Prompted by the thread "Toolset version for Visual Studio 2017 15.6.3" over in the user list, I was looking through some Boost.Build documentation when I found some dead links and other weirdness. Boost.Build's github page links to https://www.boost.org/build/, which appears to be fully working. On https://www.boost.org/doc/libs/1_66_0/more/getting_started/windows.html, under "5.2.1 Install Boost.Build" it links to https://www.boost.org/doc/libs/1_66_0/tools/build/index.html, which appears to be a versioned clone of the above. But at that page, the "Documentation" link points at https://www.boost.org/doc/libs/1_66_0/tools/build/doc/html/index.html, which 404s. Back in "Getting Started", in "5.2.2 Identify Your Toolset" it first links directly to https://www.boost.org/build/doc/html/bbv2/reference/tools.html (which is now an unversioned link, but does work), and then to https://www.boost.org/doc/libs/1_66_0/doc/html/bbv2/installation.html (which is a versioned link that also works). So it's not very consistent. Putting these things together, it looks like the "right" root page for the versioned documentation should be https://www.boost.org/doc/libs/1_66_0/doc/html/bbv2.html, although that lacks some user-friendliness. (And it also links to https://www.boost.org/boost-build2 for yet another URL variation... although that does redirect to https://www.boost.org/build/ at least.)