these 5 derivations will be built:
  /nix/store/ghaqbd8vg37zwrig1w8n1il3w7qjffn3-source.drv
  /nix/store/rm1d4gnxyibkhdgvv5j8az79l3ksszbl-lean-ctx-3.12.2-vendor-staging.drv
  /nix/store/5awhr22859pdc40zcyrx0nv886q9sffw-lean-ctx-3.12.2-vendor.drv
  /nix/store/b43w53crzrm6h49fq6157hazjkrahpsx-lean-ctx-3.12.2.drv
  /nix/store/i0i6l4pq33ni7ch8pbqp0zrd7vv15j74-check-lean-ctx.drv