Open source Rails app behind iNaturalist.org
Want to help out? Fork the project and check out the Contributing Code to iNaturalist (might be a bit out of date, contact kueda if you hit problems getting set up).
Thinking about running your own version of iNaturalist? Consider joining the iNaturalist Network instead of forking the community.
Use of the Time Zone Geometries feature with the recommended source data will include information from Timezone Boundary Builder, which is made available under the Open Database License.