[INFO] cloning repository https://github.com/Kavelaa/kitty-blockchain [INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Kavelaa/kitty-blockchain" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain", kill_on_drop: false }` [INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain'... [INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }` [INFO] [stdout] 59627899994d3eae199052950472bbf351bd6622 [INFO] checking Kavelaa/kitty-blockchain against master#8f359beca4e58bc3ae795a666301a8f47023044c for pr-121557 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/Kavelaa/kitty-blockchain on toolchain 8f359beca4e58bc3ae795a666301a8f47023044c [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+8f359beca4e58bc3ae795a666301a8f47023044c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] finished tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] tweaked toml for git repo https://github.com/Kavelaa/kitty-blockchain written to /workspace/builds/worker-2-tc1/source/Cargo.toml [INFO] crate git repo https://github.com/Kavelaa/kitty-blockchain already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+8f359beca4e58bc3ae795a666301a8f47023044c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] error: failed to select a version for `parity-util-mem`. [INFO] [stderr] ... required by package `sp-runtime v3.0.0` [INFO] [stderr] ... which satisfies dependency `sp-runtime = "^3.0.0"` of package `pallet-balances v3.0.0` [INFO] [stderr] ... which satisfies dependency `pallet-balances = "^3.0.0"` (locked to 3.0.0) of package `pallet-kitty v3.0.0 (/workspace/builds/worker-2-tc1/source/pallets/kitty)` [INFO] [stderr] ... which satisfies path dependency `pallet-kitty` (locked to 3.0.0) of package `node-template-runtime v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc1/source/runtime)` [INFO] [stderr] ... which satisfies path dependency `node-template-runtime` (locked to 3.0.0-monthly-2021-08) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc1/source/node)` [INFO] [stderr] versions that meet the requirements `^0.9.0` are: 0.9.0 [INFO] [stderr] [INFO] [stderr] the package `parity-util-mem` links to the native library `parity-util-mem-ban-duplicates`, but it conflicts with a previous package which links to `parity-util-mem-ban-duplicates` as well: [INFO] [stderr] package `parity-util-mem v0.10.0` [INFO] [stderr] ... which satisfies dependency `parity-util-mem = "^0.10.0"` (locked to 0.10.0) of package `sc-service v0.10.0-dev (https://github.com/paritytech/substrate.git?tag=monthly-2021-08#4d28ebeb)` [INFO] [stderr] ... which satisfies git dependency `sc-service` (locked to 0.10.0-dev) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc1/source/node)` [INFO] [stderr] Only one package in the dependency graph may specify the same links value. This helps ensure that only one copy of a native library is linked in the final binary. Try to adjust your dependencies so that only one package uses the `links = "parity-util-mem-ban-duplicates"` value. For more information, see https://doc.rust-lang.org/cargo/reference/resolver.html#links. [INFO] [stderr] [INFO] [stderr] failed to select a version for `parity-util-mem` which could resolve this conflict [ERROR] this task or one of its parent failed! [ERROR] command failed: exit status: 101 [ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace. [INFO] checking Kavelaa/kitty-blockchain against try#80d5fe37e16a0befb4128414cb6a11d544788c0a for pr-121557 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/Kavelaa/kitty-blockchain on toolchain 80d5fe37e16a0befb4128414cb6a11d544788c0a [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] finished tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] tweaked toml for git repo https://github.com/Kavelaa/kitty-blockchain written to /workspace/builds/worker-2-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/Kavelaa/kitty-blockchain already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] error: failed to select a version for `parity-util-mem`. [INFO] [stderr] ... required by package `sp-runtime v3.0.0` [INFO] [stderr] ... which satisfies dependency `sp-runtime = "^3.0.0"` of package `pallet-balances v3.0.0` [INFO] [stderr] ... which satisfies dependency `pallet-balances = "^3.0.0"` (locked to 3.0.0) of package `pallet-kitty v3.0.0 (/workspace/builds/worker-2-tc2/source/pallets/kitty)` [INFO] [stderr] ... which satisfies path dependency `pallet-kitty` (locked to 3.0.0) of package `node-template-runtime v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/runtime)` [INFO] [stderr] ... which satisfies path dependency `node-template-runtime` (locked to 3.0.0-monthly-2021-08) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] versions that meet the requirements `^0.9.0` are: 0.9.0 [INFO] [stderr] [INFO] [stderr] the package `parity-util-mem` links to the native library `parity-util-mem-ban-duplicates`, but it conflicts with a previous package which links to `parity-util-mem-ban-duplicates` as well: [INFO] [stderr] package `parity-util-mem v0.10.0` [INFO] [stderr] ... which satisfies dependency `parity-util-mem = "^0.10.0"` (locked to 0.10.0) of package `sc-service v0.10.0-dev (https://github.com/paritytech/substrate.git?tag=monthly-2021-08#4d28ebeb)` [INFO] [stderr] ... which satisfies git dependency `sc-service` (locked to 0.10.0-dev) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] Only one package in the dependency graph may specify the same links value. This helps ensure that only one copy of a native library is linked in the final binary. Try to adjust your dependencies so that only one package uses the `links = "parity-util-mem-ban-duplicates"` value. For more information, see https://doc.rust-lang.org/cargo/reference/resolver.html#links. [INFO] [stderr] [INFO] [stderr] failed to select a version for `parity-util-mem` which could resolve this conflict [INFO] checking Kavelaa/kitty-blockchain against try#80d5fe37e16a0befb4128414cb6a11d544788c0a for pr-121557 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/Kavelaa/kitty-blockchain on toolchain 80d5fe37e16a0befb4128414cb6a11d544788c0a [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] finished tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] tweaked toml for git repo https://github.com/Kavelaa/kitty-blockchain written to /workspace/builds/worker-2-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/Kavelaa/kitty-blockchain already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] error: failed to select a version for `parity-util-mem`. [INFO] [stderr] ... required by package `sp-runtime v3.0.0` [INFO] [stderr] ... which satisfies dependency `sp-runtime = "^3.0.0"` of package `pallet-balances v3.0.0` [INFO] [stderr] ... which satisfies dependency `pallet-balances = "^3.0.0"` (locked to 3.0.0) of package `pallet-kitty v3.0.0 (/workspace/builds/worker-2-tc2/source/pallets/kitty)` [INFO] [stderr] ... which satisfies path dependency `pallet-kitty` (locked to 3.0.0) of package `node-template-runtime v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/runtime)` [INFO] [stderr] ... which satisfies path dependency `node-template-runtime` (locked to 3.0.0-monthly-2021-08) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] versions that meet the requirements `^0.9.0` are: 0.9.0 [INFO] [stderr] [INFO] [stderr] the package `parity-util-mem` links to the native library `parity-util-mem-ban-duplicates`, but it conflicts with a previous package which links to `parity-util-mem-ban-duplicates` as well: [INFO] [stderr] package `parity-util-mem v0.10.0` [INFO] [stderr] ... which satisfies dependency `parity-util-mem = "^0.10.0"` (locked to 0.10.0) of package `sc-service v0.10.0-dev (https://github.com/paritytech/substrate.git?tag=monthly-2021-08#4d28ebeb)` [INFO] [stderr] ... which satisfies git dependency `sc-service` (locked to 0.10.0-dev) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] Only one package in the dependency graph may specify the same links value. This helps ensure that only one copy of a native library is linked in the final binary. Try to adjust your dependencies so that only one package uses the `links = "parity-util-mem-ban-duplicates"` value. For more information, see https://doc.rust-lang.org/cargo/reference/resolver.html#links. [INFO] [stderr] [INFO] [stderr] failed to select a version for `parity-util-mem` which could resolve this conflict [INFO] checking Kavelaa/kitty-blockchain against try#80d5fe37e16a0befb4128414cb6a11d544788c0a for pr-121557 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/Kavelaa/kitty-blockchain on toolchain 80d5fe37e16a0befb4128414cb6a11d544788c0a [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] finished tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] tweaked toml for git repo https://github.com/Kavelaa/kitty-blockchain written to /workspace/builds/worker-2-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/Kavelaa/kitty-blockchain already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] error: failed to select a version for `parity-util-mem`. [INFO] [stderr] ... required by package `sp-runtime v3.0.0` [INFO] [stderr] ... which satisfies dependency `sp-runtime = "^3.0.0"` of package `pallet-balances v3.0.0` [INFO] [stderr] ... which satisfies dependency `pallet-balances = "^3.0.0"` (locked to 3.0.0) of package `pallet-kitty v3.0.0 (/workspace/builds/worker-2-tc2/source/pallets/kitty)` [INFO] [stderr] ... which satisfies path dependency `pallet-kitty` (locked to 3.0.0) of package `node-template-runtime v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/runtime)` [INFO] [stderr] ... which satisfies path dependency `node-template-runtime` (locked to 3.0.0-monthly-2021-08) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] versions that meet the requirements `^0.9.0` are: 0.9.0 [INFO] [stderr] [INFO] [stderr] the package `parity-util-mem` links to the native library `parity-util-mem-ban-duplicates`, but it conflicts with a previous package which links to `parity-util-mem-ban-duplicates` as well: [INFO] [stderr] package `parity-util-mem v0.10.0` [INFO] [stderr] ... which satisfies dependency `parity-util-mem = "^0.10.0"` (locked to 0.10.0) of package `sc-service v0.10.0-dev (https://github.com/paritytech/substrate.git?tag=monthly-2021-08#4d28ebeb)` [INFO] [stderr] ... which satisfies git dependency `sc-service` (locked to 0.10.0-dev) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] Only one package in the dependency graph may specify the same links value. This helps ensure that only one copy of a native library is linked in the final binary. Try to adjust your dependencies so that only one package uses the `links = "parity-util-mem-ban-duplicates"` value. For more information, see https://doc.rust-lang.org/cargo/reference/resolver.html#links. [INFO] [stderr] [INFO] [stderr] failed to select a version for `parity-util-mem` which could resolve this conflict [INFO] checking Kavelaa/kitty-blockchain against try#80d5fe37e16a0befb4128414cb6a11d544788c0a for pr-121557 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/Kavelaa/kitty-blockchain on toolchain 80d5fe37e16a0befb4128414cb6a11d544788c0a [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] finished tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] tweaked toml for git repo https://github.com/Kavelaa/kitty-blockchain written to /workspace/builds/worker-2-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/Kavelaa/kitty-blockchain already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] error: failed to select a version for `parity-util-mem`. [INFO] [stderr] ... required by package `sp-runtime v3.0.0` [INFO] [stderr] ... which satisfies dependency `sp-runtime = "^3.0.0"` of package `pallet-balances v3.0.0` [INFO] [stderr] ... which satisfies dependency `pallet-balances = "^3.0.0"` (locked to 3.0.0) of package `pallet-kitty v3.0.0 (/workspace/builds/worker-2-tc2/source/pallets/kitty)` [INFO] [stderr] ... which satisfies path dependency `pallet-kitty` (locked to 3.0.0) of package `node-template-runtime v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/runtime)` [INFO] [stderr] ... which satisfies path dependency `node-template-runtime` (locked to 3.0.0-monthly-2021-08) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] versions that meet the requirements `^0.9.0` are: 0.9.0 [INFO] [stderr] [INFO] [stderr] the package `parity-util-mem` links to the native library `parity-util-mem-ban-duplicates`, but it conflicts with a previous package which links to `parity-util-mem-ban-duplicates` as well: [INFO] [stderr] package `parity-util-mem v0.10.0` [INFO] [stderr] ... which satisfies dependency `parity-util-mem = "^0.10.0"` (locked to 0.10.0) of package `sc-service v0.10.0-dev (https://github.com/paritytech/substrate.git?tag=monthly-2021-08#4d28ebeb)` [INFO] [stderr] ... which satisfies git dependency `sc-service` (locked to 0.10.0-dev) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] Only one package in the dependency graph may specify the same links value. This helps ensure that only one copy of a native library is linked in the final binary. Try to adjust your dependencies so that only one package uses the `links = "parity-util-mem-ban-duplicates"` value. For more information, see https://doc.rust-lang.org/cargo/reference/resolver.html#links. [INFO] [stderr] [INFO] [stderr] failed to select a version for `parity-util-mem` which could resolve this conflict [INFO] checking Kavelaa/kitty-blockchain against try#80d5fe37e16a0befb4128414cb6a11d544788c0a for pr-121557 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKavelaa%2Fkitty-blockchain" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/Kavelaa/kitty-blockchain on toolchain 80d5fe37e16a0befb4128414cb6a11d544788c0a [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] finished tweaking git repo https://github.com/Kavelaa/kitty-blockchain [INFO] tweaked toml for git repo https://github.com/Kavelaa/kitty-blockchain written to /workspace/builds/worker-2-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/Kavelaa/kitty-blockchain already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+80d5fe37e16a0befb4128414cb6a11d544788c0a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] error: failed to select a version for `parity-util-mem`. [INFO] [stderr] ... required by package `sp-runtime v3.0.0` [INFO] [stderr] ... which satisfies dependency `sp-runtime = "^3.0.0"` of package `pallet-balances v3.0.0` [INFO] [stderr] ... which satisfies dependency `pallet-balances = "^3.0.0"` (locked to 3.0.0) of package `pallet-kitty v3.0.0 (/workspace/builds/worker-2-tc2/source/pallets/kitty)` [INFO] [stderr] ... which satisfies path dependency `pallet-kitty` (locked to 3.0.0) of package `node-template-runtime v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/runtime)` [INFO] [stderr] ... which satisfies path dependency `node-template-runtime` (locked to 3.0.0-monthly-2021-08) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] versions that meet the requirements `^0.9.0` are: 0.9.0 [INFO] [stderr] [INFO] [stderr] the package `parity-util-mem` links to the native library `parity-util-mem-ban-duplicates`, but it conflicts with a previous package which links to `parity-util-mem-ban-duplicates` as well: [INFO] [stderr] package `parity-util-mem v0.10.0` [INFO] [stderr] ... which satisfies dependency `parity-util-mem = "^0.10.0"` (locked to 0.10.0) of package `sc-service v0.10.0-dev (https://github.com/paritytech/substrate.git?tag=monthly-2021-08#4d28ebeb)` [INFO] [stderr] ... which satisfies git dependency `sc-service` (locked to 0.10.0-dev) of package `node-template v3.0.0-monthly-2021-08 (/workspace/builds/worker-2-tc2/source/node)` [INFO] [stderr] Only one package in the dependency graph may specify the same links value. This helps ensure that only one copy of a native library is linked in the final binary. Try to adjust your dependencies so that only one package uses the `links = "parity-util-mem-ban-duplicates"` value. For more information, see https://doc.rust-lang.org/cargo/reference/resolver.html#links. [INFO] [stderr] [INFO] [stderr] failed to select a version for `parity-util-mem` which could resolve this conflict [ERROR] this task or one of its parent failed! [ERROR] command failed: exit status: 101 [ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.