Web GIS Developer Needed to Build Property Tax Mapping Tool

I am looking for a highly experienced Web GIS Developer to build an open-source, browser-based Property Tax Mapping Tool for municipal use. The system will integrate an existing PostgreSQL/PostGIS database with a GeoServer map service and a modern web map interface (Leaflet or similar).

The tool will allow municipal staff to view buildings and community boundaries, click on features to view property details, and enter or update property tax information stored directly in PostGIS.

This is an end-to-end project: system setup, development, testing, deployment, and documentation.

Key Features Required
1. Map & Data Integration

Connect to existing PostGIS database (building footprints, communities, district boundary).

Publish layers using GeoServer (WMS / WFS / GeoJSON).

Apply simple, readable map styling (SLD).

2. Web Application (Frontend)

Interactive map built with Leaflet/OpenLayers.

Click buildings to display attributes in a sidebar.

Search for buildings (ID, name, or available fields).

Form interface to input/update property tax data (tax year, assessed value, tax rate, payment status, payer name, etc.).

3. Backend API

Build a lightweight REST API (Flask, FastAPI, or Node.js/Express).

Create/update tax records in PostGIS.

Implement secure authentication for municipal staff.

4. Deployment & Documentation

Deploy complete application on Linux server or cloud VM.

Provide:

Technical documentation

Brief walkthrough

Experience Required

Applicants must have strong experience with:

Web GIS: Leaflet, OpenLayers, MapLibre

Spatial databases: PostgreSQL/PostGIS

Map servers: GeoServer (publishing layers, SLD styling)

REST API development (Flask/FastAPI or Express)

Full stack web development (JavaScript, HTML, CSS)

Authentication & basic security

Deployment on Linux servers

Bonus experience: Building tools for low-resource or Global South environments