GIS Interactive Map App Development

I'm looking for a skilled developer with a solid GIS background to create a small interactive mapping application using Leaflet.js. The primary purpose of this app is to visualize demographic data.

Key Requirements:
- Use Leaflet.js for map creation
- Visualize demographic data
- Implement interactive features like:
- Zooming and panning
- Markers with pop-ups
- Drawing and measuring tools

Ideal Skills & Experience:
- Proficiency in Leaflet.js and GIS technologies
- Experience in developing interactive web maps
- Strong understanding of demographic data visualization techniques
- Familiarity with JavaScript, HTML, and CSS

Please provide samples of previous GIS and mapping projects. Looking forward to your proposals!