diff --git a/flake.lock b/flake.lock
index 3ba015ba6f7..c40f8135caf 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,12 +2,12 @@
   "nodes": {
     "flake-compat": {
       "locked": {
-        "lastModified": 1696426674,
-        "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
-        "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
-        "revCount": 57,
+        "lastModified": 1733328505,
+        "narHash": "sha256-NeCCThCEP3eCl2l/+27kNNK7QrwZB1IJCrXfrbv5oqU=",
+        "rev": "ff81ac966bb2cae68946d5ed5fc4994f96d0ffec",
+        "revCount": 69,
         "type": "tarball",
-        "url": "https://api.flakehub.com/f/pinned/edolstra/flake-compat/1.0.1/018afb31-abd1-7bff-a5e4-cff7e18efb7a/source.tar.gz"
+        "url": "https://api.flakehub.com/f/pinned/edolstra/flake-compat/1.1.0/01948eb7-9cba-704f-bbf3-3fa956735b52/source.tar.gz"
       },
       "original": {
         "type": "tarball",
@@ -19,11 +19,11 @@
         "systems": "systems"
       },
       "locked": {
-        "lastModified": 1726560853,
-        "narHash": "sha256-X6rJYSESBVr3hBoH0WbKE5KvhPU5bloyZ2L4K60/fPQ=",
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "c1dfcf08411b08f6b8615f7d8971a2bfa81d5e8a",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
         "type": "github"
       },
       "original": {
@@ -34,16 +34,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1729076285,
-        "narHash": "sha256-0pKZR4g2X3YTOcLQexuDrN2vIdFQJ1djqXSBfD0gEgE=",
+        "lastModified": 1742305402,
+        "narHash": "sha256-56UcjoVVkB7rAbiY9Y79Th4pOlx0e1hv6Cfny8rlP8U=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "2a3b139da1ffe0cdd6ab82583e147a75738ba4f8",
+        "rev": "6c8e4e4546146ddf05e9433ca560fa6260d00a14",
         "type": "github"
       },
       "original": {
         "owner": "nixos",
-        "ref": "master",
+        "ref": "release-24.11",
         "repo": "nixpkgs",
         "type": "github"
       }
diff --git a/flake.nix b/flake.nix
index f2517590275..33fa8f9ad2b 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,6 +1,6 @@
 {
   inputs = {
-    nixpkgs.url = "github:nixos/nixpkgs/master";
+    nixpkgs.url = "github:nixos/nixpkgs/release-24.11";
 
     # cross-platform convenience
     flake-utils.url = "github:numtide/flake-utils";
@@ -17,40 +17,67 @@
         pkgs = nixpkgs.legacyPackages.${system};
 
         # control versions
-        ruby = pkgs.ruby_3_3;
-        llvm = pkgs.llvmPackages_16;
-        gcc = pkgs.gcc13;
+        ruby = pkgs.ruby_3_4;
+        llvm = pkgs.llvmPackages_19;
+        gcc = pkgs.gcc14;
+
+        hook = ''
+          # get major.minor.0 ruby version
+          export RUBY_VERSION="$(ruby -e 'puts RUBY_VERSION.gsub(/\d+$/, "0")')"
+
+          # make gem install work in-project, compatibly with bundler
+          export GEM_HOME="$(pwd)/vendor/bundle/ruby/$RUBY_VERSION"
+
+          # make bundle work in-project
+          export BUNDLE_PATH="$(pwd)/vendor/bundle"
+
+          # enable calling gem scripts without bundle exec
+          export PATH="$GEM_HOME/bin:$PATH"
+
+          # enable implicitly resolving gems to bundled version
+          export RUBYGEMS_GEMDEPS="$(pwd)/Gemfile"
+        '';
+
+        deps = [
+          pkgs.libyaml.dev
+
+          # TODO: some gems insist on using `gcc` on Linux, satisfy them for now:
+          # - json
+          # - protobuf
+          # - ruby-prof
+          gcc
+        ];
       in {
-        devShell = pkgs.llvm.stdenv.mkDerivation {
+        devShells.default = llvm.stdenv.mkDerivation {
           name = "devshell";
 
-          buildInputs = with pkgs; [
-            ruby
-            libyaml.dev
+          buildInputs = [ ruby ] ++ deps;
 
-            # TODO: some gems insist on using `gcc` on Linux, satisfy them for now:
-            # - json
-            # - protobuf
-            # - ruby-prof
-            gcc
-          ];
+          shellHook = hook;
+        };
 
-          shellHook = ''
-            # get major.minor.0 ruby version
-            export RUBY_VERSION="$(ruby -e 'puts RUBY_VERSION.gsub(/\d+$/, "0")')"
+        devShells.ruby33 = llvm.stdenv.mkDerivation {
+          name = "devshell";
 
-            # make gem install work in-project, compatibly with bundler
-            export GEM_HOME="$(pwd)/vendor/bundle/ruby/$RUBY_VERSION"
+          buildInputs = [ pkgs.ruby_3_3 ] ++ deps;
 
-            # make bundle work in-project
-            export BUNDLE_PATH="$(pwd)/vendor/bundle"
+          shellHook = hook;
+        };
+
+        devShells.ruby32 = llvm.stdenv.mkDerivation {
+          name = "devshell";
+
+          buildInputs = [ pkgs.ruby_3_2 ] ++ deps;
+
+          shellHook = hook;
+        };
+
+        devShells.ruby31 = llvm.stdenv.mkDerivation {
+          name = "devshell";
 
-            # enable calling gem scripts without bundle exec
-            export PATH="$GEM_HOME/bin:$PATH"
+          buildInputs = [ pkgs.ruby_3_1 ] ++ deps;
 
-            # enable implicitly resolving gems to bundled version
-            export RUBYGEMS_GEMDEPS="$(pwd)/Gemfile"
-          '';
+          shellHook = hook;
         };
       }
     );
diff --git a/spec/datadog/tracing/contrib_spec.rb b/spec/datadog/tracing/contrib_spec.rb
index ec3f8f37ca3..e1a1f924f1d 100644
--- a/spec/datadog/tracing/contrib_spec.rb
+++ b/spec/datadog/tracing/contrib_spec.rb
@@ -1,7 +1,7 @@
 require 'spec_helper'
 
 RSpec.describe Datadog::Tracing::Contrib do
-  root = Gem::Specification.find_by_name('datadog').gem_dir
+  root = Gem.loaded_specs['datadog'].gem_dir
 
   # Our module names are camelized directory name with some exceptions
   mapping = {