* [Ubuntu 22.04](../appendix/Install-on-Ubuntu-22.md)
* [Ubuntu 20.04](../appendix/Install-on-Ubuntu-20.md)
- * [Ubuntu 18.04](../appendix/Install-on-Ubuntu-18.md)
These OS-specific instructions can also be found in executable form
in the `vagrant/` directory.
* [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+)
* [PostgreSQL](https://www.postgresql.org) (9.6+ will work, 11+ strongly recommended)
* [PostGIS](https://postgis.net) (2.2+ will work, 3.0+ strongly recommended)
- * [Python 3](https://www.python.org/) (3.6+)
+ * [Python 3](https://www.python.org/) (3.7+)
* [Psycopg2](https://www.psycopg.org) (2.7+)
* [Python Dotenv](https://github.com/theskumar/python-dotenv)
* [psutil](https://github.com/giampaolo/psutil)
* [Jinja2](https://palletsprojects.com/p/jinja/)
+ * [SQLAlchemy](https://www.sqlalchemy.org/) (1.4.31+ with greenlet support)
+ * [asyncpg](https://magicstack.github.io/asyncpg) (0.8+)
* [PyICU](https://pypi.org/project/PyICU/)
* [PyYaml](https://pyyaml.org/) (5.1+)
* [datrie](https://github.com/pytries/datrie)
- * [PHP](https://php.net) (7.0 or later)
+ * [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:
* [pyosmium](https://osmcode.org/pyosmium/)
+For running the experimental Python frontend:
+
+ * one of the following web frameworks:
+ * [falcon](https://falconframework.org/) (3.0+)
+ * [starlette](https://www.starlette.io/)
+ * [uvicorn](https://www.uvicorn.org/)
+
For dependencies for running tests and building documentation, see
the [Development section](../develop/Development-Environment.md).