diff --git a/.clang-tidy b/.clang-tidy
index cf9b74e1..0646e861 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -105,6 +105,10 @@ CheckOptions:
     value:           'NULL'
   - key:             performance-unnecessary-value-param.AllowedTypes
     value:           'absl::Status;absl::StatusOr;std::string_view'
+  - key:             readability-implicit-bool-conversion.AllowIntegerConditions
+    value:           '1'
+  - key:             readability-implicit-bool-conversion.AllowPointerConditions
+    value:           '1'
   - key:             readability-function-cognitive-complexity.Threshold
     value:           '25'
   - key:             readability-braces-around-statements.ShortStatementLines
diff --git a/mbo/container/any_scan.h b/mbo/container/any_scan.h
index 036da653..8f2b12b9 100644
--- a/mbo/container/any_scan.h
+++ b/mbo/container/any_scan.h
@@ -353,7 +353,7 @@ class AnyScanImpl {
   // For MakAnyScan / MakeConstScan
   template<AcceptableContainer Container>
   requires(kAccessByRef)
-  explicit AnyScanImpl(MakeAnyScanData<Container, kScanMode> data)
+  explicit AnyScanImpl(const MakeAnyScanData<Container, kScanMode>& data)
       : funcs_{
             .iter =
                 [data = data] {
@@ -374,7 +374,7 @@ class AnyScanImpl {
       !kAccessByRef  // This is the ConvertingScan constructor
       && types::ConstructibleFrom<AccessType, ::mbo::types::ContainerConstIteratorValueType<Container>>
       && types::ConstructibleFrom<value_type, AccessType>)
-  explicit AnyScanImpl(MakeAnyScanData<Container, kScanMode> data)
+  explicit AnyScanImpl(const MakeAnyScanData<Container, kScanMode>& data)
       : funcs_{
             // NOTE: data must be copied here!
             .iter =
diff --git a/mbo/hash/hash_differential_test.cc b/mbo/hash/hash_differential_test.cc
index 76a8cf58..d371014c 100644
--- a/mbo/hash/hash_differential_test.cc
+++ b/mbo/hash/hash_differential_test.cc
@@ -31,7 +31,11 @@
 namespace mbo::hash {
 namespace {
 
-// NOLINTBEGIN(*-magic-numbers)
+// readability-implicit-bool-conversion is suppressed rather than "fixed": inside
+// the reference macros (XXH64 / XXH3_*) it misattributes a conversion to the gtest
+// `<<` message chain, pointing at string literals like "len: " and proposing they
+// be replaced with `true`. Nothing here converts anything to bool.
+// NOLINTBEGIN(*-magic-numbers,readability-implicit-bool-conversion)
 
 TEST(DifferentialTest, Xxh64MatchesReference) {
   std::mt19937_64 rng(0xD1FF64U);  // NOLINT(cert-msc51-cpp,cert-msc32-c,bugprone-random-generator-seed): reproducible
@@ -89,7 +93,7 @@ TEST(DifferentialTest, Xxh3Hash128MatchesReference) {
   }
 }
 
-// NOLINTEND(*-magic-numbers)
+// NOLINTEND(*-magic-numbers,readability-implicit-bool-conversion)
 
 }  // namespace
 }  // namespace mbo::hash
diff --git a/mbo/strings/numbers.h b/mbo/strings/numbers.h
index f36588e9..346477bc 100644
--- a/mbo/strings/numbers.h
+++ b/mbo/strings/numbers.h
@@ -51,7 +51,7 @@ unsigned BigNumberLen(T v) {
   // We first check whether we can do even better by limiting us to 4 byte types.
   // We use a macro to let the compiler compute the actual length values.
   if constexpr (sizeof(v) <= 4) {
-#define CHECK_CAP(cap) std::make_pair<uint32_t, unsigned>(cap, std::string_view(#cap).size() - 3)
+#define CHECK_CAP(cap) std::pair<uint32_t, unsigned>(cap, std::string_view(#cap).size() - 3)
     constexpr auto kData = mbo::container::ToLimitedMap<std::pair<uint32_t, unsigned>>({
         CHECK_CAP(4'294'967'295ULL),
         CHECK_CAP(999'999'999ULL),
@@ -68,7 +68,7 @@ unsigned BigNumberLen(T v) {
 #undef CHECK_CAP
     return kData.lower_bound(v)->second;
   } else {
-#define CHECK_CAP(cap) std::make_pair<uint64_t, unsigned>(cap, std::string_view(#cap).size() - 3)
+#define CHECK_CAP(cap) std::pair<uint64_t, unsigned>(cap, std::string_view(#cap).size() - 3)
     constexpr auto kData = mbo::container::ToLimitedMap<std::pair<uint64_t, unsigned>>({
         CHECK_CAP(18'446'744'073'709'551'615ULL),
         CHECK_CAP(9'999'999'999'999'999'999ULL),