Hello, Guix Help! I watch an issue. Trying to roll-back and choose another kernel in grub I have no changes. Guix says 'Wrong type to upply: #t' # guix pull  --substitute-urls=https://berlin.guixsd.org Updating channel 'guix' from Git repository at 'https://git.savannah.gnu.org/git/guix.git' ... Building from this channel:   guix      https://git.savannah.gnu.org/git/guix.git     cddc030 Computing Guix derivation for 'x86_64-linux'... - The following derivations will be built:    /gnu/store/swnx6wdgb7b46m450rqsagczss8v09qk-profile.drv    /gnu/store/y02zb0irq8d0zicsh7cfirp0ax7r2mv5-ca-certificate-bundle.drv    /gnu/store/pqxzpznd11wgbszk2g93rb2ymisasrhy-fonts-dir.drv    /gnu/store/nlzn5h8r8n6w0ga5mxxd6dkkvv2isfgr-info-dir.drv    /gnu/store/xw73gmjq3idgd4bkbkkc7lnxp237px8b-config.scm.drv    /gnu/store/683h596w7m0zxgz9kc3ivhwaqnfrzdka-guix-config-source.drv    /gnu/store/6jyhgb0fpv3w86vqj40q23smhng4jvsq-guix-cli.drv    /gnu/store/6wqfy3l4i2slh213ifnh6djdvxz06ima-guix-packages-base.drv    /gnu/store/94k6sl6vrd9zaryz2hnm9r6y721rrla6-guix-system.drv    /gnu/store/c86n77i6zf9kn4rn20bkq5935xpkd1zh-guix-config.drv    /gnu/store/gkbgcbg379fpcwdhlipqyn4gw6xp7ggx-guix-packages.drv    /gnu/store/2z00yh2lz84fki8fyqx6jc68lf38h134-guix-command.drv    /gnu/store/ibsy655dw4rvnp16vphapj2qk5qj7nb9-guix-cddc0300b-modules.drv    /gnu/store/wn3wjpyn7wm1z7zz6s1sqrf222qi9b4x-guix-cddc0300b-modules.drv    /gnu/store/5jhhh418mlaxmqpmb956xldbrmh4mmrd-manual-database.drv    /gnu/store/js1ghld6vqfwnd3iswvkw825ywnnjgsc-guix-cddc0300b.drv substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% substitute: updating substitutes from 'https://berlin.guixsd.org '... 100.0% building /gnu/store/6wqfy3l4i2slh213ifnh6djdvxz06ima-guix-packages-base.drv... compiling...    100.0% of 235 files successfully built /gnu/store/6wqfy3l4i2slh213ifnh6djdvxz06ima-guix-packages-base.drv building /gnu/store/xw73gmjq3idgd4bkbkkc7lnxp237px8b-config.scm.drv... successfully built /gnu/store/xw73gmjq3idgd4bkbkkc7lnxp237px8b-config.scm.drv building /gnu/store/gkbgcbg379fpcwdhlipqyn4gw6xp7ggx-guix-packages.drv... compiling...    100.0% of 180 files successfully built /gnu/store/gkbgcbg379fpcwdhlipqyn4gw6xp7ggx-guix-packages.drv building /gnu/store/683h596w7m0zxgz9kc3ivhwaqnfrzdka-guix-config-source.drv... successfully built /gnu/store/683h596w7m0zxgz9kc3ivhwaqnfrzdka-guix-config-source.drv building /gnu/store/94k6sl6vrd9zaryz2hnm9r6y721rrla6-guix-system.drv... compiling...    100.0% of 68 files successfully built /gnu/store/94k6sl6vrd9zaryz2hnm9r6y721rrla6-guix-system.drv building /gnu/store/wn3wjpyn7wm1z7zz6s1sqrf222qi9b4x-guix-cddc0300b-modules.drv... successfully built /gnu/store/wn3wjpyn7wm1z7zz6s1sqrf222qi9b4x-guix-cddc0300b-modules.drv building /gnu/store/6jyhgb0fpv3w86vqj40q23smhng4jvsq-guix-cli.drv... compiling...    100.0% of 41 files successfully built /gnu/store/6jyhgb0fpv3w86vqj40q23smhng4jvsq-guix-cli.drv building /gnu/store/c86n77i6zf9kn4rn20bkq5935xpkd1zh-guix-config.drv... compiling...    100.0% of 1 files successfully built /gnu/store/c86n77i6zf9kn4rn20bkq5935xpkd1zh-guix-config.drv building /gnu/store/ibsy655dw4rvnp16vphapj2qk5qj7nb9-guix-cddc0300b-modules.drv... successfully built /gnu/store/ibsy655dw4rvnp16vphapj2qk5qj7nb9-guix-cddc0300b-modules.drv building /gnu/store/2z00yh2lz84fki8fyqx6jc68lf38h134-guix-command.drv... successfully built /gnu/store/2z00yh2lz84fki8fyqx6jc68lf38h134-guix-command.drv building /gnu/store/js1ghld6vqfwnd3iswvkw825ywnnjgsc-guix-cddc0300b.drv... successfully built /gnu/store/js1ghld6vqfwnd3iswvkw825ywnnjgsc-guix-cddc0300b.drv building /gnu/store/y02zb0irq8d0zicsh7cfirp0ax7r2mv5-ca-certificate-bundle.drv... successfully built /gnu/store/y02zb0irq8d0zicsh7cfirp0ax7r2mv5-ca-certificate-bundle.drv building /gnu/store/pqxzpznd11wgbszk2g93rb2ymisasrhy-fonts-dir.drv... successfully built /gnu/store/pqxzpznd11wgbszk2g93rb2ymisasrhy-fonts-dir.drv building /gnu/store/nlzn5h8r8n6w0ga5mxxd6dkkvv2isfgr-info-dir.drv... successfully built /gnu/store/nlzn5h8r8n6w0ga5mxxd6dkkvv2isfgr-info-dir.drv building /gnu/store/5jhhh418mlaxmqpmb956xldbrmh4mmrd-manual-database.drv... Creating manual page database... 0 entries processed in 0.0 s successfully built /gnu/store/5jhhh418mlaxmqpmb956xldbrmh4mmrd-manual-database.drv building /gnu/store/swnx6wdgb7b46m450rqsagczss8v09qk-profile.drv... successfully built /gnu/store/swnx6wdgb7b46m450rqsagczss8v09qk-profile.drv 1 package in profile New in this revision:   1 new package: r-weights Backtrace:            9 (primitive-load "/root/.config/guix/current/bin/guix") In guix/ui.scm:   1583:12  8 (run-guix-command _ . _) In ice-9/boot-9.scm:     829:9  7 (catch _ _ # …)     829:9  6 (catch _ _ # …)     829:9  5 (catch _ _ # …) In guix/scripts/pull.scm:    507:16  4 (_) In guix/status.scm:     600:4  3 (call-with-status-report _ _) In guix/scripts/pull.scm:    535:24  2 (_) In guix/store.scm:   1605:24  1 (run-with-store _ _ #:guile-for-build _ #:system _ # _) In unknown file:            0 (_ #) ERROR: Wrong type to apply: #t # guix describe Generation 25    Nov 06 2018 18:42:03    (current)   guix cddc030     repository URL: https://git.savannah.gnu.org/git/guix.git     branch: master     commit: cddc0300b7fb5fbbc80f45a626073f8372bf491f # guix system list-generations Generation 1    Sep 17 2018 18:23:13   file name: /var/guix/profiles/system-1-link   canonical file name: /gnu/store/xzsghmp223qr5j6z5h01g4c91lh04mv8-system   label: GNU with Linux-Libre 4.17.3 (beta)   bootloader: grub   root device: /dev/sda1   kernel: /gnu/store/s34syxcgp84siz2f77f0qakhgqm928h8-linux-libre-4.17.3/bzImage Generation 2    Sep 18 2018 19:39:13   file name: /var/guix/profiles/system-2-link   canonical file name: /gnu/store/0y46rxp6qz257zskarfpkbfk4l5v30sg-system   label: GNU with Linux-Libre 4.17.3 (beta)   bootloader: grub   root device: /dev/sda1   kernel: /gnu/store/s34syxcgp84siz2f77f0qakhgqm928h8-linux-libre-4.17.3/bzImage Generation 3    Sep 19 2018 21:39:30   file name: /var/guix/profiles/system-3-link   canonical file name: /gnu/store/kccf2ka5bjc9vaxj05dzij49bpyz220b-system   label: GNU with Linux-Libre 4.17.2 (beta)   bootloader: grub   root device: /dev/sda1   kernel: /gnu/store/frazbakhb56878ln4j0fr77z5h8836vi-linux-libre-4.17.2/bzImage Generation 4    Sep 20 2018 11:14:22    (current)   file name: /var/guix/profiles/system-4-link   canonical file name: /gnu/store/b7d7vl32a3m0f5zjcr1f0ljha72w9pf4-system   label: GNU with Linux-Libre 4.17 (beta)   bootloader: grub   root device: /dev/sda1   kernel: /gnu/store/khxmq6p1470171537z8agikiqmi469jr-linux-libre-4.17/bzImage Generation 5    Oct 14 2018 17:48:59   file name: /var/guix/profiles/system-5-link   canonical file name: /gnu/store/1kwx2a8gz3qgbdf8gm1frd13g7l5my26-system   label: GNU with Linux-Libre 4.18.11 (beta)   bootloader: grub   root device: /dev/sda1   kernel: /gnu/store/01l871gr200yfilx4rg6xx3wg54cpa57-linux-libre-4.18.11/bzImage Generation 6    Oct 20 2018 14:47:06   file name: /var/guix/profiles/system-6-link   canonical file name: /gnu/store/zgc200lxj4bgdawvgcffznf545vv02zz-system   label: GNU with Linux-Libre 4.18.15 (beta)   bootloader: grub   root device: /dev/sda1   kernel: /gnu/store/hh1dcny44id74ph3v3bmpwyzpss1w95s-linux-libre-4.18.15/bzImage May be I need to choose right generation? What to do?