I have slow internet :) It looks like ftp://tug.org has a FTP session timeout of 2 hours 11 minutes, or something like that. Over night I tried to build sbcl and failed. Note how download silently stopped at ~80% [1]. Would be nice if guix had a mechanism to reconnect to FTP and continue download after timeout. Thanks! [1]: $ while :; do ./pre-inst-env guix build sbcl --no-substitutes; done @ build-started /gnu/store/ywpxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv - x86_64-linux /var/log/guix/drvs/yw//pxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv.bz2 Starting download of /gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz From ftp://tug.org/historic/systems/texlive/2016/texlive-20160523b-texmf.tar.xz... …3b-texmf.tar.xz 1.93GiB 213KiB/s 02:11:32 [################ ] 83.0% output path `/gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz' should have sha256 hash `1dv8vgfzpczqw82hv9g7a8djhhyzywljmrarlcyy6g2qi5q51glr', instead has `062qbbhlin1ys9lihax34kq503ig1fl55br84j94vwawbk04p6j0' @ build-failed /gnu/store/ywpxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv - 1 output path `/gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz' should have sha256 hash `1dv8vgfzpczqw82hv9g7a8djhhyzywljmrarlcyy6g2qi5q51glr', instead has `062qbbhlin1ys9lihax34kq503ig1fl55br84j94vwawbk04p6j0' @ build-started /gnu/store/in6vixj9fb9c8f9z3jf42zz9v40dbjxi-serf-1.3.8.drv - x86_64-linux /var/log/guix/drvs/in//6vixj9fb9c8f9z3jf42zz9v40dbjxi-serf-1.3.8.drv.bz2 cannot build derivation `/gnu/store/q9s2wdsaqvrllkcsf8w1a8424zd9ybc1-texlive-20160523b-texmf.tar.xz.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/b7abk0aarqv0ylxp2g4s2sf9j75xdy04-texlive-texmf-2016.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/kpjy0c1pl8vzxbkys6p45ij3za6a92gj-texlive-2016.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/clnamqpbkkn2k0ji1clbnznx2fyyig2c-sbcl-1.3.7.drv': 1 dependencies couldn't be built guix build: error: build failed: build of `/gnu/store/clnamqpbkkn2k0ji1clbnznx2fyyig2c-sbcl-1.3.7.drv' failed @ build-started /gnu/store/ywpxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv - x86_64-linux /var/log/guix/drvs/yw//pxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv.bz2 Starting download of /gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz From ftp://tug.org/historic/systems/texlive/2016/texlive-20160523b-texmf.tar.xz... …3b-texmf.tar.xz 1.93GiB 213KiB/s 02:11:46 [################ ] 83.3% output path `/gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz' should have sha256 hash `1dv8vgfzpczqw82hv9g7a8djhhyzywljmrarlcyy6g2qi5q51glr', instead has `1l296b4ypphffv1zpamp01g6a633kqlmfbf9l4x9411rlblb1hfd' @ build-failed /gnu/store/ywpxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv - 1 output path `/gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz' should have sha256 hash `1dv8vgfzpczqw82hv9g7a8djhhyzywljmrarlcyy6g2qi5q51glr', instead has `1l296b4ypphffv1zpamp01g6a633kqlmfbf9l4x9411rlblb1hfd' @ build-started /gnu/store/in6vixj9fb9c8f9z3jf42zz9v40dbjxi-serf-1.3.8.drv - x86_64-linux /var/log/guix/drvs/in//6vixj9fb9c8f9z3jf42zz9v40dbjxi-serf-1.3.8.drv.bz2 cannot build derivation `/gnu/store/q9s2wdsaqvrllkcsf8w1a8424zd9ybc1-texlive-20160523b-texmf.tar.xz.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/b7abk0aarqv0ylxp2g4s2sf9j75xdy04-texlive-texmf-2016.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/kpjy0c1pl8vzxbkys6p45ij3za6a92gj-texlive-2016.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/clnamqpbkkn2k0ji1clbnznx2fyyig2c-sbcl-1.3.7.drv': 1 dependencies couldn't be built guix build: error: build failed: build of `/gnu/store/clnamqpbkkn2k0ji1clbnznx2fyyig2c-sbcl-1.3.7.drv' failed @ build-started /gnu/store/ywpxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv - x86_64-linux /var/log/guix/drvs/yw//pxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv.bz2 Starting download of /gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz From ftp://tug.org/historic/systems/texlive/2016/texlive-20160523b-texmf.tar.xz... …3b-texmf.tar.xz 1.93GiB 213KiB/s 02:11:31 [################ ] 83.1% output path `/gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz' should have sha256 hash `1dv8vgfzpczqw82hv9g7a8djhhyzywljmrarlcyy6g2qi5q51glr', instead has `143zan8sh0lw2jjhdpvc7w9yjh7cw75w1ry60qq4g1n3hjmfrwi3' @ build-failed /gnu/store/ywpxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv - 1 output path `/gnu/store/xdjl5wxdjghq85nbc9qacgyzh8d54f6y-texlive-20160523b-texmf.tar.xz' should have sha256 hash `1dv8vgfzpczqw82hv9g7a8djhhyzywljmrarlcyy6g2qi5q51glr', instead has `143zan8sh0lw2jjhdpvc7w9yjh7cw75w1ry60qq4g1n3hjmfrwi3' @ build-started /gnu/store/in6vixj9fb9c8f9z3jf42zz9v40dbjxi-serf-1.3.8.drv - x86_64-linux /var/log/guix/drvs/in//6vixj9fb9c8f9z3jf42zz9v40dbjxi-serf-1.3.8.drv.bz2 cannot build derivation `/gnu/store/q9s2wdsaqvrllkcsf8w1a8424zd9ybc1-texlive-20160523b-texmf.tar.xz.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/b7abk0aarqv0ylxp2g4s2sf9j75xdy04-texlive-texmf-2016.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/kpjy0c1pl8vzxbkys6p45ij3za6a92gj-texlive-2016.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/clnamqpbkkn2k0ji1clbnznx2fyyig2c-sbcl-1.3.7.drv': 1 dependencies couldn't be built guix build: error: build failed: build of `/gnu/store/clnamqpbkkn2k0ji1clbnznx2fyyig2c-sbcl-1.3.7.drv' failed @ build-started /gnu/store/ywpxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv - x86_64-linux /var/log/guix/drvs/yw//pxpl2gp6z3sjvm7sn8gs6n4mhm2f0g-texlive-20160523b-texmf.tar.xz.drv.bz2 -- Sergei