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Team Extension · .NET · JavaScript
Two more senior engineers in your team in two weeks
Hiring a senior .NET or JavaScript developer takes months. Our engineers join your stand-ups, your repo and your tools within two weeks, and work like part of your team. That’s how 3 of our people have worked with Privalgo for 2.5 years.
Team Extension in practice
Boutique teams, inside our clients’ teams
Three engagements where 3 of our engineers joined the client’s team.
Solution components in a business-critical Dynamics 365 CRM, cleaned up by 3 of our engineers. 2.5 years in, and still going.
PrivalgoUnited Kingdom
A new release of EF Studio every month for a year. 3 engineers modernising a platform used by 20,000+ people.
EF Education FirstSwitzerland
Unhandled incidents from around the world, moved from Excel into ServiceNow ITSM in 9 months by a team of 3.
CiscoUnited States & United Kingdom
When it fits
Your roadmap is bigger than your team
Team Extension is for engineering leaders who need more senior hands now, without a six-month hiring process or handing their product to an outside project team.
- You have a backlog and deadlines, but not enough senior engineers to deliver them.
- Hiring takes months and the market for senior .NET and JavaScript people is thin.
- You want to keep ownership of the product, architecture and process.
- You need people who can work in an existing codebase from the first sprint.
- You want to scale the team up or down without long-term headcount.
How it works
From first call to first commit in two weeks
Call (30 min)
You tell us your stack, team and the gap you need to fill. We tell you honestly whether we are a fit.
Profiles in 2 days
Hand-picked senior engineers matched to your stack and seniority needs, not a stack of CVs.
You interview
You meet every candidate and approve who joins your team.
Start in your sprint
Onboarding into your tools and rituals. We stay accountable for quality and continuity.
Who can join your team
Not just developers
.NET & C# engineers
Backend, APIs and web platforms in .NET, including work on existing .NET Framework systems.
.NET Development →JavaScript & TypeScript engineers
Frontend and full-stack work in Angular, TypeScript and Node.js.
.NET & JavaScript Development →Dynamics 365 developers
Plugins, customisation, integrations and solution clean-up in Dynamics 365 CRM.
Dynamics 365 →Business & system analysts
People who turn business needs into clear, testable requirements for your team.
QA engineers
Manual and automated testing so quality does not depend on developers alone.
Project managers
Delivery support when you need someone to keep scope, timeline and reporting on track.
What you get
Why teams extend with Appstronauts
- 01
Senior by default
People who make decisions, not people who need them made. You interview everyone before they start.
- 02
You keep control
Your product, your architecture, your process. Our people work as part of your team, not as a separate vendor team.
- 03
Continuity is on us
Holidays, sick days and replacements are our job. We plan handovers so your sprint keeps moving.
- 04
Founder-level attention
We are small enough that Rado knows every engagement, and big enough to grow your team when you need it.
FAQ
Questions we hear most
How fast can engineers join our team?
We send hand-picked profiles within 2 days of our first call. Once you approve the people, they usually join your sprint within two weeks.
Do we interview the engineers?
Yes. You meet every person before they join and nobody starts without your approval.
Who manages the engineers day to day?
They work in your process: your stand-ups, your backlog, your repo and your tools. We stay responsible for their performance, holidays, replacements and quality.
What happens if someone leaves or is not a good fit?
We replace them. Continuity is our responsibility, not yours, and we plan handovers so your sprint does not stop.
How is Team Extension billed?
Monthly, on a Time & Material basis. You pay for the time our people work in your team, with no recruitment fees.
Which time zone and language do your engineers work in?
Central European Time, in English, and in German where your team needs it. That gives a full working-day overlap with DACH and most of the day with the UK.
How do you use AI?
Our engineers work with Claude and Cursor in practically every project. It roughly doubles their output and shortens delivery by up to 40%, with the same savings on cost. Senior engineers stay in charge of architecture and review every AI-assisted change, and we agree with you up front which tools and models may be used on your code and data.
How much does it cost to work with you?
It depends on the seniority and the number of people you need. Team Extension and dedicated teams are billed monthly on Time & Material, with no recruitment fees, and most clients start with one or two engineers. Proofs of concept and clearly scoped projects can be done for a fixed fee. After a 30-minute call you get a concrete proposal with rates for the profiles you need.
Security & trust
Ready for your procurement and security review
We work with companies like Cisco and EF Education First, so the paperwork is part of the job. Whatever your policies require, we sign and follow.
NDA, before anything else
We sign your NDA before you share anything about your project.
Data Processing Agreement
A GDPR-compliant DPA whenever we process personal data on your behalf.
Professional liability insurance
Our work is covered by professional liability (OC) insurance, with details for your procurement team on request.
Your hardware, your accounts
If your security policy requires it, our engineers work only on your laptops, VPN and accounts.
Certified engineers
Most of our engineers hold Microsoft, AWS, Google Cloud or Claude certifications.
AI on your terms
We agree up front which AI tools and models can be used on your code and data, and nothing else is.
Verified on Clutch
What it’s like to have our engineers in your team
From clients who extended their teams with Appstronauts.
“We are impressed by their approach, professionalism, confidence, and agility.”
Verified review on Clutch · 5.0 · Staff augmentation · since 2020
“We had a good experience, thanks to their open-mindedness and outstanding ideas.”
Verified review on Clutch · 5.0 · Staff augmentation
“Communication with Appstronauts was so transparent that we really felt like they were part of our team.”
Verified review on Clutch · 5.0 · Finance app development
Let’s talk
Need senior engineers on your team?
Book 30 minutes with me. Tell me your stack and the gap you need to fill, and I’ll tell you honestly whether we can help and how fast.
or email radek@appstronauts.co