OpenAidData.org provides detailed developing aid finance data from around the world.
The app is implemented by using the Python microframework Flask. It is a lightweight app, in which all the action resides in one file: openaid.py Flask is only used for development and to render all of the website files (Frozen-Flask) completely, which can then be deployed to any web server. The interactive part then is done at the client side by Javascript thanks to the openspending project.
The CRS data can be downloaded at the OECD CRS website. The complete raw data set is a bit hidden; click on the above link in the menu on export and then on "related files". The IATI data can be downloaded at the IATI registry. The total data is way over 2GB.