Some suggestions about devcontainer.json, clang-tidy, cmake-format, and ubuntu jimmy.

[nejcgalof]

Hello @lefticus. I admire your work. I have some suggestions and we can discuss about them and then I can create some PRs if they turn out to be good :

In devcontainer.json, add these settings for better automatically checking for Clang errors. VSCode shows nicely the problems and underlines the problematics line.

"C_Cpp.codeAnalysis.runAutomatically": true,  // For automatically run code analysis on save
"C_Cpp.codeAnalysis.clangTidy.enabled": true, // Clang tidy checks are included when it is run code analysis
"C_Cpp.codeAnalysis.exclude": { // Exclude checking in out directory (using presets). Maybe need some other folders too.
    "${workspaceFolder}/out/**": true

And add extension:
"cheshirekow.cmake-format" // For automatically run formating cmake files on save
This extension must have installed cmake-format. Because of this, we need to add in Dockerfile:
RUN python3 -m pip install cmake_format

In .clang-tidy I always like to add CheckOptions for example:

CheckOptions:
  - { key: readability-identifier-naming.NamespaceCase,          value: lower_case }
  - { key: readability-identifier-naming.ClassCase,              value: CamelCase  }
  - { key: readability-identifier-naming.StructCase,             value: CamelCase  }
  - { key: readability-identifier-naming.TemplateParameterCase,  value: CamelCase  }
  - { key: readability-identifier-naming.FunctionCase,           value: CamelCase  }
  - { key: readability-identifier-naming.VariableCase,           value: lower_case }
  - { key: readability-identifier-naming.PrivateMemberSuffix,    value: _          }
  - { key: readability-identifier-naming.ProtectedMemberSuffix,  value: _          }
  - { key: readability-identifier-naming.MacroDefinitionCase,    value: UPPER_CASE }
  - { key: readability-identifier-naming.EnumConstantCase,         value: CamelCase }
  - { key: readability-identifier-naming.EnumConstantPrefix,       value: k         }
  - { key: readability-identifier-naming.ConstexprVariableCase,    value: CamelCase }
  - { key: readability-identifier-naming.ConstexprVariablePrefix,  value: k         }
  - { key: readability-identifier-naming.GlobalConstantCase,       value: CamelCase }
  - { key: readability-identifier-naming.GlobalConstantPrefix,     value: k         }
  - { key: readability-identifier-naming.MemberConstantCase,       value: CamelCase }
  - { key: readability-identifier-naming.MemberConstantPrefix,     value: k         }
  - { key: readability-identifier-naming.StaticConstantCase,       value: CamelCase }
  - { key: readability-identifier-naming.StaticConstantPrefix,     value: k         }

This force developers to use the same naming conventions. What do you think?

One more suggestion is to support the new ubuntu Jimmy.