Developer Resources

NYC Basemap & Imagery Tile Services

The GIS team has published a new OGC standard Tile Map Service (TMS) available to the public. The TMS serves multiple tiled maps (basemaps, labels, and current/historical orthoimagery) in the web mercator projection (EPSG: 3857) and is compatible with most javascript web mapping libraries such as OpenLayers, MapBox, Leaflet, and ArcGIS.
Documentation

nyc-lib

nyc-lib is a set of common libraries used to develop NYC mapping applications. The library leverages existing open mapping libraries Leaflet and OpenLayers, geoclient for geocoding, and includes accessibility features for end users using screen readers.
Documentation
Code Repository

Geoclient

The Geoclient API is a RESTful web service interface to the NYC Department of City Planning’s Geosupport system, a mainframe-based geocoding system used extensively by NYC government agencies.
Developer Portal
Code Repository