For building you only need to output this:

$ wanna-build --database=amd64/build-db --user=buildd_amd64-thrall --list=needs-build --dist=unstable-rebuild
libs/libinfinity_0.4.2-2 [optional:uncompiled:calprio{27}:days{0}]
Total 1 package(s)
$ wanna-build --database=amd64/build-db --user=buildd_amd64-thrall -v --dist=unstable-rebuild libinfinity_0.4.2-2
wanna-build Revision: db181a534e9d for sid-rebuild on amd64
- libinfinity:
   - status: ok
   - pkg-ver: libinfinity_0.4.2-2
$ wanna-build --database=amd64/build-db --user=buildd_amd64-thrall --built --dist=unstable-rebuild libinfinity_0.4.2-2