Unit testing asserts can be difficult to use. Approval tests simplify this by taking a snapshot of the results, and confirming that they have not changed.

AppScale is a platform that allows users to deploy and host their own Google App Engine applications. It executes automatically over Amazon EC2, Google Compute Engine, Rackspace, Eucalyptus, CloudStack, OpenStack, as well as Xen, VirtualBox, VMWare, and KVM. It has been developed and is maintained by AppScale Systems, Inc., in Santa Barbara, CA. It supports the Python, Java, PHP, and Go Google App Engine platforms.

Appsta is designed to make bootstrapping new Rails applications much easier. It provides a helper library for writing Rails templates, to quickly setup your projects on Heroku, GitHub, and other things to get your app up and running quickly.

an Automated Pythonic Code Tester. This package is designed to run tests on a code repository on a daily basis. It comes with a set of predefined test, essentially for python packages, and a set of predefined reports to display execution results. However, it has been designed to be highly extensible, so you could write your own test or report using the Python language.

Aqua is a new Ruby library that aims to painlessly persists objects, allowing developers to focus more on object oriented code and less on storage.

An open-source database with a flexible data model for documents, graphs, and key-values. Build high performance applications using a convenient sql-like query language or JavaScript/Ruby extensions.

Arbiter is a requirements gathering and acceptance testing tool for project managers and web developers, to help ease client interaction. The project specification can be defined in word processor format as you would normally. By adding some special items, such as titled bulleted lists and highlighted text items, both a test suite and glossary can be written right into the spec. The Arbiter server will parse these documents and run the tests, reporting the results into the documents themselves. This allows the client to see project process.

It also allows the developers, sitting next to the client, to add concrete executable examples of the use cases. This adds clarity and helps to settle disputes over required functionality. Using the glossary, developers can signal to the client that concepts are not well understood. Tests can be marked pending if a document contains unexplained glossary items.

Archetype is designed to fill the gap that other frameworks and libraries leaves in the (script removed) Structure and ease of development.

Archi is a free, open source, cross-platform tool to create ArchiMate models. ArchiMate1 is an open and independent Enterprise Architecture modelling language that supports the description, analysis and visualization of architecture within and across business domains.

ArchStudio is an open-source software and systems architecture development environment developed by the Institute for Software Research at the University of California, Irvine. It is an environment of integrated tools for modeling, visualizing, analyzing and implementing software and systems architectures. It is based on the Eclipse open development platform. It is released under a BSD-style license.