2 files changed, 17 insertions, 18 deletions
diff --git a/third_party/nix/src/libstore/build.cc b/third_party/nix/src/libstore/build.cc
index a9d40991d30d..91f80e51e042 100644
--- a/third_party/nix/src/libstore/build.cc
+++ b/third_party/nix/src/libstore/build.cc
@@ -96,21 +96,21 @@ struct CompareGoalPtrs {
 };
 
 /* Set of goals. */
-typedef std::set<GoalPtr, CompareGoalPtrs> Goals;
+using Goals = std::set<GoalPtr, CompareGoalPtrs>;
 using WeakGoals = std::list<WeakGoalPtr>;
 
 /* A map of paths to goals (and the other way around). */
-typedef std::map<Path, WeakGoalPtr> WeakGoalMap;
+using WeakGoalMap = std::map<Path, WeakGoalPtr>;
 
 class Goal : public std::enable_shared_from_this<Goal> {
  public:
-  typedef enum {
+  using ExitCode = enum {
     ecBusy,
     ecSuccess,
     ecFailed,
     ecNoSubstituters,
     ecIncompleteClosure
-  } ExitCode;
+  };
 
  protected:
   /* Backlink to the worker. */
@@ -728,7 +728,7 @@ std::string rewriteStrings(std::string s, const StringRewrites& rewrites) {
 
 //////////////////////////////////////////////////////////////////////
 
-typedef enum { rpAccept, rpDecline, rpPostpone } HookReply;
+using HookReply = enum { rpAccept, rpDecline, rpPostpone };
 
 class SubstitutionGoal;
 
@@ -835,16 +835,16 @@ class DerivationGoal : public Goal {
     explicit ChrootPath(Path source = "", bool optional = false)
         : source(std::move(source)), optional(optional) {}
   };
-  typedef std::map<Path, ChrootPath>
-      DirsInChroot;  // maps target path to source path
+  using DirsInChroot =
+      std::map<Path, ChrootPath>;  // maps target path to source path
   DirsInChroot dirsInChroot;
 
-  typedef std::map<std::string, std::string> Environment;
+  using Environment = std::map<std::string, std::string>;
   Environment env;
 
   /* Hash rewriting. */
   StringRewrites inputRewrites, outputRewrites;
-  typedef std::map<Path, Path> RedirectedOutputs;
+  using RedirectedOutputs = std::map<Path, Path>;
   RedirectedOutputs redirectedOutputs;
 
   BuildMode buildMode;
diff --git a/third_party/nix/src/libstore/store-api.hh b/third_party/nix/src/libstore/store-api.hh
index bb2f1a950bfd..6c125ad2765f 100644
--- a/third_party/nix/src/libstore/store-api.hh
+++ b/third_party/nix/src/libstore/store-api.hh
@@ -50,7 +50,7 @@ const size_t storePathHashLen = 32;  // i.e. 160 bits
 /* Magic header of exportPath() output (obsolete). */
 const uint32_t exportMagic = 0x4558494e;
 
-typedef std::unordered_map<Path, std::unordered_set<std::string>> Roots;
+using Roots = std::unordered_map<Path, std::unordered_set<std::string>>;
 
 struct GCOptions {
   /* Garbage collector operation:
@@ -66,12 +66,12 @@ struct GCOptions {
      - `gcDeleteSpecific': delete the paths listed in
         `pathsToDelete', insofar as they are not reachable.
   */
-  typedef enum {
+  using GCAction = enum {
     gcReturnLive,
     gcReturnDead,
     gcDeleteDead,
     gcDeleteSpecific,
-  } GCAction;
+  };
 
   GCAction action{gcDeleteDead};
 
@@ -110,7 +110,7 @@ struct SubstitutablePathInfo {
   unsigned long long narSize;      /* 0 = unknown */
 };
 
-typedef std::map<Path, SubstitutablePathInfo> SubstitutablePathInfos;
+using SubstitutablePathInfos = std::map<Path, SubstitutablePathInfo>;
 
 struct ValidPathInfo {
   Path path;
@@ -248,7 +248,7 @@ struct BuildResult {
 
 class Store : public std::enable_shared_from_this<Store>, public Config {
  public:
-  typedef std::map<std::string, std::string> Params;
+  using Params = std::map<std::string, std::string>;
 
   const PathSetting storeDir_{this, false, settings.nixStore, "store",
                               "path to the Nix store"};
@@ -780,12 +780,11 @@ StoreType getStoreType(const std::string& uri = settings.storeUri.get(),
 std::list<ref<Store>> getDefaultSubstituters();
 
 /* Store implementation registration. */
-typedef std::function<std::shared_ptr<Store>(const std::string& uri,
-                                             const Store::Params& params)>
-    OpenStore;
+using OpenStore = std::function<std::shared_ptr<Store>(const std::string&,
+                                                       const Store::Params&)>;
 
 struct RegisterStoreImplementation {
-  typedef std::vector<OpenStore> Implementations;
+  using Implementations = std::vector<OpenStore>;
   static Implementations* implementations;
 
   RegisterStoreImplementation(OpenStore fun) {