diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 71a511c41..4d5aaf86a 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -724,9 +724,12 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * *
 
         auto outPath = state.store->makeFixedOutputPath(outputHashRecursive, h, drvName);
         if (!jsonObject) drv.env["out"] = state.store->printStorePath(outPath);
-        drv.outputs.insert_or_assign("out", DerivationOutput(std::move(outPath),
-                (static_cast<bool>(outputHashRecursive) ? "r:" : "") + printHashType(h.type),
-                h.to_string(Base16, false)));
+        drv.outputs.insert_or_assign("out", DerivationOutput {
+            std::move(outPath),
+            (outputHashRecursive == FileIngestionMethod::Recursive ? "r:" : "")
+                + printHashType(h.type),
+            h.to_string(Base16, false),
+        });
     }
 
     else {
diff --git a/src/libstore/build.cc b/src/libstore/build.cc
index 224633106..be52e637e 100644
--- a/src/libstore/build.cc
+++ b/src/libstore/build.cc
@@ -3650,7 +3650,7 @@ void DerivationGoal::registerOutputs()
             FileIngestionMethod recursive; Hash h;
             i.second.parseHashInfo(recursive, h);
 
-            if (!static_cast<bool>(recursive)) {
+            if (recursive == FileIngestionMethod::Flat) {
                 /* The output path should be a regular file without execute permission. */
                 if (!S_ISREG(st.st_mode) || (st.st_mode & S_IXUSR) != 0)
                     throw BuildError(
@@ -3659,7 +3659,9 @@ void DerivationGoal::registerOutputs()
 
             /* Check the hash. In hash mode, move the path produced by
                the derivation to its content-addressed location. */
-            Hash h2 = static_cast<bool>(recursive) ? hashPath(h.type, actualPath).first : hashFile(h.type, actualPath);
+            Hash h2 = recursive == FileIngestionMethod::Recursive
+                ? hashPath(h.type, actualPath).first
+                : hashFile(h.type, actualPath);
 
             auto dest = worker.store.makeFixedOutputPath(recursive, h2, i.second.path.name());
 
@@ -3912,7 +3914,9 @@ void DerivationGoal::checkOutputs(const std::map<Path, ValidPathInfo> & outputs)
 
                 auto spec = parseReferenceSpecifiers(worker.store, *drv, *value);
 
-                auto used = static_cast<bool>(recursive) ? cloneStorePathSet(getClosure(info.path).first) : cloneStorePathSet(info.references);
+                auto used = recursive
+                    ? cloneStorePathSet(getClosure(info.path).first)
+                    : cloneStorePathSet(info.references);
 
                 if (recursive && checks.ignoreSelfRefs)
                     used.erase(info.path);
diff --git a/src/libstore/path.hh b/src/libstore/path.hh
index 73c4b8e29..5122e7422 100644
--- a/src/libstore/path.hh
+++ b/src/libstore/path.hh
@@ -73,7 +73,7 @@ const size_t storePathHashLen = 32; // i.e. 160 bits
 /* Extension of derivations in the Nix store. */
 const std::string drvExtension = ".drv";
 
-enum struct FileIngestionMethod : bool {
+enum struct FileIngestionMethod : uint8_t {
     Flat = false,
     Recursive = true
 };
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index 06aa0883c..ca1409588 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -177,13 +177,16 @@ StorePath Store::makeFixedOutputPath(
     const StorePathSet & references,
     bool hasSelfReference) const
 {
-    if (hash.type == htSHA256  && recursive == FileIngestionMethod::Recursive) {
+    if (hash.type == htSHA256 && recursive == FileIngestionMethod::Recursive) {
         return makeStorePath(makeType(*this, "source", references, hasSelfReference), hash, name);
     } else {
         assert(references.empty());
-        return makeStorePath("output:out", hashString(htSHA256,
-                "fixed:out:" + (static_cast<bool>(recursive) ? (string) "r:" : "") +
-                hash.to_string(Base16) + ":"), name);
+        return makeStorePath("output:out",
+            hashString(htSHA256,
+                "fixed:out:"
+                + (recursive == FileIngestionMethod::Recursive ? (string) "r:" : "")
+                + hash.to_string(Base16) + ":"),
+            name);
     }
 }
 
@@ -202,7 +205,9 @@ StorePath Store::makeTextPath(std::string_view name, const Hash & hash,
 std::pair<StorePath, Hash> Store::computeStorePathForPath(std::string_view name,
     const Path & srcPath, FileIngestionMethod recursive, HashType hashAlgo, PathFilter & filter) const
 {
-    Hash h = static_cast<bool>(recursive) ? hashPath(hashAlgo, srcPath, filter).first : hashFile(hashAlgo, srcPath);
+    Hash h = recursive == FileIngestionMethod::Recursive
+        ? hashPath(hashAlgo, srcPath, filter).first
+        : hashFile(hashAlgo, srcPath);
     return std::make_pair(makeFixedOutputPath(recursive, h, name), h);
 }
 
@@ -782,7 +787,7 @@ bool ValidPathInfo::isContentAddressed(const Store & store) const
 
     else if (hasPrefix(ca, "fixed:")) {
         FileIngestionMethod recursive { ca.compare(6, 2, "r:") == 0 };
-        Hash hash(std::string(ca, static_cast<bool>(recursive) ? 8 : 6));
+        Hash hash(std::string(ca, recursive == FileIngestionMethod::Recursive ? 8 : 6));
         auto refs = cloneStorePathSet(references);
         bool hasSelfReference = false;
         if (refs.count(path)) {
@@ -828,7 +833,9 @@ Strings ValidPathInfo::shortRefs() const
 
 std::string makeFixedOutputCA(FileIngestionMethod recursive, const Hash & hash)
 {
-    return "fixed:" + (static_cast<bool>(recursive) ? (std::string) "r:" : "") + hash.to_string();
+    return "fixed:"
+        + (recursive == FileIngestionMethod::Recursive ? (std::string) "r:" : "")
+        + hash.to_string();
 }