the same login as the web app, Web Store listing included. The same codebase runs as a SaaS on the web.

Do you do apps from scratch or take over?

Both. Taking over starts with a build that passes on my machine, a signing audit and a release to TestFlight within the first week.

How soon can you start?

November 2026. Book the call and bring the store accounts.

Let’s find out in 30 minutes

A free 30-minute call. You bring the problem, I bring questions. No prices on this page because scope comes first.

If I am the wrong person I will say so on the call and point you to someone better.