• subst
• Refactor node hierarchy
• IAPAT framework
• IAPAT initialization
• Cross-compile
• IAPAT-based configure
• Command-line options
• Command-line variables
• Probes of platform information
• Create header files
• Toolchain
• Convert (P)SPAWN to subprocess
• Taskmaster next generation
• componentization model / Parts integration
• tests as dirs + expose test strings + unittest
• take many tools out of scons core, make them plug-ins
• refactor Help()