diff --git a/Justfile b/Justfile
index d6adb91..146305c 100644
--- a/Justfile
+++ b/Justfile
@@ -19,14 +19,23 @@ udeps:
 
 # Run all tests with nextest and cargo-llvm-cov
 ci-test:
-	#!/bin/bash -eux
-	source <(cargo llvm-cov show-env --export-prefix)
-	cargo llvm-cov clean --workspace
-
-	export RUST_LOG=trace
-	cargo nextest run --release --all-features --profile ci
-	export ONE_BYTE_READ=1
-	cargo nextest run --release --all-features --profile ci
-
-	cargo llvm-cov report --release --ignore-filename-regex 'corpus/mod\.rs$' --lcov --output-path coverage.lcov
-	cargo llvm-cov report --release --ignore-filename-regex 'corpus/mod\.rs$' --html
+    #!/bin/bash -eux
+    export RUSTUP_TOOLCHAIN=nightly
+    rustup component add llvm-tools
+    cargo llvm-cov --version
+
+    cargo llvm-cov show-env --branch --export-prefix > /tmp/llvm-cov-env
+    echo "======= LLVM cov env ======="
+    cat /tmp/llvm-cov-env
+    echo "============================"
+    source /tmp/llvm-cov-env
+
+    cargo llvm-cov clean --workspace
+
+    export RUST_LOG=trace
+    cargo nextest run --release --all-features --profile ci
+    export ONE_BYTE_READ=1
+    cargo nextest run --release --all-features --profile ci
+
+    cargo llvm-cov report --release --ignore-filename-regex 'corpus/mod\.rs$' --lcov --output-path coverage.lcov
+    cargo llvm-cov report --release --ignore-filename-regex 'corpus/mod\.rs$' --html
diff --git a/flake.lock b/flake.lock
index 03b90d1..e14a488 100644
--- a/flake.lock
+++ b/flake.lock
@@ -7,11 +7,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1707461758,
-        "narHash": "sha256-VaqINICYEtVKF0X+chdNtXcNp6poZr385v6AG7j0ybM=",
+        "lastModified": 1710886643,
+        "narHash": "sha256-saTZuv9YeZ9COHPuj8oedGdUwJZcbQ3vyRqe7NVJMsQ=",
         "owner": "ipetkov",
         "repo": "crane",
-        "rev": "505976eaeac289fe41d074bee37006ac094636bb",
+        "rev": "5bace74e9a65165c918205cf67ad3977fe79c584",
         "type": "github"
       },
       "original": {
@@ -25,11 +25,11 @@
         "systems": "systems"
       },
       "locked": {
-        "lastModified": 1705309234,
-        "narHash": "sha256-uNRRNRKmJyCRC/8y1RqBkqWBLM034y4qN7EprSdmgyA=",
+        "lastModified": 1710146030,
+        "narHash": "sha256-SZ5L6eA7HJ/nmkzGG7/ISclqe6oZdOZTNoesiInkXPQ=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "1ef2e671c3b0c19053962c07dbda38332dcebf26",
+        "rev": "b1d9ab70662946ef0850d488da1c9019f3a9752a",
         "type": "github"
       },
       "original": {
@@ -40,11 +40,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1707268954,
-        "narHash": "sha256-2en1kvde3cJVc3ZnTy8QeD2oKcseLFjYPLKhIGDanQ0=",
+        "lastModified": 1711001935,
+        "narHash": "sha256-URtGpHue7HHZK0mrHnSf8wJ6OmMKYSsoLmJybrOLFSQ=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "f8e2ebd66d097614d51a56a755450d4ae1632df1",
+        "rev": "20f77aa09916374aa3141cbc605c955626762c9a",
         "type": "github"
       },
       "original": {
@@ -72,11 +72,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1707444620,
-        "narHash": "sha256-P8kRkiJLFttN+hbAOlm11wPxUrQZqKle+QtVCqFiGXY=",
+        "lastModified": 1711073443,
+        "narHash": "sha256-PpNb4xq7U5Q/DdX40qe7CijUsqhVVM3VZrhN0+c6Lcw=",
         "owner": "oxalica",
         "repo": "rust-overlay",
-        "rev": "78503e9199010a4df714f29a4f9c00eb2ccae071",
+        "rev": "eec55ba9fcde6be4c63942827247e42afef7fafe",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index be8ef3e..e65ff52 100644
--- a/flake.nix
+++ b/flake.nix
@@ -50,10 +50,6 @@
         version = "latest";
         strictDeps = true;
         dontStrip = true;
-        # workaround for https://github.com/NixOS/nixpkgs/issues/166205
-        env = with pkgs; lib.optionalAttrs stdenv.cc.isClang {
-          NIX_LDFLAGS = "-l${stdenv.cc.libcxx.cxxabi.libName}";
-        };
         inherit src buildInputs nativeBuildInputs;
       };
       cargoArtifacts = craneLib.buildDepsOnly commonArgs;
@@ -68,8 +64,7 @@
         default = bin;
       };
       devShells.default = mkShell {
-        inputsFrom = [ bin ];
-        packages = with pkgs; [ just nixpkgs-fmt ];
+        packages = with pkgs; [ just nixpkgs-fmt mold libiconv ];
       };
     }
     );
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index d24f9dc..525d356 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,3 +1,3 @@
 [toolchain]
-channel = "stable"
+channel = "1.77.0"
 components = ["llvm-tools", "clippy", "rust-src"]