040000 tree 557ce06822d0097b8653cd1400296929af200660	cli
040000 tree 270a2e2fa1e4f2d65785fa8cca0b38735bd111b7	internals
040000 tree 8188a00900a804fd51a5a96e0a5366c4f5acaef0	intro
040000 tree ed75b94ebde0c795168dff9f717c8f6d371da2b9	language