diff --git a/.editorconfig b/.editorconfig
index a5bf0354..98ad74b1 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -11,5 +11,5 @@ indent_size = 4
 trim_trailing_whitespace = true
 max_line_length = 80
 
-[{*.nix,*.yml}]
+[{*.md,*.nix,*.toml,*.yml}]
 indent_size = 2
diff --git a/.envrc b/.envrc
index 1d953f4b..3550a30f 100644
--- a/.envrc
+++ b/.envrc
@@ -1 +1 @@
-use nix
+use flake
diff --git a/.github/workflows/_build-rust.yml b/.github/workflows/_build-rust.yml
index 2d617544..47a5ed79 100644
--- a/.github/workflows/_build-rust.yml
+++ b/.github/workflows/_build-rust.yml
@@ -102,8 +102,7 @@ jobs:
         run: |
           rustup component add miri
           # Run with stack-borrow model
-          # XXX Temporarily, just for multiboot2 crate.
-          cargo miri test -p multiboot2
+          cargo miri test
           # Run with tree-borrow model
-          # XXX Temporarily, just for multiboot2 crate.
-          MIRIFLAGS=-Zmiri-tree-borrows cargo +nightly miri test -p multiboot2
+          # TODO currently doesn't work with the ELF section parsing code
+          # MIRIFLAGS="-Zmiri-tree-borrows" cargo +nightly miri test
diff --git a/.github/workflows/integrationtest.yml b/.github/workflows/integrationtest.yml
index d9621181..420f3e33 100644
--- a/.github/workflows/integrationtest.yml
+++ b/.github/workflows/integrationtest.yml
@@ -26,13 +26,7 @@ jobs:
     steps:
       - name: Check out
         uses: actions/checkout@v4
-      - uses: cachix/install-nix-action@v30
-        with:
-          # This channel is only required to invoke "nix-shell".
-          # Everything inside that nix-shell will use a pinned version of
-          # nixpkgs.
-          nix_path: nixpkgs=channel:nixos-23.11
-      - uses: DeterminateSystems/magic-nix-cache-action@main
+      - uses: cachix/install-nix-action@v31
       - name: Set up cargo cache
         uses: actions/cache@v4
         continue-on-error: false
@@ -48,6 +42,6 @@ jobs:
           key: ${{ runner.os }}-${{ github.job }}-${{ hashFiles('integration-test/**/Cargo.toml', 'integration-test/**/Cargo.lock', 'integration-test/bins/rust-toolchain.toml') }}
       # Have all the "copying into Nix store" messages in a dedicated step for
       # better log visibility.
-      - run: nix-shell --run "echo OK"
+      - run: nix develop --command bash -c "echo OK"
       # Now, run the actual test.
-      - run: nix-shell --run run-integrationtest
+      - run: nix develop --command bash -c "run-integrationtest"
diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 3c914f55..edc6336e 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -24,7 +24,7 @@ jobs:
     name: build (msrv)
     uses: ./.github/workflows/_build-rust.yml
     with:
-      rust-version: 1.75.0 # MSRV
+      rust-version: 1.85.0 # MSRV
       do-style-check: false
       features: builder
 
@@ -42,7 +42,7 @@ jobs:
     with:
       rust-version: nightly
       do-style-check: false
-      features: builder,unstable
+      features: builder
 
   ### no-std Build   #########################
   build_nostd_msrv:
@@ -50,7 +50,7 @@ jobs:
     needs: build_msrv
     uses: ./.github/workflows/_build-rust.yml
     with:
-      rust-version: 1.75.0 # MSRV
+      rust-version: 1.85.0 # MSRV
       do-style-check: false
       rust-target: thumbv7em-none-eabihf
       features: builder
@@ -99,7 +99,7 @@ jobs:
       rust-version: nightly
       do-style-check: false
       rust-target: thumbv7em-none-eabihf
-      features: builder,unstable
+      features: builder
 
   ### Style Checks + Doc #####################
   style_msrv:
@@ -107,7 +107,7 @@ jobs:
     needs: build_msrv
     uses: ./.github/workflows/_build-rust.yml
     with:
-      rust-version: 1.75.0 # MSRV
+      rust-version: 1.85.0 # MSRV
       do-style-check: true
       do-test: false
       features: builder
@@ -130,7 +130,7 @@ jobs:
       rust-version: nightly
       do-style-check: true
       do-test: false
-      features: builder,unstable
+      features: builder
 
   miri:
     name: tests with miri (nightly)
@@ -141,4 +141,4 @@ jobs:
       do-style-check: false
       do-test: false
       do-miri: true
-      features: builder,unstable
+      features: builder
diff --git a/Cargo.lock b/Cargo.lock
index 7a7e3aaf..71d17e97 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,49 +1,28 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "bitflags"
-version = "2.9.0"
+version = "2.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c8214115b7bf84099f1309324e63141d4c5d7cc26862f97a0a857dbefe165bd"
-
-[[package]]
-name = "derive_more"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4a9b99b9cbbe49445b21764dc0625032a89b145a2642e67603e1c936f5458d05"
-dependencies = [
- "derive_more-impl",
-]
-
-[[package]]
-name = "derive_more-impl"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb7330aeadfbe296029522e6c40f315320aba36fc43a5b3632f3795348f3bd22"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.77",
- "unicode-xid",
-]
+checksum = "1b8e56985ec62d17e9c1001dc89c88ecd7dc08e47eba5ec7c29c7b5eeecde967"
 
 [[package]]
 name = "log"
-version = "0.4.22"
+version = "0.4.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
+checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
 
 [[package]]
 name = "multiboot2"
 version = "0.23.1"
 dependencies = [
  "bitflags",
- "derive_more",
  "log",
  "multiboot2-common",
- "ptr_meta",
+ "ptr_meta 0.3.0",
+ "thiserror",
  "uefi-raw",
 ]
 
@@ -51,26 +30,26 @@ dependencies = [
 name = "multiboot2-common"
 version = "0.2.1"
 dependencies = [
- "derive_more",
- "ptr_meta",
+ "ptr_meta 0.3.0",
+ "thiserror",
 ]
 
 [[package]]
 name = "multiboot2-header"
 version = "0.6.0"
 dependencies = [
- "derive_more",
  "log",
  "multiboot2",
  "multiboot2-common",
- "ptr_meta",
+ "ptr_meta 0.3.0",
+ "thiserror",
 ]
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.86"
+version = "1.0.95"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e719e8df665df0d1c8fbfd238015744736151d4445ec0836b8e628aae103b77"
+checksum = "02b3e5e68a3a1a02aad3ec490a98007cbc13c37cbe84a3cd7b8e406d76e7f778"
 dependencies = [
  "unicode-ident",
 ]
@@ -81,7 +60,16 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bcada80daa06c42ed5f48c9a043865edea5dc44cbf9ac009fda3b89526e28607"
 dependencies = [
- "ptr_meta_derive",
+ "ptr_meta_derive 0.2.0",
+]
+
+[[package]]
+name = "ptr_meta"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe9e76f66d3f9606f44e45598d155cb13ecf09f4a28199e48daf8c8fc937ea90"
+dependencies = [
+ "ptr_meta_derive 0.3.0",
 ]
 
 [[package]]
@@ -95,11 +83,22 @@ dependencies = [
  "syn 1.0.109",
 ]
 
+[[package]]
+name = "ptr_meta_derive"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca414edb151b4c8d125c12566ab0d74dc9cdba36fb80eb7b848c15f495fd32d1"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.101",
+]
+
 [[package]]
 name = "quote"
-version = "1.0.37"
+version = "1.0.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
+checksum = "1885c039570dc00dcb4ff087a89e185fd56bae234ddc7f056a945bf36467248d"
 dependencies = [
  "proc-macro2",
 ]
@@ -117,15 +116,35 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.77"
+version = "2.0.101"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f35bcdf61fd8e7be6caf75f429fdca8beb3ed76584befb503b1569faee373ed"
+checksum = "8ce2b7fc941b3a24138a0a7cf8e858bfc6a992e7978a068a5c760deb0ed43caf"
 dependencies = [
  "proc-macro2",
  "quote",
  "unicode-ident",
 ]
 
+[[package]]
+name = "thiserror"
+version = "2.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "567b8a2dae586314f7be2a752ec7474332959c6460e02bde30d702a66d488708"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "2.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f7cf42b4507d8ea322120659672cf1b9dbb93f8f2d4ecfd6e51350ff5b17a1d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.101",
+]
+
 [[package]]
 name = "uefi-raw"
 version = "0.8.0"
@@ -133,24 +152,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b463030b802e1265a3800fab24df95d3229c202c2e408832a206f05b4d1496ca"
 dependencies = [
  "bitflags",
- "ptr_meta",
+ "ptr_meta 0.2.0",
  "uguid",
 ]
 
 [[package]]
 name = "uguid"
-version = "2.2.0"
+version = "2.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab14ea9660d240e7865ce9d54ecdbd1cd9fa5802ae6f4512f093c7907e921533"
+checksum = "0c8352f8c05e47892e7eaf13b34abd76a7f4aeaf817b716e88789381927f199c"
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e91b56cd4cadaeb79bbf1a5645f6b4f8dc5bde8834ad5894a8db35fda9efa1fe"
-
-[[package]]
-name = "unicode-xid"
-version = "0.2.5"
+version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "229730647fbc343e3a80e463c1db7f78f3855d3f3739bee0dda773c9a037c90a"
+checksum = "5a5f39404a5da50712a4c1eecf25e90dd62b613502b7e925fd4e4d19b5c96512"
diff --git a/Cargo.toml b/Cargo.toml
index 2e5d4669..99c53d0b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,22 +1,27 @@
 [workspace]
 resolver = "2"
 members = [
-    "multiboot2",
-    "multiboot2-common",
-    "multiboot2-header",
+  "multiboot2",
+  "multiboot2-common",
+  "multiboot2-header",
 ]
 exclude = [
-    "integration-test"
+  "integration-test"
 ]
+package.rust-version = "1.85.0"
+package.edition = "2024"
+package.license = "MIT/Apache-2.0"
 
 [workspace.dependencies]
-bitflags = "2.9.0"
-derive_more = { version = "1.0.0", default-features = false, features = ["display"] }
+bitflags = "2.9.1"
 log = { version = "~0.4", default-features = false }
+ptr_meta = { version = "~0.3", default-features = false, features = ["derive"] }
+thiserror = { version = "2.0.12", default-features = false }
+
+# Intra-workspace dependencies of upstream crates: always point to the latest
+# stable version
 multiboot2 = { version = "0.23.1", default-features = false }
 multiboot2-common = { version = "0.2.1", default-features = false }
-# Warn: 0.3 has multiple very breaking changes
-ptr_meta = { version = "~0.2", default-features = false }
 
 # This way, the corresponding crate dependency can be normalley referenced by
 # version, while still the repository version is used transparently during local
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 00000000..cd3f1694
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1748437600,
+        "narHash": "sha256-hYKMs3ilp09anGO7xzfGs3JqEgUqFMnZ8GMAqI6/k04=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "7282cb574e0607e65224d33be8241eae7cfe0979",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-25.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 00000000..f685eec5
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,29 @@
+{
+  description = "multiboot2-rs";
+
+  inputs = {
+    # We follow the latest stable release of nixpkgs
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-25.05";
+  };
+
+  outputs =
+    inputs@{ self, nixpkgs, ... }:
+    let
+      # Systems definition for dev shells and exported packages,
+      # independent of the NixOS configurations and modules defined here. We
+      # just use "every system" here to not restrict any user. However, it
+      # likely happens that certain packages don't build for/under certain
+      # systems.
+      systems = nixpkgs.lib.systems.flakeExposed;
+      forAllSystems =
+        function: nixpkgs.lib.genAttrs systems (system: function nixpkgs.legacyPackages.${system});
+    in
+    {
+      formatter = forAllSystems (pkgs: pkgs.nixfmt-rfc-style);
+      devShells = forAllSystems (pkgs: {
+        default = import ./shell.nix {
+          inherit pkgs;
+        };
+      });
+    };
+}
diff --git a/integration-test/bins/Cargo.lock b/integration-test/bins/Cargo.lock
index f67edea9..0f796815 100644
--- a/integration-test/bins/Cargo.lock
+++ b/integration-test/bins/Cargo.lock
@@ -1,18 +1,18 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "anyhow"
-version = "1.0.86"
+version = "1.0.98"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b3d1d046238990b9cf5bcde22a3fb3584ee5cf65fb2765f454ed428c7a0063da"
+checksum = "e16d2d3311acee920a9eb8d33b8cbc1787ce4a264e85f964c2404b969bdcd487"
 
 [[package]]
 name = "autocfg"
-version = "1.3.0"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c4b4d0bd25bd0b74681c0ad21497610ce1b7c91b1022cd21c80c6fbdd9476b0"
+checksum = "ace50bade8e6234aa140d9a2f552bbee1db4d353f69b8217bc503490fc1a9f26"
 
 [[package]]
 name = "bit_field"
@@ -28,36 +28,15 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
 name = "bitflags"
-version = "2.6.0"
+version = "2.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
-
-[[package]]
-name = "derive_more"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4a9b99b9cbbe49445b21764dc0625032a89b145a2642e67603e1c936f5458d05"
-dependencies = [
- "derive_more-impl",
-]
-
-[[package]]
-name = "derive_more-impl"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb7330aeadfbe296029522e6c40f315320aba36fc43a5b3632f3795348f3bd22"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.74",
- "unicode-xid",
-]
+checksum = "1b8e56985ec62d17e9c1001dc89c88ecd7dc08e47eba5ec7c29c7b5eeecde967"
 
 [[package]]
 name = "either"
-version = "1.13.0"
+version = "1.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "60b1af1c220855b6ceac025d3f6ecdd2b7c4894bfe9cd9bda4fbb4bc7c0d4cf0"
+checksum = "48c757948c5ede0e46177b7add2e67155f70e33c07fea8284df6576da70b3719"
 
 [[package]]
 name = "elf_rs"
@@ -65,7 +44,7 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "894d710b6b07dae25ce69f9227ec2ffa3a3f71dc7f071acea3e1928ab4aeafdf"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.9.1",
  "num-traits",
 ]
 
@@ -81,9 +60,9 @@ dependencies = [
 
 [[package]]
 name = "lock_api"
-version = "0.4.12"
+version = "0.4.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07af8b9cdd281b7915f413fa73f29ebd5d55d0d3f0155584dade1ff18cea1b17"
+checksum = "96936507f153605bddfcda068dd804796c84324ed2510809e5b2a624c81da765"
 dependencies = [
  "autocfg",
  "scopeguard",
@@ -91,9 +70,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.22"
+version = "0.4.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
+checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
 
 [[package]]
 name = "multiboot"
@@ -108,11 +87,11 @@ dependencies = [
 name = "multiboot2"
 version = "0.23.1"
 dependencies = [
- "bitflags 2.6.0",
- "derive_more",
+ "bitflags 2.9.1",
  "log",
  "multiboot2-common",
- "ptr_meta",
+ "ptr_meta 0.3.0",
+ "thiserror",
  "uefi-raw",
 ]
 
@@ -120,19 +99,19 @@ dependencies = [
 name = "multiboot2-common"
 version = "0.2.1"
 dependencies = [
- "derive_more",
- "ptr_meta",
+ "ptr_meta 0.3.0",
+ "thiserror",
 ]
 
 [[package]]
 name = "multiboot2-header"
 version = "0.6.0"
 dependencies = [
- "derive_more",
  "log",
  "multiboot2",
  "multiboot2-common",
- "ptr_meta",
+ "ptr_meta 0.3.0",
+ "thiserror",
 ]
 
 [[package]]
@@ -178,9 +157,9 @@ checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.86"
+version = "1.0.95"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e719e8df665df0d1c8fbfd238015744736151d4445ec0836b8e628aae103b77"
+checksum = "02b3e5e68a3a1a02aad3ec490a98007cbc13c37cbe84a3cd7b8e406d76e7f778"
 dependencies = [
  "unicode-ident",
 ]
@@ -191,7 +170,16 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bcada80daa06c42ed5f48c9a043865edea5dc44cbf9ac009fda3b89526e28607"
 dependencies = [
- "ptr_meta_derive",
+ "ptr_meta_derive 0.2.0",
+]
+
+[[package]]
+name = "ptr_meta"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe9e76f66d3f9606f44e45598d155cb13ecf09f4a28199e48daf8c8fc937ea90"
+dependencies = [
+ "ptr_meta_derive 0.3.0",
 ]
 
 [[package]]
@@ -205,6 +193,17 @@ dependencies = [
  "syn 1.0.109",
 ]
 
+[[package]]
+name = "ptr_meta_derive"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca414edb151b4c8d125c12566ab0d74dc9cdba36fb80eb7b848c15f495fd32d1"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.101",
+]
+
 [[package]]
 name = "qemu-exit"
 version = "3.0.2"
@@ -213,9 +212,9 @@ checksum = "8bb0fd6580eeed0103c054e3fba2c2618ff476943762f28a645b63b8692b21c9"
 
 [[package]]
 name = "quote"
-version = "1.0.36"
+version = "1.0.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0fa76aaf39101c457836aec0ce2316dbdc3ab723cdda1c6bd4e6ad4208acaca7"
+checksum = "1885c039570dc00dcb4ff087a89e185fd56bae234ddc7f056a945bf36467248d"
 dependencies = [
  "proc-macro2",
 ]
@@ -257,43 +256,57 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.74"
+version = "2.0.101"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1fceb41e3d546d0bd83421d3409b1460cc7444cd389341a4c880fe7a042cb3d7"
+checksum = "8ce2b7fc941b3a24138a0a7cf8e858bfc6a992e7978a068a5c760deb0ed43caf"
 dependencies = [
  "proc-macro2",
  "quote",
  "unicode-ident",
 ]
 
+[[package]]
+name = "thiserror"
+version = "2.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "567b8a2dae586314f7be2a752ec7474332959c6460e02bde30d702a66d488708"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "2.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f7cf42b4507d8ea322120659672cf1b9dbb93f8f2d4ecfd6e51350ff5b17a1d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.101",
+]
+
 [[package]]
 name = "uefi-raw"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b463030b802e1265a3800fab24df95d3229c202c2e408832a206f05b4d1496ca"
 dependencies = [
- "bitflags 2.6.0",
- "ptr_meta",
+ "bitflags 2.9.1",
+ "ptr_meta 0.2.0",
  "uguid",
 ]
 
 [[package]]
 name = "uguid"
-version = "2.2.0"
+version = "2.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab14ea9660d240e7865ce9d54ecdbd1cd9fa5802ae6f4512f093c7907e921533"
+checksum = "0c8352f8c05e47892e7eaf13b34abd76a7f4aeaf817b716e88789381927f199c"
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
-
-[[package]]
-name = "unicode-xid"
-version = "0.2.5"
+version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "229730647fbc343e3a80e463c1db7f78f3855d3f3739bee0dda773c9a037c90a"
+checksum = "5a5f39404a5da50712a4c1eecf25e90dd62b613502b7e925fd4e4d19b5c96512"
 
 [[package]]
 name = "util"
diff --git a/integration-test/bins/Cargo.toml b/integration-test/bins/Cargo.toml
index 05bf49d6..af50178b 100644
--- a/integration-test/bins/Cargo.toml
+++ b/integration-test/bins/Cargo.toml
@@ -14,8 +14,8 @@ lto = true
 [workspace.dependencies]
 anyhow = { version = "1.0", default-features = false }
 log = { version = "0.4", default-features = false }
-multiboot2 = { path = "../../multiboot2", features = ["builder", "unstable"] }
-multiboot2-header = { path = "../../multiboot2-header", features = ["builder", "unstable"] }
+multiboot2 = { path = "../../multiboot2", features = ["builder"] }
+multiboot2-header = { path = "../../multiboot2-header", features = ["builder"] }
 good_memory_allocator = "0.1"
 util = { path = "./util" }
 
diff --git a/integration-test/bins/multiboot2_chainloader/Cargo.toml b/integration-test/bins/multiboot2_chainloader/Cargo.toml
index e3089f53..68bbcb82 100644
--- a/integration-test/bins/multiboot2_chainloader/Cargo.toml
+++ b/integration-test/bins/multiboot2_chainloader/Cargo.toml
@@ -2,7 +2,7 @@
 name = "multiboot2_chainloader"
 description = "Integrationtest: Multiboot2 chainloader"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 publish = false
 
 [dependencies]
diff --git a/integration-test/bins/multiboot2_chainloader/src/main.rs b/integration-test/bins/multiboot2_chainloader/src/main.rs
index 59c2940c..5462c579 100644
--- a/integration-test/bins/multiboot2_chainloader/src/main.rs
+++ b/integration-test/bins/multiboot2_chainloader/src/main.rs
@@ -1,6 +1,5 @@
 #![no_main]
 #![no_std]
-#![feature(error_in_core)]
 
 mod loader;
 mod multiboot;
@@ -16,7 +15,7 @@ core::arch::global_asm!(include_str!("start.S"), options(att_syntax));
 
 /// Entry into the Rust code from assembly using the x86 SystemV calling
 /// convention.
-#[no_mangle]
+#[unsafe(no_mangle)]
 fn rust_entry(multiboot_magic: u32, multiboot_hdr: *const u32) -> ! {
     init_environment();
     let x = 0.12 + 0.56;
diff --git a/integration-test/bins/multiboot2_chainloader/src/multiboot.rs b/integration-test/bins/multiboot2_chainloader/src/multiboot.rs
index 0a0bd5f6..38b2e934 100644
--- a/integration-test/bins/multiboot2_chainloader/src/multiboot.rs
+++ b/integration-test/bins/multiboot2_chainloader/src/multiboot.rs
@@ -25,7 +25,7 @@ struct Mem;
 impl MemoryManagement for Mem {
     unsafe fn paddr_to_slice(&self, addr: PAddr, size: usize) -> Option<&'static [u8]> {
         let ptr = addr as *const u64 as *const u8;
-        Some(slice::from_raw_parts(ptr, size))
+        Some(unsafe { slice::from_raw_parts(ptr, size) })
     }
 
     // If you only want to read fields, you can simply return `None`.
diff --git a/integration-test/bins/multiboot2_payload/Cargo.toml b/integration-test/bins/multiboot2_payload/Cargo.toml
index 46946abf..d0c3a2e7 100644
--- a/integration-test/bins/multiboot2_payload/Cargo.toml
+++ b/integration-test/bins/multiboot2_payload/Cargo.toml
@@ -2,7 +2,7 @@
 name = "multiboot2_payload"
 description = "Integrationtest: Multiboot2 payload"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 publish = false
 
 [dependencies]
diff --git a/integration-test/bins/multiboot2_payload/src/main.rs b/integration-test/bins/multiboot2_payload/src/main.rs
index 4599bc35..203354a5 100644
--- a/integration-test/bins/multiboot2_payload/src/main.rs
+++ b/integration-test/bins/multiboot2_payload/src/main.rs
@@ -1,6 +1,5 @@
 #![no_main]
 #![no_std]
-#![feature(error_in_core)]
 
 extern crate alloc;
 
@@ -16,7 +15,7 @@ use util::{init_environment, qemu_exit_success};
 mod verify;
 
 /// Entry into the Rust code from assembly.
-#[no_mangle]
+#[unsafe(no_mangle)]
 fn rust_entry(multiboot2_magic: u32, multiboot2_hdr: u32) -> ! {
     main(multiboot2_magic, multiboot2_hdr).expect("Should run multiboot2 integration test");
     log::info!("Integration test finished successfully");
diff --git a/integration-test/bins/rust-toolchain.toml b/integration-test/bins/rust-toolchain.toml
index 4349337f..a89ae50a 100644
--- a/integration-test/bins/rust-toolchain.toml
+++ b/integration-test/bins/rust-toolchain.toml
@@ -1,5 +1,5 @@
 [toolchain]
-channel = "nightly-2024-04-30" # rustc 1.80-nightly
+channel = "nightly-2025-05-31" # rustc 1.89-nightly
 profile = "default"
 components = [
     "rust-src",
diff --git a/multiboot2-common/CHANGELOG.md b/multiboot2-common/CHANGELOG.md
index 231db579..06143f8f 100644
--- a/multiboot2-common/CHANGELOG.md
+++ b/multiboot2-common/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+- **Breaking:** Removed the optional `unstable` feature (required nightly)
+  - `core::error::Error` is now implemented unconditionally
+- **Breaking:** The MSRV is now 1.81
+
 ## v0.2.1 (2024-09-19)
 
 - Documentation improvements
diff --git a/multiboot2-common/Cargo.toml b/multiboot2-common/Cargo.toml
index 1f866145..bd97e807 100644
--- a/multiboot2-common/Cargo.toml
+++ b/multiboot2-common/Cargo.toml
@@ -5,33 +5,32 @@ Common helpers for the `multiboot2` and `multiboot2-header` crates.
 """
 version = "0.2.1"
 authors = [
-    "Philipp Schuster <phip1611@gmail.com>"
+  "Philipp Schuster <phip1611@gmail.com>"
 ]
-license = "MIT/Apache-2.0"
-edition = "2021"
 categories = [
-    "no-std",
-    "no-std::no-alloc",
+  "no-std",
+  "no-std::no-alloc",
 ]
 keywords = [
-    "Multiboot2"
+  "Multiboot2"
 ]
 readme = "README.md"
 homepage = "https://github.com/rust-osdev/multiboot2/tree/main/multiboot2-common"
 repository = "https://github.com/rust-osdev/multiboot2"
 documentation = "https://docs.rs/multiboot2-common"
-rust-version = "1.75"
+edition.workspace = true
+license.workspace = true
+rust-version.workspace = true
 
 [features]
 default = ["builder"]
 alloc = []
 builder = ["alloc"]
-unstable = []
 
 
 [dependencies]
-derive_more.workspace = true
 ptr_meta.workspace = true
+thiserror.workspace = true
 
 [package.metadata.docs.rs]
 all-features = true
diff --git a/multiboot2-common/README.md b/multiboot2-common/README.md
index 5c6aa723..b6dbe506 100644
--- a/multiboot2-common/README.md
+++ b/multiboot2-common/README.md
@@ -46,7 +46,7 @@ to first study the inner box (`multiboot2-common`) and then study how types from
 
 ## MSRV
 
-The MSRV is 1.75.0 stable.
+The MSRV is 1.85.0 stable.
 
 ## License & Contribution
 
diff --git a/multiboot2-common/src/boxed.rs b/multiboot2-common/src/boxed.rs
index 24a8906d..6e79ba67 100644
--- a/multiboot2-common/src/boxed.rs
+++ b/multiboot2-common/src/boxed.rs
@@ -1,6 +1,6 @@
 //! Module for [`new_boxed`].
 
-use crate::{increase_to_alignment, Header, MaybeDynSized, ALIGNMENT};
+use crate::{ALIGNMENT, Header, MaybeDynSized, increase_to_alignment};
 use alloc::boxed::Box;
 use core::alloc::Layout;
 use core::mem;
@@ -88,8 +88,8 @@ pub fn clone_dyn<T: MaybeDynSized<Metadata = usize> + ?Sized>(tag: &T) -> Box<T>
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::test_utils::{DummyDstTag, DummyTestHeader};
     use crate::Tag;
+    use crate::test_utils::{DummyDstTag, DummyTestHeader};
 
     #[test]
     fn test_new_boxed() {
diff --git a/multiboot2-common/src/bytes_ref.rs b/multiboot2-common/src/bytes_ref.rs
index f2291408..13b4e389 100644
--- a/multiboot2-common/src/bytes_ref.rs
+++ b/multiboot2-common/src/bytes_ref.rs
@@ -1,6 +1,6 @@
 //! Module for [`BytesRef`].
 
-use crate::{Header, MemoryError, ALIGNMENT};
+use crate::{ALIGNMENT, Header, MemoryError};
 use core::marker::PhantomData;
 use core::mem;
 use core::ops::Deref;
diff --git a/multiboot2-common/src/iter.rs b/multiboot2-common/src/iter.rs
index 775dedf8..75e5c78c 100644
--- a/multiboot2-common/src/iter.rs
+++ b/multiboot2-common/src/iter.rs
@@ -2,7 +2,7 @@
 //! Multiboot2 information tags and iterating Multiboot2 header tags is the
 //! same.
 
-use crate::{increase_to_alignment, DynSizedStructure, Header, ALIGNMENT};
+use crate::{ALIGNMENT, DynSizedStructure, Header, increase_to_alignment};
 use core::marker::PhantomData;
 use core::mem;
 
@@ -86,8 +86,8 @@ impl<'a, H: Header + 'a> Iterator for TagIter<'a, H> {
 
 #[cfg(test)]
 mod tests {
-    use crate::test_utils::{AlignedBytes, DummyTestHeader};
     use crate::TagIter;
+    use crate::test_utils::{AlignedBytes, DummyTestHeader};
     use core::borrow::Borrow;
 
     #[test]
diff --git a/multiboot2-common/src/lib.rs b/multiboot2-common/src/lib.rs
index 5d862e3f..2e38a688 100644
--- a/multiboot2-common/src/lib.rs
+++ b/multiboot2-common/src/lib.rs
@@ -29,7 +29,7 @@
 //! - `BootInformationHeader` implementing [`Header`]
 //! - `BootInformation` wrapping [`DynSizedStructure`]
 //! - `type TagIter<'a> = multiboot2_common::TagIter<'a, TagHeader>`
-//!    ([`TagIter`])
+//!   ([`TagIter`])
 //! - `TagHeader` implementing [`Header`]
 //! - Structs for each tag, each implementing [`MaybeDynSized`]
 //!
@@ -220,7 +220,6 @@
 //! [`Layout`]: core::alloc::Layout
 
 #![no_std]
-#![cfg_attr(feature = "unstable", feature(error_in_core))]
 // --- BEGIN STYLE CHECKS ---
 #![deny(
     clippy::all,
@@ -261,6 +260,7 @@ use core::mem;
 use core::ptr;
 use core::ptr::NonNull;
 use core::slice;
+use thiserror::Error;
 
 /// The alignment of all Multiboot2 data structures.
 pub const ALIGNMENT: usize = 8;
@@ -424,27 +424,29 @@ impl<H: Header> DynSizedStructure<H> {
 }
 
 /// Errors that may occur when working with memory.
-#[derive(Copy, Clone, Debug, Ord, PartialOrd, Eq, PartialEq, Hash, derive_more::Display)]
+#[derive(Copy, Clone, Debug, Ord, PartialOrd, Eq, PartialEq, Hash, Error)]
 pub enum MemoryError {
     /// The memory points to null.
+    #[error("memory points to null")]
     Null,
     /// The memory must be at least [`ALIGNMENT`]-aligned.
+    #[error("memory is not properly aligned")]
     WrongAlignment,
     /// The memory must cover at least the length of the sized structure header
     /// type.
+    #[error("memory range is shorter than the size of the header structure")]
     ShorterThanHeader,
     /// The buffer misses the terminating padding to the next alignment
     /// boundary. The padding is relevant to satisfy Rustc/Miri, but also the
     /// spec mandates that the padding is added.
+    #[error("memory is missing required padding")]
     MissingPadding,
     /// The size-property has an illegal value that can't be fulfilled with the
     /// given bytes.
+    #[error("the header reports an invalid total size")]
     InvalidReportedTotalSize,
 }
 
-#[cfg(feature = "unstable")]
-impl core::error::Error for MemoryError {}
-
 /// Increases the given size to the next alignment boundary, if it is not a
 /// multiple of the alignment yet.
 ///
diff --git a/multiboot2-header/CHANGELOG.md b/multiboot2-header/CHANGELOG.md
index 8ddb96c7..4484c1e7 100644
--- a/multiboot2-header/CHANGELOG.md
+++ b/multiboot2-header/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+- **Breaking:** Removed the optional `unstable` feature (required nightly)
+  - `core::error::Error` is now implemented unconditionally
+- **Breaking:** The MSRV is now 1.81
+
 ## v0.6.0 (2024-09-17)
 
 - dependency updates
@@ -61,7 +65,7 @@ without Undefined Behavior.
 - **BREAKING** `HeaderBuilder::build` now returns a value of type `HeaderBytes`
   The old builder could produce misaligned structures.
 - added the optional `unstable` feature (requires nightly)
-    - implement `core::error::Error` for `LoadError`
+  - implement `core::error::Error` for `LoadError`
 
 ## 0.2.0 (2022-05-03) (**YANKED**)
 
diff --git a/multiboot2-header/Cargo.toml b/multiboot2-header/Cargo.toml
index b5d33ea3..c6cdad31 100644
--- a/multiboot2-header/Cargo.toml
+++ b/multiboot2-header/Cargo.toml
@@ -8,20 +8,18 @@ the corresponding structures.
 """
 version = "0.6.0"
 authors = [
-    "Philipp Schuster <phip1611@gmail.com>"
+  "Philipp Schuster <phip1611@gmail.com>"
 ]
-license = "MIT/Apache-2.0"
-edition = "2021"
 categories = [
-    "no-std",
-    "no-std::no-alloc",
-    "parsing",
+  "no-std",
+  "no-std::no-alloc",
+  "parsing",
 ]
 keywords = [
-    "Multiboot2",
-    "kernel",
-    "boot",
-    "bootloader",
+  "Multiboot2",
+  "kernel",
+  "boot",
+  "bootloader",
 ]
 # without this, sometimes crates.io doesn't show the preview of the README
 # I expeciended this multiple times in the past
@@ -29,7 +27,9 @@ readme = "README.md"
 homepage = "https://github.com/rust-osdev/multiboot2/tree/main/multiboot2-header"
 repository = "https://github.com/rust-osdev/multiboot2"
 documentation = "https://docs.rs/multiboot2-header"
-rust-version = "1.75"
+edition.workspace = true
+license.workspace = true
+rust-version.workspace = true
 
 [[example]]
 name = "minimal"
@@ -39,15 +39,13 @@ required-features = ["builder"]
 default = ["builder"]
 alloc = ["multiboot2-common/alloc"]
 builder = ["alloc", "multiboot2-common/builder"]
-# Nightly-only features, which will eventually be stabilized.
-unstable = ["multiboot2-common/unstable"]
 
 [dependencies]
-derive_more.workspace = true
 log.workspace = true
 multiboot2-common.workspace = true
 multiboot2.workspace = true
 ptr_meta.workspace = true
+thiserror.workspace = true
 
 [package.metadata.docs.rs]
 all-features = true
diff --git a/multiboot2-header/README.md b/multiboot2-header/README.md
index 170615f6..bb6407ce 100644
--- a/multiboot2-header/README.md
+++ b/multiboot2-header/README.md
@@ -46,25 +46,25 @@ use multiboot2_header::{HeaderTagFlag, HeaderTagISA, MbiTagType, RelocatableHead
 
 /// Small example that creates a Multiboot2 header and parses it afterwards.
 fn main() {
-    // We create a Multiboot2 header during runtime here. A practical example is that your
-    // program gets the header from a file and parses it afterwards.
-    let mb2_hdr_bytes = Multiboot2HeaderBuilder::new(HeaderTagISA::I386)
-        .relocatable_tag(RelocatableHeaderTag::new(
-            HeaderTagFlag::Required,
-            0x1337,
-            0xdeadbeef,
-            4096,
-            RelocatableHeaderTagPreference::None,
-        ))
-        .information_request_tag(
-            InformationRequestHeaderTagBuilder::new(HeaderTagFlag::Required)
-                .add_irs(&[MbiTagType::Cmdline, MbiTagType::BootLoaderName]),
-        )
-        .build();
-
-    // Cast bytes in vector to Multiboot2 information structure
-    let mb2_hdr = unsafe { Multiboot2Header::from_addr(mb2_hdr_bytes.as_ptr().cast()) };
-    println!("{:#?}", mb2_hdr);
+  // We create a Multiboot2 header during runtime here. A practical example is that your
+  // program gets the header from a file and parses it afterwards.
+  let mb2_hdr_bytes = Multiboot2HeaderBuilder::new(HeaderTagISA::I386)
+    .relocatable_tag(RelocatableHeaderTag::new(
+      HeaderTagFlag::Required,
+      0x1337,
+      0xdeadbeef,
+      4096,
+      RelocatableHeaderTagPreference::None,
+    ))
+    .information_request_tag(
+      InformationRequestHeaderTagBuilder::new(HeaderTagFlag::Required)
+        .add_irs(&[MbiTagType::Cmdline, MbiTagType::BootLoaderName]),
+    )
+    .build();
+
+  // Cast bytes in vector to Multiboot2 information structure
+  let mb2_hdr = unsafe { Multiboot2Header::from_addr(mb2_hdr_bytes.as_ptr().cast()) };
+  println!("{:#?}", mb2_hdr);
 }
 ```
 
@@ -75,7 +75,7 @@ include it like this:
 
 ```
 #[used]
-#[no_mangle]
+#[unsafe(no_mangle)]
 #[link_section = ".text.multiboot2_header"]
 static MULTIBOOT2_HDR: [u8; 64] = *include_bytes!("mb2_hdr_dump.bin");
 ```
@@ -85,7 +85,7 @@ bytes of the ELF. See Multiboot2 specification.
 
 ## MSRV
 
-The MSRV is 1.75.0 stable.
+The MSRV is 1.85.0 stable.
 
 ## License & Contribution
 
diff --git a/multiboot2-header/examples/minimal.rs b/multiboot2-header/examples/minimal.rs
index e77c02bc..5dcabd00 100644
--- a/multiboot2-header/examples/minimal.rs
+++ b/multiboot2-header/examples/minimal.rs
@@ -31,5 +31,5 @@ fn main() {
     let ptr = mb2_hdr_bytes.as_bytes().as_ptr();
     let mb2_hdr = unsafe { Multiboot2Header::load(ptr.cast()) };
     let mb2_hdr = mb2_hdr.unwrap();
-    println!("{:#?}", mb2_hdr);
+    println!("{mb2_hdr:#?}");
 }
diff --git a/multiboot2-header/src/builder.rs b/multiboot2-header/src/builder.rs
index 9017154a..1c9598d8 100644
--- a/multiboot2-header/src/builder.rs
+++ b/multiboot2-header/src/builder.rs
@@ -7,7 +7,7 @@ use crate::{
 };
 use alloc::boxed::Box;
 use alloc::vec::Vec;
-use multiboot2_common::{new_boxed, DynSizedStructure, MaybeDynSized};
+use multiboot2_common::{DynSizedStructure, MaybeDynSized, new_boxed};
 
 /// Builder for a Multiboot2 header information.
 #[derive(Debug)]
diff --git a/multiboot2-header/src/header.rs b/multiboot2-header/src/header.rs
index 53963e5e..66c127a0 100644
--- a/multiboot2-header/src/header.rs
+++ b/multiboot2-header/src/header.rs
@@ -4,12 +4,11 @@ use crate::{
     HeaderTagType, InformationRequestHeaderTag, ModuleAlignHeaderTag, RelocatableHeaderTag,
     TagIter,
 };
-#[cfg(feature = "unstable")]
-use core::error::Error;
 use core::fmt::{Debug, Formatter};
 use core::mem::size_of;
 use core::ptr::NonNull;
-use multiboot2_common::{DynSizedStructure, Header, MemoryError, Tag, ALIGNMENT};
+use multiboot2_common::{ALIGNMENT, DynSizedStructure, Header, MemoryError, Tag};
+use thiserror::Error;
 
 /// Magic value for a [`Multiboot2Header`], as defined by the spec.
 pub const MAGIC: u32 = 0xe85250d6;
@@ -39,7 +38,7 @@ impl<'a> Multiboot2Header<'a> {
     /// Multiboot2 header pointer.
     pub unsafe fn load(ptr: *const Multiboot2BasicHeader) -> Result<Self, LoadError> {
         let ptr = NonNull::new(ptr.cast_mut()).ok_or(LoadError::Memory(MemoryError::Null))?;
-        let inner = DynSizedStructure::ref_from_ptr(ptr).map_err(LoadError::Memory)?;
+        let inner = unsafe { DynSizedStructure::ref_from_ptr(ptr).map_err(LoadError::Memory)? };
         let this = Self(inner);
 
         let header = this.0.header();
@@ -226,25 +225,18 @@ impl Debug for Multiboot2Header<'_> {
 
 /// Errors that occur when a chunk of memory can't be parsed as
 /// [`Multiboot2Header`].
-#[derive(Copy, Clone, Debug, derive_more::Display, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Error)]
 pub enum LoadError {
     /// The provided checksum does not match the expected value.
+    #[error("checksum does not match expected value")]
     ChecksumMismatch,
     /// The header does not contain the correct magic number.
+    #[error("header does not contain expected magic value")]
     MagicNotFound,
     /// The provided memory can't be parsed as [`Multiboot2Header`].
     /// See [`MemoryError`].
-    Memory(MemoryError),
-}
-
-#[cfg(feature = "unstable")]
-impl Error for LoadError {
-    fn source(&self) -> Option<&(dyn Error + 'static)> {
-        match self {
-            Self::Memory(inner) => Some(inner),
-            _ => None,
-        }
-    }
+    #[error("memory can't be parsed as multiboot2 header")]
+    Memory(#[source] MemoryError),
 }
 
 /// The "basic" Multiboot2 header. This means only the properties, that are known during
diff --git a/multiboot2-header/src/lib.rs b/multiboot2-header/src/lib.rs
index d4066dca..e2a6974e 100644
--- a/multiboot2-header/src/lib.rs
+++ b/multiboot2-header/src/lib.rs
@@ -23,10 +23,9 @@
 //!
 //! ## MSRV
 //!
-//! The MSRV is 1.75.0 stable.
+//! The MSRV is 1.85.0 stable.
 
 #![no_std]
-#![cfg_attr(feature = "unstable", feature(error_in_core))]
 // --- BEGIN STYLE CHECKS ---
 #![deny(
     clippy::all,
diff --git a/multiboot2/CHANGELOG.md b/multiboot2/CHANGELOG.md
index c061208e..d2f14fb0 100644
--- a/multiboot2/CHANGELOG.md
+++ b/multiboot2/CHANGELOG.md
@@ -2,6 +2,11 @@
 
 ## Unreleased
 
+- **Breaking:** Removed the optional `unstable` feature (required nightly)
+  - `core::error::Error` is now implemented unconditionally
+- **Breaking:** The MSRV is now 1.81
+- Fixed a bug causing UB in `ElfSection::name()`
+
 ## v0.23.1 (2024-10-21)
 
 - Fix wrong tag ID when using `BootdevTag::new`
@@ -15,9 +20,9 @@
 - dependency updates
 - **Breaking:** MSRV is now 1.75
 - Added missing tags along with getters for on `BootInformation`:
-    - `ApmTag`
-    - `BootdevTag`
-    - `NetworkTag`
+  - `ApmTag`
+  - `BootdevTag`
+  - `NetworkTag`
 - `BootInformation::tags` iterator is now public
 - misc metadata fixes
 
@@ -220,12 +225,12 @@ release and you'll be fine!**
 - **BREAKING** MSRV is 1.56.1
 - **BREAKING** fixed lifetime issues: `VBEInfoTag` is no longer `&static`
 - **BREAKING:** `TagType` is now split into `TagTypeId` and `TagType`
-    - `TagTypeId` is a binary-compatible form of a Multiboot2 tag id
-    - `TagType` is a higher-level abstraction for either specified or custom
-      tags
-      but not ABI compatible.
-    - There exists a seamless integration between `u32`, `TagType`, and
-      `TagTypeId` via `From` and `PartialEq`-implementations.
+  - `TagTypeId` is a binary-compatible form of a Multiboot2 tag id
+  - `TagType` is a higher-level abstraction for either specified or custom
+    tags
+    but not ABI compatible.
+  - There exists a seamless integration between `u32`, `TagType`, and
+    `TagTypeId` via `From` and `PartialEq`-implementations.
 - fixed another internal lifetime issue
 - `BootInformation::framebuffer_tag()` now returns
   `Option<Result<FramebufferTag, UnknownFramebufferType>>` instead of
@@ -258,14 +263,14 @@ release and you'll be fine!**
   This version includes a few small breaking changes that brings more safety
   when parsing strings from the
   multiboot information structure.
-    - `BootLoaderNameTag::name` now returns a Result instead of just the value
-    - `CommandLineTag::command_line` now returns a Result instead of just the
-      value
-    - `ModuleTag::cmdline` now returns a Result instead of just the value
-    - `RsdpV1Tag::signature` now returns a Result instead of an Option
-    - `RsdpV1Tag::oem_id` now returns a Result instead of an Option
-    - `RsdpV2Tag::signature` now returns a Result instead of an Option
-    - `RsdpV2Tag::oem_id` now returns a Result instead of an Option
+  - `BootLoaderNameTag::name` now returns a Result instead of just the value
+  - `CommandLineTag::command_line` now returns a Result instead of just the
+    value
+  - `ModuleTag::cmdline` now returns a Result instead of just the value
+  - `RsdpV1Tag::signature` now returns a Result instead of an Option
+  - `RsdpV1Tag::oem_id` now returns a Result instead of an Option
+  - `RsdpV2Tag::signature` now returns a Result instead of an Option
+  - `RsdpV2Tag::oem_id` now returns a Result instead of an Option
 - internal code improvements
 
 ## 0.13.3 (2022-06-03) (**YANKED**)
@@ -291,14 +296,14 @@ release and you'll be fine!**
 
 - `TagType` now implements `Eq` and `Hash`
 - internal improvements
-    - `std` can be used in tests; the crate is still `no_std`
-        - this implies that `cargo test` doesn't work on "non-standard" targets
-        - CI (Ubuntu) still works.
-    - code formatting/style
-    - sensible style checks as optional CI job
-    - `.editorconfig` file
-    - prepared co-existence of crates `multiboot2` and `multiboot2-header`
-      in a Cargo workspace inside the same repository
+  - `std` can be used in tests; the crate is still `no_std`
+    - this implies that `cargo test` doesn't work on "non-standard" targets
+    - CI (Ubuntu) still works.
+  - code formatting/style
+  - sensible style checks as optional CI job
+  - `.editorconfig` file
+  - prepared co-existence of crates `multiboot2` and `multiboot2-header`
+    in a Cargo workspace inside the same repository
 
 ## 0.12.1 (2021-08-11) (**YANKED**)
 
diff --git a/multiboot2/Cargo.toml b/multiboot2/Cargo.toml
index 608537fc..77bfb2f6 100644
--- a/multiboot2/Cargo.toml
+++ b/multiboot2/Cargo.toml
@@ -8,23 +8,21 @@ the corresponding structures.
 """
 version = "0.23.1"
 authors = [
-    "Philipp Oppermann <dev@phil-opp.com>",
-    "Calvin Lee <cyrus296@gmail.com>",
-    "Isaac Woods",
-    "Philipp Schuster <phip1611@gmail.com>"
+  "Philipp Oppermann <dev@phil-opp.com>",
+  "Calvin Lee <cyrus296@gmail.com>",
+  "Isaac Woods",
+  "Philipp Schuster <phip1611@gmail.com>"
 ]
-license = "MIT/Apache-2.0"
-edition = "2021"
 categories = [
-    "no-std",
-    "no-std::no-alloc",
-    "parsing",
+  "no-std",
+  "no-std::no-alloc",
+  "parsing",
 ]
 keywords = [
-    "Multiboot2",
-    "kernel",
-    "boot",
-    "bootloader",
+  "Multiboot2",
+  "kernel",
+  "boot",
+  "bootloader",
 ]
 # without this, sometimes crates.io doesn't show the preview of the README
 # I expeciended this multiple times in the past
@@ -32,21 +30,21 @@ readme = "README.md"
 homepage = "https://github.com/rust-osdev/multiboot2/tree/main/multiboot2"
 repository = "https://github.com/rust-osdev/multiboot2"
 documentation = "https://docs.rs/multiboot2"
-rust-version = "1.75"
+edition.workspace = true
+license.workspace = true
+rust-version.workspace = true
 
 [features]
 default = ["builder"]
 alloc = ["multiboot2-common/alloc"]
 builder = ["alloc", "multiboot2-common/builder"]
-# Nightly-only features, which will eventually be stabilized.
-unstable = ["multiboot2-common/unstable"]
 
 [dependencies]
 bitflags.workspace = true
-derive_more.workspace = true
 log.workspace = true
-ptr_meta.workspace = true
 multiboot2-common.workspace = true
+ptr_meta.workspace = true
+thiserror.workspace = true
 uefi-raw = { version = "~0.8.0", default-features = false }
 
 [package.metadata.docs.rs]
diff --git a/multiboot2/README.md b/multiboot2/README.md
index efd4694f..de49d1af 100644
--- a/multiboot2/README.md
+++ b/multiboot2/README.md
@@ -47,7 +47,7 @@ There are many different types of tags, but they all have the same beginning:
 
 ## MSRV
 
-The MSRV is 1.75.0 stable.
+The MSRV is 1.85.0 stable.
 
 ## License & Contribution
 
diff --git a/multiboot2/src/boot_information.rs b/multiboot2/src/boot_information.rs
index 1204e1f6..ba4f0fb5 100644
--- a/multiboot2/src/boot_information.rs
+++ b/multiboot2/src/boot_information.rs
@@ -3,41 +3,31 @@
 use crate::framebuffer::UnknownFramebufferType;
 use crate::tag::TagHeader;
 use crate::{
-    module, ApmTag, BasicMemoryInfoTag, BootLoaderNameTag, BootdevTag, CommandLineTag,
+    ApmTag, BasicMemoryInfoTag, BootLoaderNameTag, BootdevTag, CommandLineTag,
     EFIBootServicesNotExitedTag, EFIImageHandle32Tag, EFIImageHandle64Tag, EFIMemoryMapTag,
     EFISdt32Tag, EFISdt64Tag, ElfSectionIter, ElfSectionsTag, EndTag, FramebufferTag,
     ImageLoadPhysAddrTag, MemoryMapTag, ModuleIter, NetworkTag, RsdpV1Tag, RsdpV2Tag, SmbiosTag,
-    TagIter, TagType, VBEInfoTag,
+    TagIter, TagType, VBEInfoTag, module,
 };
-#[cfg(feature = "unstable")]
-use core::error::Error;
 use core::fmt;
 use core::mem;
 use core::ptr::NonNull;
-use derive_more::Display;
 use multiboot2_common::{DynSizedStructure, Header, MaybeDynSized, MemoryError, Tag};
+use thiserror::Error;
 
 /// Errors that occur when a chunk of memory can't be parsed as
 /// [`BootInformation`].
-#[derive(Display, Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Error)]
 pub enum LoadError {
     /// The provided memory can't be parsed as [`BootInformation`].
     /// See [`MemoryError`].
-    Memory(MemoryError),
+    #[error("memory can't be parsed as boot information")]
+    Memory(#[source] MemoryError),
     /// Missing mandatory end tag.
+    #[error("missing mandatory end tag")]
     NoEndTag,
 }
 
-#[cfg(feature = "unstable")]
-impl Error for LoadError {
-    fn source(&self) -> Option<&(dyn Error + 'static)> {
-        match self {
-            Self::Memory(inner) => Some(inner),
-            Self::NoEndTag => None,
-        }
-    }
-}
-
 /// The basic header of a [`BootInformation`] as sized Rust type.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[repr(C, align(8))]
@@ -104,7 +94,7 @@ impl<'a> BootInformation<'a> {
     ///   program may observe unsynchronized mutation.
     pub unsafe fn load(ptr: *const BootInformationHeader) -> Result<Self, LoadError> {
         let ptr = NonNull::new(ptr.cast_mut()).ok_or(LoadError::Memory(MemoryError::Null))?;
-        let inner = DynSizedStructure::ref_from_ptr(ptr).map_err(LoadError::Memory)?;
+        let inner = unsafe { DynSizedStructure::ref_from_ptr(ptr).map_err(LoadError::Memory)? };
 
         let this = Self(inner);
         if !this.has_valid_end_tag() {
diff --git a/multiboot2/src/boot_loader_name.rs b/multiboot2/src/boot_loader_name.rs
index 1b4e45dd..636bd97d 100644
--- a/multiboot2/src/boot_loader_name.rs
+++ b/multiboot2/src/boot_loader_name.rs
@@ -1,7 +1,7 @@
 //! Module for [`BootLoaderNameTag`].
 
 use crate::tag::TagHeader;
-use crate::{parse_slice_as_string, StringError, TagType};
+use crate::{StringError, TagType, parse_slice_as_string};
 use core::fmt::{Debug, Formatter};
 use core::mem;
 use multiboot2_common::{MaybeDynSized, Tag};
diff --git a/multiboot2/src/builder.rs b/multiboot2/src/builder.rs
index 872fe08c..834b57a5 100644
--- a/multiboot2/src/builder.rs
+++ b/multiboot2/src/builder.rs
@@ -11,7 +11,7 @@ use crate::{
 };
 use alloc::boxed::Box;
 use alloc::vec::Vec;
-use multiboot2_common::{new_boxed, DynSizedStructure, MaybeDynSized};
+use multiboot2_common::{DynSizedStructure, MaybeDynSized, new_boxed};
 
 /// Builder for a Multiboot2 header information.
 // #[derive(Debug)]
diff --git a/multiboot2/src/command_line.rs b/multiboot2/src/command_line.rs
index d3cd4b4e..405cfb25 100644
--- a/multiboot2/src/command_line.rs
+++ b/multiboot2/src/command_line.rs
@@ -1,7 +1,7 @@
 //! Module for [`CommandLineTag`].
 
 use crate::tag::TagHeader;
-use crate::{parse_slice_as_string, StringError, TagType};
+use crate::{StringError, TagType, parse_slice_as_string};
 use core::fmt::{Debug, Formatter};
 use core::mem;
 use core::str;
diff --git a/multiboot2/src/efi.rs b/multiboot2/src/efi.rs
index a7f2aad7..a3a14093 100644
--- a/multiboot2/src/efi.rs
+++ b/multiboot2/src/efi.rs
@@ -6,8 +6,8 @@
 //! - [`EFIImageHandle64Tag`]
 //! - [`EFIBootServicesNotExitedTag`]
 
-use crate::tag::TagHeader;
 use crate::TagType;
+use crate::tag::TagHeader;
 use core::mem::size_of;
 use multiboot2_common::{MaybeDynSized, Tag};
 
diff --git a/multiboot2/src/elf_sections.rs b/multiboot2/src/elf_sections.rs
index b2cc2499..a084cb4c 100644
--- a/multiboot2/src/elf_sections.rs
+++ b/multiboot2/src/elf_sections.rs
@@ -219,7 +219,7 @@ struct ElfSectionInner64 {
 }
 
 impl ElfSection<'_> {
-    /// Get the section type as a `ElfSectionType` enum variant.
+    /// Get the section type as an `ElfSectionType` enum variant.
     #[must_use]
     pub fn section_type(&self) -> ElfSectionType {
         match self.get().typ() {
@@ -238,10 +238,7 @@ impl ElfSection<'_> {
             0x6000_0000..=0x6FFF_FFFF => ElfSectionType::EnvironmentSpecific,
             0x7000_0000..=0x7FFF_FFFF => ElfSectionType::ProcessorSpecific,
             e => {
-                log::warn!(
-                    "Unknown section type {:x}. Treating as ElfSectionType::Unused",
-                    e
-                );
+                log::warn!("Unknown section type {e:x}. Treating as ElfSectionType::Unused");
                 ElfSectionType::Unused
             }
         }
@@ -318,17 +315,24 @@ impl ElfSection<'_> {
         match self.entry_size {
             40 => unsafe { &*(self.inner as *const ElfSectionInner32) },
             64 => unsafe { &*(self.inner as *const ElfSectionInner64) },
-            s => panic!("Unexpected entry size: {}", s),
+            s => panic!("Unexpected entry size: {s}"),
         }
     }
 
     unsafe fn string_table(&self) -> *const u8 {
-        let addr = match self.entry_size {
-            40 => (*(self.string_section as *const ElfSectionInner32)).addr as usize,
-            64 => (*(self.string_section as *const ElfSectionInner64)).addr as usize,
-            s => panic!("Unexpected entry size: {}", s),
-        };
-        addr as *const _
+        match self.entry_size {
+            40 => {
+                let ptr = self.string_section.cast::<ElfSectionInner32>();
+                let reference = unsafe { ptr.as_ref().unwrap() };
+                reference.addr() as *const u8
+            }
+            64 => {
+                let ptr = self.string_section.cast::<ElfSectionInner64>();
+                let reference = unsafe { ptr.as_ref().unwrap() };
+                reference.addr() as *const u8
+            }
+            s => panic!("Unexpected entry size: {s}"),
+        }
     }
 }
 
diff --git a/multiboot2/src/framebuffer.rs b/multiboot2/src/framebuffer.rs
index c8ab7b75..8151dccf 100644
--- a/multiboot2/src/framebuffer.rs
+++ b/multiboot2/src/framebuffer.rs
@@ -1,12 +1,12 @@
 //! Module for [`FramebufferTag`].
 
-use crate::tag::TagHeader;
 use crate::TagType;
+use crate::tag::TagHeader;
 use core::fmt::Debug;
 use core::mem;
 use core::slice;
-use derive_more::Display;
 use multiboot2_common::{MaybeDynSized, Tag};
+use thiserror::Error;
 #[cfg(feature = "builder")]
 use {alloc::boxed::Box, multiboot2_common::new_boxed};
 
@@ -402,13 +402,10 @@ pub struct FramebufferColor {
 }
 
 /// Error when an unknown [`FramebufferTypeId`] is found.
-#[derive(Debug, Copy, Clone, Display, PartialEq, Eq)]
-#[display("Unknown framebuffer type {}", _0)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Error)]
+#[error("Unknown framebuffer type {0}")]
 pub struct UnknownFramebufferType(u8);
 
-#[cfg(feature = "unstable")]
-impl core::error::Error for UnknownFramebufferType {}
-
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/multiboot2/src/image_load_addr.rs b/multiboot2/src/image_load_addr.rs
index bb4913d0..560671a1 100644
--- a/multiboot2/src/image_load_addr.rs
+++ b/multiboot2/src/image_load_addr.rs
@@ -1,7 +1,7 @@
 //! Module for [`ImageLoadPhysAddrTag`].
 
-use crate::tag::TagHeader;
 use crate::TagType;
+use crate::tag::TagHeader;
 #[cfg(feature = "builder")]
 use core::mem::size_of;
 use multiboot2_common::{MaybeDynSized, Tag};
diff --git a/multiboot2/src/lib.rs b/multiboot2/src/lib.rs
index a5b443d4..69d3a85b 100644
--- a/multiboot2/src/lib.rs
+++ b/multiboot2/src/lib.rs
@@ -1,5 +1,4 @@
 #![no_std]
-#![cfg_attr(feature = "unstable", feature(error_in_core))]
 // --- BEGIN STYLE CHECKS ---
 #![deny(
     clippy::all,
@@ -42,7 +41,7 @@
 //! ```
 //!
 //! ## MSRV
-//! The MSRV is 1.75.0 stable.
+//! The MSRV is 1.85.0 stable.
 
 #[cfg_attr(feature = "builder", macro_use)]
 #[cfg(feature = "builder")]
@@ -115,7 +114,7 @@ pub use rsdp::{RsdpV1Tag, RsdpV2Tag};
 pub use smbios::SmbiosTag;
 pub use tag::TagHeader;
 pub use tag_type::{TagType, TagTypeId};
-pub use util::{parse_slice_as_string, StringError};
+pub use util::{StringError, parse_slice_as_string};
 pub use vbe_info::{
     VBECapabilities, VBEControlInfo, VBEDirectColorAttributes, VBEField, VBEInfoTag,
     VBEMemoryModel, VBEModeAttributes, VBEModeInfo, VBEWindowAttributes,
@@ -1102,7 +1101,6 @@ mod tests {
     }
 
     #[test]
-    #[cfg(feature = "unstable")]
     /// This test succeeds if it compiles.
     fn mbi_load_error_implements_error() {
         fn consumer<E: core::error::Error>(_e: E) {}
diff --git a/multiboot2/src/memory_map.rs b/multiboot2/src/memory_map.rs
index 2d633fd4..07422984 100644
--- a/multiboot2/src/memory_map.rs
+++ b/multiboot2/src/memory_map.rs
@@ -422,7 +422,11 @@ impl<'a> EFIMemoryAreaIter<'a> {
     fn new(mmap_tag: &'a EFIMemoryMapTag) -> Self {
         let desc_size = mmap_tag.desc_size as usize;
         let mmap_len = mmap_tag.memory_map.len();
-        assert_eq!(mmap_len % desc_size, 0, "memory map length must be a multiple of `desc_size` by definition. The MBI seems to be corrupt.");
+        assert_eq!(
+            mmap_len % desc_size,
+            0,
+            "memory map length must be a multiple of `desc_size` by definition. The MBI seems to be corrupt."
+        );
         Self {
             mmap_tag,
             i: 0,
diff --git a/multiboot2/src/module.rs b/multiboot2/src/module.rs
index aa7e30d4..d87ab6f9 100644
--- a/multiboot2/src/module.rs
+++ b/multiboot2/src/module.rs
@@ -1,7 +1,7 @@
 //! Module for [`ModuleTag`].
 
 use crate::tag::TagHeader;
-use crate::{parse_slice_as_string, StringError, TagIter, TagType};
+use crate::{StringError, TagIter, TagType, parse_slice_as_string};
 use core::fmt::{Debug, Formatter};
 use core::mem;
 use multiboot2_common::{MaybeDynSized, Tag};
diff --git a/multiboot2/src/rsdp.rs b/multiboot2/src/rsdp.rs
index fbc88005..bd86ec18 100644
--- a/multiboot2/src/rsdp.rs
+++ b/multiboot2/src/rsdp.rs
@@ -12,8 +12,8 @@
 //! signature should be manually verified.
 //!
 
-use crate::tag::TagHeader;
 use crate::TagType;
+use crate::tag::TagHeader;
 #[cfg(feature = "builder")]
 use core::mem::size_of;
 use core::slice;
diff --git a/multiboot2/src/smbios.rs b/multiboot2/src/smbios.rs
index 0d80b0b0..0eef33d8 100644
--- a/multiboot2/src/smbios.rs
+++ b/multiboot2/src/smbios.rs
@@ -1,7 +1,7 @@
 //! Module for [`SmbiosTag`].
 
-use crate::tag::TagHeader;
 use crate::TagType;
+use crate::tag::TagHeader;
 use core::fmt::Debug;
 use core::mem;
 use multiboot2_common::{MaybeDynSized, Tag};
diff --git a/multiboot2/src/tag_type.rs b/multiboot2/src/tag_type.rs
index 3d5921c4..6ad4c334 100644
--- a/multiboot2/src/tag_type.rs
+++ b/multiboot2/src/tag_type.rs
@@ -305,7 +305,7 @@ mod tests {
         set.insert(TagType::LoadBaseAddr);
         set.insert(TagType::LoadBaseAddr);
         assert_eq!(set.len(), 4);
-        println!("{:#?}", set);
+        println!("{set:#?}");
     }
 
     #[test]
@@ -320,7 +320,7 @@ mod tests {
         for (current, next) in set.iter().zip(set.iter().skip(1)) {
             assert!(current < next);
         }
-        println!("{:#?}", set);
+        println!("{set:#?}");
     }
 
     /// Tests for equality when one type is u32 and the other the enum representation.
diff --git a/multiboot2/src/util.rs b/multiboot2/src/util.rs
index 33939075..f6f6787c 100644
--- a/multiboot2/src/util.rs
+++ b/multiboot2/src/util.rs
@@ -1,33 +1,18 @@
 //! Various utilities.
 
-use core::fmt;
-use core::fmt::{Display, Formatter};
 use core::str::Utf8Error;
+use thiserror::Error;
 
 /// Error type describing failures when parsing the string from a tag.
-#[derive(Debug, PartialEq, Eq, Clone)]
+#[derive(Debug, PartialEq, Eq, Clone, Error)]
 pub enum StringError {
     /// There is no terminating NUL character, although the specification
     /// requires one.
-    MissingNul(core::ffi::FromBytesUntilNulError),
+    #[error("string is not null terminated")]
+    MissingNul(#[source] core::ffi::FromBytesUntilNulError),
     /// The sequence until the first NUL character is not valid UTF-8.
-    Utf8(Utf8Error),
-}
-
-impl Display for StringError {
-    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        write!(f, "{:?}", self)
-    }
-}
-
-#[cfg(feature = "unstable")]
-impl core::error::Error for StringError {
-    fn source(&self) -> Option<&(dyn core::error::Error + 'static)> {
-        match self {
-            Self::MissingNul(e) => Some(e),
-            Self::Utf8(e) => Some(e),
-        }
-    }
+    #[error("string is not valid UTF-8")]
+    Utf8(#[source] Utf8Error),
 }
 
 /// Parses the provided byte sequence as Multiboot string, which maps to a
diff --git a/nix/sources.json b/nix/sources.json
deleted file mode 100644
index 5da91e3a..00000000
--- a/nix/sources.json
+++ /dev/null
@@ -1,14 +0,0 @@
-{
-    "nixpkgs": {
-        "branch": "nixos-23.11",
-        "description": "Nix Packages collection",
-        "homepage": null,
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "576ecd43d3b864966b4423a853412d6177775e8b",
-        "sha256": "05gr8w09w7fqfi6zflx7df1n0hhsf8f4p9siikk3wb7k7by2d9sr",
-        "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/576ecd43d3b864966b4423a853412d6177775e8b.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    }
-}
diff --git a/nix/sources.nix b/nix/sources.nix
deleted file mode 100644
index fe3dadf7..00000000
--- a/nix/sources.nix
+++ /dev/null
@@ -1,198 +0,0 @@
-# This file has been generated by Niv.
-
-let
-
-  #
-  # The fetchers. fetch_<type> fetches specs of type <type>.
-  #
-
-  fetch_file = pkgs: name: spec:
-    let
-      name' = sanitizeName name + "-src";
-    in
-    if spec.builtin or true then
-      builtins_fetchurl { inherit (spec) url sha256; name = name'; }
-    else
-      pkgs.fetchurl { inherit (spec) url sha256; name = name'; };
-
-  fetch_tarball = pkgs: name: spec:
-    let
-      name' = sanitizeName name + "-src";
-    in
-    if spec.builtin or true then
-      builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
-    else
-      pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
-
-  fetch_git = name: spec:
-    let
-      ref =
-        spec.ref or (
-          if spec ? branch then "refs/heads/${spec.branch}" else
-          if spec ? tag then "refs/tags/${spec.tag}" else
-          abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!"
-        );
-      submodules = spec.submodules or false;
-      submoduleArg =
-        let
-          nixSupportsSubmodules = builtins.compareVersions builtins.nixVersion "2.4" >= 0;
-          emptyArgWithWarning =
-            if submodules
-            then
-              builtins.trace
-                (
-                  "The niv input \"${name}\" uses submodules "
-                  + "but your nix's (${builtins.nixVersion}) builtins.fetchGit "
-                  + "does not support them"
-                )
-                { }
-            else { };
-        in
-        if nixSupportsSubmodules
-        then { inherit submodules; }
-        else emptyArgWithWarning;
-    in
-    builtins.fetchGit
-      ({ url = spec.repo; inherit (spec) rev; inherit ref; } // submoduleArg);
-
-  fetch_local = spec: spec.path;
-
-  fetch_builtin-tarball = name: throw
-    ''[${name}] The niv type "builtin-tarball" is deprecated. You should instead use `builtin = true`.
-        $ niv modify ${name} -a type=tarball -a builtin=true'';
-
-  fetch_builtin-url = name: throw
-    ''[${name}] The niv type "builtin-url" will soon be deprecated. You should instead use `builtin = true`.
-        $ niv modify ${name} -a type=file -a builtin=true'';
-
-  #
-  # Various helpers
-  #
-
-  # https://github.com/NixOS/nixpkgs/pull/83241/files#diff-c6f540a4f3bfa4b0e8b6bafd4cd54e8bR695
-  sanitizeName = name:
-    (
-      concatMapStrings (s: if builtins.isList s then "-" else s)
-        (
-          builtins.split "[^[:alnum:]+._?=-]+"
-            ((x: builtins.elemAt (builtins.match "\\.*(.*)" x) 0) name)
-        )
-    );
-
-  # The set of packages used when specs are fetched using non-builtins.
-  mkPkgs = sources: system:
-    let
-      sourcesNixpkgs =
-        import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) { inherit system; };
-      hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath;
-      hasThisAsNixpkgsPath = <nixpkgs> == ./.;
-    in
-    if builtins.hasAttr "nixpkgs" sources
-    then sourcesNixpkgs
-    else if hasNixpkgsPath && ! hasThisAsNixpkgsPath then
-      import <nixpkgs> { }
-    else
-      abort
-        ''
-          Please specify either <nixpkgs> (through -I or NIX_PATH=nixpkgs=...) or
-          add a package called "nixpkgs" to your sources.json.
-        '';
-
-  # The actual fetching function.
-  fetch = pkgs: name: spec:
-
-    if ! builtins.hasAttr "type" spec then
-      abort "ERROR: niv spec ${name} does not have a 'type' attribute"
-    else if spec.type == "file" then fetch_file pkgs name spec
-    else if spec.type == "tarball" then fetch_tarball pkgs name spec
-    else if spec.type == "git" then fetch_git name spec
-    else if spec.type == "local" then fetch_local spec
-    else if spec.type == "builtin-tarball" then fetch_builtin-tarball name
-    else if spec.type == "builtin-url" then fetch_builtin-url name
-    else
-      abort "ERROR: niv spec ${name} has unknown type ${builtins.toJSON spec.type}";
-
-  # If the environment variable NIV_OVERRIDE_${name} is set, then use
-  # the path directly as opposed to the fetched source.
-  replace = name: drv:
-    let
-      saneName = stringAsChars (c: if (builtins.match "[a-zA-Z0-9]" c) == null then "_" else c) name;
-      ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}";
-    in
-    if ersatz == "" then drv else
-      # this turns the string into an actual Nix path (for both absolute and
-      # relative paths)
-    if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}";
-
-  # Ports of functions for older nix versions
-
-  # a Nix version of mapAttrs if the built-in doesn't exist
-  mapAttrs = builtins.mapAttrs or (
-    f: set: with builtins;
-    listToAttrs (map (attr: { name = attr; value = f attr set.${attr}; }) (attrNames set))
-  );
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/lists.nix#L295
-  range = first: last: if first > last then [ ] else builtins.genList (n: first + n) (last - first + 1);
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L257
-  stringToCharacters = s: map (p: builtins.substring p 1 s) (range 0 (builtins.stringLength s - 1));
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L269
-  stringAsChars = f: s: concatStrings (map f (stringToCharacters s));
-  concatMapStrings = f: list: concatStrings (map f list);
-  concatStrings = builtins.concatStringsSep "";
-
-  # https://github.com/NixOS/nixpkgs/blob/8a9f58a375c401b96da862d969f66429def1d118/lib/attrsets.nix#L331
-  optionalAttrs = cond: as: if cond then as else { };
-
-  # fetchTarball version that is compatible between all the versions of Nix
-  builtins_fetchTarball = { url, name ? null, sha256 }@attrs:
-    let
-      inherit (builtins) lessThan nixVersion fetchTarball;
-    in
-    if lessThan nixVersion "1.12" then
-      fetchTarball ({ inherit url; } // (optionalAttrs (name != null) { inherit name; }))
-    else
-      fetchTarball attrs;
-
-  # fetchurl version that is compatible between all the versions of Nix
-  builtins_fetchurl = { url, name ? null, sha256 }@attrs:
-    let
-      inherit (builtins) lessThan nixVersion fetchurl;
-    in
-    if lessThan nixVersion "1.12" then
-      fetchurl ({ inherit url; } // (optionalAttrs (name != null) { inherit name; }))
-    else
-      fetchurl attrs;
-
-  # Create the final "sources" from the config
-  mkSources = config:
-    mapAttrs
-      (
-        name: spec:
-          if builtins.hasAttr "outPath" spec
-          then
-            abort
-              "The values in sources.json should not have an 'outPath' attribute"
-          else
-            spec // { outPath = replace name (fetch config.pkgs name spec); }
-      )
-      config.sources;
-
-  # The "config" used by the fetchers
-  mkConfig =
-    { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null
-    , sources ? if sourcesFile == null then { } else builtins.fromJSON (builtins.readFile sourcesFile)
-    , system ? builtins.currentSystem
-    , pkgs ? mkPkgs sources system
-    }: rec {
-      # The sources, i.e. the attribute set of spec name to spec
-      inherit sources;
-
-      # The "pkgs" (evaluated nixpkgs) to use for e.g. non-builtin fetchers
-      inherit pkgs;
-    };
-
-in
-mkSources (mkConfig { }) // { __functor = _: settings: mkSources (mkConfig settings); }
diff --git a/shell.nix b/shell.nix
index 178c58af..3a03c743 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,7 +1,5 @@
-let
-  sources = import ./nix/sources.nix;
-  pkgs = import sources.nixpkgs {};
-in
+{ pkgs ? import <nixpkgs> {} }:
+
 pkgs.mkShell rec {
   packages = with pkgs; [
     # general
@@ -18,9 +16,4 @@ pkgs.mkShell rec {
     ./integration-test/run.sh
     '')
   ];
-
-  # To invoke "nix-shell" in the CI-runner, we need a global Nix channel.
-  # For better reproducibility inside the Nix shell, we override this channel
-  # with the pinned nixpkgs version.
-  NIX_PATH = "nixpkgs=${sources.nixpkgs}";
 }