substituting /gnu/store/jggb1p374p6md3wkp5f46n5jx9ggs3g9-qtwebengine-5.15.2... Backtrace: In ice-9/boot-9.scm: 1752:10 19 (with-exception-handler _ _ #:unwind? _ # _) In unknown file: 18 (apply-smob/0 #<thunk 7fa05bc51f60>) In ice-9/boot-9.scm: 724:2 17 (call-with-prompt _ _ #<procedure default-prompt-handle…>) In ice-9/eval.scm: 619:8 16 (_ #(#(#<directory (guile-user) 7fa05bc4bc80>))) In guix/ui.scm: 2206:7 15 (run-guix . _) 2169:10 14 (run-guix-command _ . _) In ice-9/boot-9.scm: 1752:10 13 (with-exception-handler _ _ #:unwind? _ # _) 1752:10 12 (with-exception-handler _ _ #:unwind? _ # _) In guix/scripts/substitute.scm: 771:15 11 (_) In ice-9/exceptions.scm: 406:15 10 (process-substitution #<output: file 4> _ "/gnu/store/…" …) In ice-9/boot-9.scm: 1752:10 9 (with-exception-handler _ _ #:unwind? _ # _) In guix/scripts/substitute.scm: 479:9 8 (_) In ice-9/boot-9.scm: 1747:15 7 (with-exception-handler #<procedure 7fa05a9837b0 at ic…> …) 1685:16 6 (raise-exception _ #:continuable? _) 1683:16 5 (raise-exception _ #:continuable? _) 1685:16 4 (raise-exception _ #:continuable? _) 1780:13 3 (_ #<&compound-exception components: (#<&error> #<&irri…>) 1685:16 2 (raise-exception _ #:continuable? _) 1683:16 1 (raise-exception _ #:continuable? _) 1685:16 0 (raise-exception _ #:continuable? _) ice-9/boot-9.scm:1685:16: In procedure raise-exception: ERROR: 1. &http-get-error: uri: #<<uri> scheme: https userinfo: #f host: "ci.guix.gnu.org" port: #f path: "/nar/zstd/jggb1p374p6md3wkp5f46n5jx9ggs3g9-qtwebengine-5.15.2" query: #f fragment: #f> code: 404 reason: "Not Found" 2. &message: "https://ci.guix.gnu.org/nar/zstd/jggb1p374p6md3wkp5f46n5jx9ggs3g9-qtwebengine-5.15.2: HTTP download failed: 404 (\"Not Found\")" substitution of /gnu/store/jggb1p374p6md3wkp5f46n5jx9ggs3g9-qtwebengine-5.15.2 failed guix build: error: some substitutes for the outputs of derivation `/gnu/store/h025lkav67dg0nicgxfmwivr4vbcg2nn-qtwebengine-5.15.2.drv' failed (usually happens due to networking issues); try `--fallback' to build derivation from source