* [bzip2](http://www.bzip.org/)
* [zlib](https://www.zlib.net/)
* [ICU](http://site.icu-project.org/)
+ * [nlohmann/json](https://json.nlohmann.me/)
* [Boost libraries](https://www.boost.org/), including system and filesystem
* PostgreSQL client libraries
* a recent C++ compiler (gcc 5+ or Clang 3.8+)
* [PHP](https://php.net) (7.3+)
* PHP-pgsql
* PHP-intl (bundled with PHP)
- * PHP-cgi (for running queries from the command line)
For running continuous updates: