Posted 2 Hours Ago Job ID: 2113509 34 quotes received

Senior Full-Stack Developer Needed

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<h1>Senior Full-Stack Developer (FastAPI + PostgreSQL + Multi-Tenant SaaS)</h1>

<h2>Project: TaxNGOHealth Cloud Platform</h2>


<p>

We are building a multi-tenant SaaS platform called

<strong>TaxNGOHealth Cloud Platform</strong> that supports three operational verticals:

</p>


<ul>

  <li><strong>Tax Practice Management (USA)</strong></li>

  <li><strong>Healthcare / Revenue Cycle Management (RCM)</strong></li>

  <li><strong>NGO / Fund Accounting (Global)</strong></li>

</ul>


<p>

A fully developed backend scaffold already exists using

<strong>FastAPI, PostgreSQL, SQLAlchemy, and Alembic</strong>.

We now require an experienced developer or small team to extend the system from

the current scaffold to a production-ready MVP across three phases.

</p>


<hr />


<h2>Repository Documentation (Access Provided After Contract Award)</h2>


<p>Once the contract is awarded, you will receive access to the GitHub repository, which includes:</p>


<ul>

  <li>

    <strong>Development Status:</strong><br/>

    <code>/DEV_STATUS.md</code> — a complete summary of what is finished, in progress, or pending.

  </li>


  <li>

    <strong>Hiring Documentation:</strong><br/>

    <code>/docs/hiring/</code> — includes:

    <ul>

      <li>Job Posting PDFs</li>

      <li>Statement of Work (PDF and DOCX)</li>

      <li>GitHub Project Board CSV</li>

      <li>Jira Epics and Stories CSV</li>

    </ul>

  </li>


  <li>

    <strong>API Documentation:</strong><br/>

    <code>/docs/openapi.yaml</code><br/>

    <code>/docs/openapi.json</code><br/>

    Postman collection under <code>/docs/postman/</code>

  </li>


  <li>

    <strong>Vertical Workflow Documentation:</strong><br/>

    <code>/docs/tax_flows.md</code><br/>

    <code>/docs/rcm_flows.md</code><br/>

    <code>/docs/ngo_flows.md</code>

  </li>

</ul>


<p>The repository is fully structured so that a new developer can onboard efficiently and follow a clearly documented roadmap.</p>


<hr />


<h2>Work Already Completed</h2>


<h3>Platform Backbone</h3>

<ul>

  <li>Multi-tenant architecture (shared DB; tenant isolation in all queries)</li>

  <li>JWT authentication and AuthContext</li>

  <li>Project structure organized by vertical modules</li>

  <li>SQLAlchemy ORM configuration with PostgreSQL</li>

  <li>Alembic migrations with initial schema</li>

  <li>OpenAPI (JSON/YAML) and Postman documentation</li>

  <li>Documentation: DEV_STATUS.md, vertical READMEs, security notes</li>

</ul>


<h3>Tax Vertical (USA)</h3>

<ul>

  <li>Models: Tax Clients, Tax Returns</li>

  <li>Full CRUD endpoints with pagination and filtering</li>

  <li>API alignment with future YOY analytics engine</li>

</ul>


<h3>Healthcare / RCM Vertical</h3>

<ul>

  <li>Models: Claim and Denial</li>

  <li>Full CRUD endpoints with filtering (status, insurer, date range)</li>

  <li>Reporting endpoints (with SQL templates created):</li>

  <ul>

    <li>Claims Aging Report</li>

    <li>Denial Root-Cause Analysis</li>

  </ul>

  <li>Documentation for Denials & Reconciliation Command Center</li>

</ul>


<h3>NGO / Fund Accounting Vertical</h3>

<ul>

  <li>Models: Fund and Project</li>

  <li>CRUD endpoints with filtering</li>

  <li>Fund Utilization reporting structure created</li>

</ul>


<hr />


<h2>Remaining Work (Developer Responsibilities)</h2>


<h3>Phase 1 – RCM Reporting</h3>

<ul>

  <li>Finalize Claims Aging SQL logic using existing CTE templates</li>

  <li>Finalize Denial Root-Cause SQL logic</li>

  <li>Add additional filters (insurer, department, provider)</li>

  <li>Create and optimize database indexes for large datasets</li>

  <li>Add pytest coverage for reporting endpoints</li>

  <li>Update OpenAPI and Postman responses</li>

</ul>


<h3>Phase 2 – NGO Accounting Foundation</h3>

<ul>

  <li>Create <code>fund_transactions</code> model and Alembic migration</li>

  <li>Implement Fund Utilization SQL (fund → project → transactions)</li>

  <li>Add Donor and Grant entities with CRUD support</li>

  <li>Build NGO KPI APIs (utilization, burn rate, restricted funds)</li>

</ul>


<h3>Phase 3 – Tax Analytics</h3>

<ul>

  <li>Build PDF/ProSeries ingestion pipeline</li>

  <li>Extract fields into normalized tax data model</li>

  <li>Create YOY comparison engine</li>

  <li>Build tax analytics APIs (income, credits, refund shifts)</li>

  <li>Complete test coverage</li>

</ul>


<hr />


<h2>Technology Stack</h2>

<ul>

  <li>Python 3.11</li>

  <li>FastAPI</li>

  <li>SQLAlchemy ORM</li>

  <li>PostgreSQL</li>

  <li>Alembic</li>

  <li>JWT authentication</li>

  <li>AWS (deployment environment)</li>

</ul>


<hr />


<h2>Required Skills</h2>

<ul>

  <li>Strong FastAPI and Python skills</li>

  <li>Strong PostgreSQL and SQL optimization skills</li>

  <li>Multi-tenant SaaS development experience</li>

  <li>Experience with Alembic migrations</li>

  <li>Familiarity with pytest and GitHub workflow</li>

</ul>


<h3>Preferred Experience</h3>

<ul>

  <li>Healthcare claims / medical billing</li>

  <li>NGO or fund accounting systems</li>

  <li>Experience with PDF or tax form parsing (ProSeries, Lacerte)</li>

</ul>


<hr />


<h2>How to Apply</h2>

<p>Please include the following with your proposal:</p>

<ol>

  <li>Links to previous FastAPI or multi-tenant SaaS work</li>

  <li>Your GitHub profile</li>

  <li>Confirmation you can complete all three phases</li>

  <li>Your availability and estimated timelines</li>

  <li>Your preferred billing method (milestone-based) and rate for all three phases</li>

</ol>


<p>This is a long-term project with ongoing work across multiple verticals and future AI modules.</p>


<hr />


<h2>About the Client</h2>

<p>

You will work directly with a U.S.-based founder with operations in tax, healthcare, and NGO sectors.

The codebase is organized and designed for sustainable long-term growth and multiple production deployments

across the USA and African markets.

</p>


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Simon K United States