Available for new engagements & takeovers

~/stembera $ whoami

Stanley J. Stembera

Freelance Senior Full-Stack Developer helping teams regain control of legacy, messy, or stalled software projects — from architecture and migrations to stabilization and hands-on delivery.

Typical stack: TypeScript, JavaScript, React, Node.js, Electron, SQL, legacy frontend/backend systems.

Typical situations I help with: legacy code that nobody wants to touch, migrations that lost direction, systems that became fragile over time, and projects that got stuck halfway through.
Takeovers
legacy, stalled, complex systems
10+
years in enterprise delivery
18
selected enterprise clients
4
languages spoken

About

I help teams take control of software that became difficult to maintain, hard to understand, or risky to change — whether that means stepping into a legacy codebase, stabilizing an unreliable system, or helping a project regain direction.

I build and shape applications end-to-end — from user interfaces and interaction flows to backend services, data models, and overall system architecture.

I’m typically brought in when a system needs to be rethought, stabilized, or gradually transformed — whether that means migrating legacy code, defining a clearer architecture, or helping teams find direction and confidence in their codebase.

My background includes long-running enterprise work for organizations such as ESA, Airbus, BMW, Deutsche Bank, and others where reliability, continuity, and technical clarity matter over time.

I often work alongside developers as well, helping teams raise the overall level of engineering within a project through practical guidance, code reviews, and day-to-day technical clarity.


Focus

Architecture & direction

Defining clearer system boundaries, reducing accidental complexity, and helping projects move toward structures that make sense long term.

Legacy migrations

Gradual modernization of legacy applications without losing control of the system, the data, or the team around it.

Stabilization & cleanup

Taking systems that have grown messy over time and turning them into something more predictable, maintainable, and easier to reason about.

Takeovers

Stepping into projects after previous developers, rebuilding understanding of the system, and helping teams regain confidence in how to move forward.


Clients

Selected clients across aerospace, finance, telecom, manufacturing, retail, and software.

European Space Agency (ESA)Aerospace
AirbusAerospace
BMWAutomotive
Deutsche BankFinance
HSBCFinance
AllianzInsurance
AppleTechnology
MicrosoftSoftware
Nokia Siemens NetworksTelecom
Deutsche PostLogistics
OSRAMIndustry
FoxconnManufacturing
1&1 InternetInternet
Yettel BulgariaTelecom
Haufe-LexwareSoftware
DekaBankFinance
SinnerSchraderAgency
DouglasRetail
Aerospace Finance Telecom Automotive Manufacturing Retail Software

Contact

If your project got stuck, became hard to maintain, or lost direction over time, I can help you get it back under control. Whether you need someone to step in, stabilize the system, or help move a difficult project forward — feel free to get in touch.

Currently available for new project work.

Karlstein am Main, Germany · Remote & on-site · DACH + CZ