Mike Gerwitz

Activist for User Freedom



TAME is The Algebraic Metalanguage, a programming language and system of tools designed to aid in the development, understanding, and maintenance of systems performing numerous calculations on a complex graph of dependencies, conditions, and a large number of inputs.

This system was developed at Ryan Specialty Group (formerly LoVullo Associates) to handle the complexity of comparative insurance rating systems. It is a domain-specific language (DSL) that itself encourages, through the use of templates, the creation of sub-DSLs. TAME itself is at heart a calculator—processing only numerical input and output—driven by quantifiers as predicates. Calculations and quantifiers are written declaratively without concern for order of execution.

The system has powerful dependency resolution and data flow capabilities.

TAME consists of a macro processor (implementing a metalanguage), numerous compilers for various targets (JavaScript, HTML documentation and debugging environment, LaTeX, and others), linkers, and supporting tools. The input grammar is XML, and the majority of the project (including the macro processor, compilers, and linkers) is written in XSLT. There is a reason for that odd choice; until an explanation is provided, know that someone is perverted enough to implement a full compiler in XSLT.


The current state of the project as used in production is found in src/current/. The environment surrounding the development of this project resulted in a bit of a mess, which is being refactored into src/ as it is touched. Documentation is virtually non-existent.


Compiled documentation for the latest release is available via our GitLab mirror, which uses the same build pipeline as we do on our internal GitLab instance. Available formats are:

Getting Started

To get started, make sure Saxon version 9 or later is available and its path set as SAXON_CP; that the path to hoxsl is set via HOXSL; and then run the bootstrap script:

$ export SAXON_CP=/path/to/saxon9he.jar
$ export HOXSL=/path/to/hoxsl/root

$ ./boostrap

Running Test Cases

To run the test cases, invoke make check (or its alias, make test).

Testing Core Features

In order to run tests located at core/test/core/**, a supporting environment is required. (e.g. mega rater). Inside a supporting rater, either check out a submodule containing the core tests, or temporarily add them into the submodule.

Build the core test suite summary page using:

$ make rater/core/test/core/suite.html

Visit the summary page in a web browser and click the Calculate Premium button. If all test cases pass, it will yield a value of $1.


Information for TAME developers can be found in the file HACKING.


This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.