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Fiverr Pro
English
$
USD
I will build or fix your dotnet or node API integration
Andrew Carl
About this gig
Work directly with a Pennsylvania-based senior engineer and U.S. citizen with 17+ years of experience. I moved about $1M a year in payments to a new fee model with zero downtime, and I build integrations that keep working after handoff.
Choose a package for your working C#/.NET or Node.js/TypeScript app:
Basic, API fix: I diagnose and fix one failing API call or webhook and send a short root-cause note.
Standard, one API integration: one documented service and one business action, such as sending a lead to a CRM or importing an order, with validation, retries, duplicate protection, tests and setup notes.
Premium, API workflow: one workflow with up to 3 related actions (for example, order to CRM plus accounting), with tests and a staging handoff.
You own the accounts, keys and infrastructure and pay vendor and testing costs. I guide secure setup. We agree the data mapping, trigger and success and failure cases first.
New apps, auth foundations, migrations, two-way sync and production release need a custom offer. Message me before ordering.
Get to know Andrew Carl
Andrew Carl
Backend Engineer, Dotnet, APIs and AI Data Pipelines
- FromUnited States
- Member sinceFeb 2022
Languages
English
I'm Andrew, a US citizen and backend engineer based in Pennsylvania with 17+ years of software experience. I build and repair C#/.NET services, API integrations, SQL workflows and practical AI data pipelines.
My work includes production SaaS APIs and payments, a Gemini/OpenAI pipeline processing 100,000 profiles, and enterprise integrations at BlueModus. I bring clear scope, tested code and practical handoff notes to each project.
My Portfolio
FAQ
Who builds the work and owns the accounts?
I am a U.S. citizen based in Pennsylvania with 17+ years of software experience. I personally build and review your delivery. You own infrastructure, accounts and keys and pay all hosting, subscriptions, API and testing costs. I guide secure setup.
How are scope, timing and revisions agreed?
Message me before ordering to confirm scope, access and acceptance checks. Delivery is 3 days for Basic, 7 for Standard and 14 for Premium. Each package includes one consolidated revision. New features need a separate quote. I fix defects against the agreed acceptance checks.
Which package fits my project?
Basic fixes one failing call or webhook in existing code. Standard connects one service with one action, including batching, retries and duplicate protection. Premium links up to 3 related actions. More services or unknown API foundations need a custom offer.
Are troubleshooting and handoff included?
Yes. Basic is a focused fix for one failing call. Standard and Premium include one 30-minute handoff and seven days of setup questions, capped at 30 minutes. In-scope defects are fixed. Broad investigations, migrations and production deployment need a custom offer.
