building python2-cryptography fails its testsuite

[ng0]

When I'm building python2-cryptography on limited resources (~512MB RAM,
1 virt. CPU), it fails its check phase after 2893.9 seconds. Is this
resources related or currently a package issue?

tests/hazmat/primitives/test_keywrap.py .........phase `check' failed
after 2893.9 seconds
builder for
`/gnu/store/ya8x3nykgk0h2kj50ak02xmx115z703q-python2-cryptography-1.7.1.drv'
failed with exit code 1
cannot build derivation
`/gnu/store/qkkrjk9pyc19jsasx1rmspvskm8wq3qk-certbot-0.12.0.drv': 1
dependencies couldn't be built
cannot build derivation
`/gnu/store/j7qi8wy1gv400f84m3j9zmq7gj9m51aa-python2-acme-0.12.0.drv': 1
dependencies couldn't be built
cannot build derivation
`/gnu/store/b60g4as3hr4fhc4mf93b1g1db56fxrvp-python2-cryptography-1.7.1.drv':
1 dependencies couldn't be built
cannot build derivation
`/gnu/store/24j6cpjcyz922amygp9jlrf5wr74nj27-python2-ndg-httpsclient-0.4.2.drv':
1 dependencies couldn't be built
cannot build derivation
`/gnu/store/6804qgshi4wcp4dbpg2bbrsndr1kgbvx-profile.drv': 1
dependencies couldn't be built
guix package: error: build failed: build of
`/gnu/store/6804qgshi4wcp4dbpg2bbrsndr1kgbvx-profile.drv' failed