RSApps
Menu

Available now

Your Flutter product, owned end to end.

Architecture, releases, observability and support after launch, delivered by one senior engineer accountable for the result.

Book a call See the work
apps
4
packages
14
dart_loc
~59,000
test_loc
~12,000
ci_workflows
6
ota
shorebird
observability
posthog, crashlytics
payments
przelewy24

// One senior engineer. Your whole Flutter stack.

years of experience
6+
lines of Dart in one monorepo
~59k
lines of automated tests
~12k
R&D IoT systems delivered
3

01 / Services

Five ways RSApps takes work off your plate.

Each one comes from delivered projects, not a capability deck.

01

Flutter apps, end to end

One owner for your iOS, Android and web app: architecture, build, release pipeline and support after launch.

  • Architecture, implementation and store publishing
  • CI/CD on Codemagic or GitHub Actions, Shorebird OTA patches
  • PostHog and Crashlytics from day one, support after launch
02

Enterprise Flutter Web

Internal platforms for finance, compliance, inventory and approvals, built on Supabase and PostgreSQL with row-level security.

  • Supabase and PostgreSQL with row-level security
  • Migrations, RPCs and approval workflows
  • Multi-language interfaces
03

IoT systems

Firmware, backend and control app from one engineer, with the formal documentation that R&D projects require.

  • ESP32 firmware
  • Dart backend: Serverpod, MQTT, WebSockets, PostgreSQL
  • Formal documentation for subsidised R&D projects
04

Rescue and audit

Take over a legacy Flutter codebase, find out what is really wrong with it and turn it into something your team can maintain.

  • Takeover of agency or vendor codebases
  • Security and architecture audits
  • Re-architecture into a maintainable monorepo
05New

Fractional Flutter lead

Senior technical ownership one or two days a week, without a full-time hire.

  • Architecture decisions and ownership
  • Code review and mentoring
  • Team lead from architecture to delivery

All services, fit and deliverables

02 / Selected work

Shipped, in production, still maintained.

All case studies
2024 — nowSole developer

Bodyspace

Membership and e-commerce app · App Store and Google Play

~59k lines of Dart, 4 apps, 14 packages

Took over a legacy vendor codebase and rebuilt it as a Clean Architecture Melos monorepo with ~12k lines of tests, 6 Codemagic workflows, Shorebird OTA patching, PostHog and Crashlytics.

  • Flutter
  • Melos
  • BLoC
  • Codemagic
  • Shorebird
  • Przelewy24
App Store Google Play
2026 — nowFlutter Web engineer

SFP Info · Niveau Deuren

Enterprise Flutter Web, via Sienn

Under NDA — details on request Enterprise workflows for compliance, inventory, contracts, finance and invoicing in Flutter Web. 50+ tickets delivered.
Ask about it
  • Flutter Web
  • Riverpod
  • Supabase
  • PostgreSQL
  • RLS
  • EN / NL
2024 — 2026Core contributor

IOHK · Catalyst Voices

Open-source decentralised platform · IOHK, Cardano ecosystem

OSSpublic, multi-package

Proposal builder, workspace, voting and web performance work on the open-source Flutter Web platform of Project Catalyst, as a core contributor.

  • Flutter Web
  • BLoC
  • Melos
  • Web performance
  • CI/CD
Source on GitHub
2026Full software scope

Smart LED lighting system

Subsidised R&D (B+R) IoT project · Signum

Under NDA — details on request The full software scope of a subsidised R&D IoT project: ESP32 firmware, a Serverpod backend and a Flutter control panel.
Ask about it
  • ESP32
  • Serverpod
  • MQTT
  • PostgreSQL
  • Flutter

03 / What the name means

Reliable

Code that keeps working after launch, and problems that get fixed the same day.

tests · observability · OTA patching

Scalable

Architecture that absorbs new apps, brands and developers without a rewrite.

monorepo · packages · white-label

Applications

Real products in real hands, on the stores and running in production.

App Store · Google Play · production web

04 / Engagement models

Four ways to work together. Clear terms from day one.

05 / Process

Every step ends with something you can hold.

  1. Step 1

    Discovery call

    We talk through your product, team, timeline and constraints.

    You receiveA straight answer on fit and next steps within one business day.

  2. Step 2

    Scope and architecture proposal

    RSApps turns the call into a written plan.

    You receiveScope, architecture outline, milestones and the engagement model that fits.

  3. Step 3

    Build in weekly increments

    Work ships in small, reviewable steps.

    You receiveA demo every week, a test build and a short written changelog.

  4. Step 4

    Release, handover, support

    Store release, then the support you agreed on.

    You receiveReleased app, documentation, full repository access and a support plan.

$ cat how-rsapps-works.md

  • Clean ArchitectureDomain, data and UI separated, so features can change without side effects.
  • Tests as a deliverableUnit, widget and integration tests are in the scope and in the repository you own.
  • CI/CD from day oneEvery commit builds and tests; releases are a workflow, not a ritual.
  • Observability from day oneCrash reporting and product analytics are live before the first release.
  • Written documentationArchitecture notes and handover docs, so you never depend on one person’s memory.
  • AI-assisted workflowClaude Code and MCP tooling speed up the routine work; every line is still reviewed.

06 / Who does the work

Ryszard Schossler

Founder · Senior Flutter Engineer · Rzeszów, Poland · remote

A mechatronics engineer (M.Sc.) who started with mobile and embedded software for R&D IoT projects and has more than six years of experience. RSApps is deliberately one senior engineer: the person on your discovery call is the person who designs the architecture, writes the code and fixes it when something breaks.

English (C1) and Polish (native). Working with teams across Poland and the EU.

LinkedIn GitHub Full story

Have a Flutter product that needs an owner?

Book a call and get a reply within one business day.

Book a call Compare engagement models