A dictionary mapping the names of the builders available through this environment to underlying Builder objects. Builders named Alias, CFile, CXXFile, DVI, Library, Object, PDF, PostScript, and Program are available by default. If you initialize this variable when an Environment is created: env = Environment(BUILDERS = {'NewBuilder' : foo}) the default Builders will no longer be available. To use a new Builder object in addition to the default Builders, add your new Builder object like this: env = Environment() env.Append(BUILDERS = {'NewBuilder' : foo}) or this: env = Environment() env['BUILDERS]['NewBuilder'] = foo A function that converts a string into a Dir instance relative to the target being built. A dictionary of environment variables to use when invoking commands. When &cv-ENV; is used in a command all list values will be joined using the path separator and any other non-string values will simply be coerced to a string. Note that, by default, &scons; does not propagate the environment in force when you execute &scons; to the commands used to build target files. This is so that builds will be guaranteed repeatable regardless of the environment variables set at the time &scons; is invoked. If you want to propagate your environment variables to the commands executed to build target files, you must do so explicitly: import os env = Environment(ENV = os.environ) Note that you can choose only to propagate certain environment variables. A common example is the system PATH environment variable, so that &scons; uses the same utilities as the invoking shell (or other process): import os env = Environment(ENV = {'PATH' : os.environ['PATH']}) A function that converts a string into a File instance relative to the target being built. A list of the available implicit dependency scanners. New file scanners may be added by appending to this list, although the more flexible approach is to associate scanners with a specific Builder. See the sections "Builder Objects" and "Scanner Objects," below, for more information. A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A reserved variable name that may not be set or used in a construction environment. (See "Variable Substitution," below.) A list of the names of the Tool specifications that are part of this construction environment.