diff --git a/build.gradle.kts b/build.gradle.kts
index 4dc6e1ed..5cf32e2b 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -264,6 +264,7 @@ mavenPublishing {
 dependencies {
     annotationProcessor(libs.nullaway)
     api(libs.protobuf.java)
+    implementation(libs.protobuf.java.util)
     implementation(enforcedPlatform(libs.cel))
     implementation(libs.cel.core)
     implementation(libs.guava)
diff --git a/gradle.properties b/gradle.properties
index 0e405393..9e884fbc 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -2,7 +2,7 @@
 protovalidate.version = v0.8.2
 
 # Arguments to the protovalidate-conformance CLI
-protovalidate.conformance.args = --strict_message --strict_error
+protovalidate.conformance.args = --strict --strict_message --strict_error
 
 # Argument to the license-header CLI
 license-header.years = 2023-2024
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 4dd17333..1f5ab97a 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -25,6 +25,7 @@ junit-bom = { module = "org.junit:junit-bom", version.ref = "junit" }
 maven-plugin = { module = "com.vanniktech:gradle-maven-publish-plugin", version.ref = "maven-publish" }
 nullaway = { module = "com.uber.nullaway:nullaway", version = "0.12.1" }
 protobuf-java = { module = "com.google.protobuf:protobuf-java", version.ref = "protobuf" }
+protobuf-java-util = { module = "com.google.protobuf:protobuf-java-util", version.ref = "protobuf" }
 spotless = { module = "com.diffplug.spotless:spotless-plugin-gradle", version = "6.25.0" }
 
 [plugins]
diff --git a/src/main/java/build/buf/protovalidate/internal/celext/Format.java b/src/main/java/build/buf/protovalidate/internal/celext/Format.java
index df662494..ef5975db 100644
--- a/src/main/java/build/buf/protovalidate/internal/celext/Format.java
+++ b/src/main/java/build/buf/protovalidate/internal/celext/Format.java
@@ -16,6 +16,7 @@
 
 import com.google.protobuf.Duration;
 import com.google.protobuf.Timestamp;
+import com.google.protobuf.util.Timestamps;
 import java.nio.charset.StandardCharsets;
 import java.text.DecimalFormat;
 import java.util.List;
@@ -139,7 +140,10 @@ private static void formatString(StringBuilder builder, Val val) {
     if (val.type().typeEnum() == TypeEnum.String) {
       builder.append(val.value());
     } else if (val.type().typeEnum() == TypeEnum.Bytes) {
-      builder.append(val.value());
+      builder.append(new String((byte[]) val.value(), StandardCharsets.UTF_8));
+    } else if (val.type().typeEnum() == TypeEnum.Double) {
+      DecimalFormat format = new DecimalFormat();
+      builder.append(format.format(val.value()));
     } else {
       formatStringSafe(builder, val, false);
     }
@@ -159,7 +163,11 @@ private static void formatStringSafe(StringBuilder builder, Val val, boolean lis
     } else if (type == TypeEnum.Int || type == TypeEnum.Uint) {
       formatDecimal(builder, val);
     } else if (type == TypeEnum.Double) {
-      DecimalFormat format = new DecimalFormat("0.#");
+      // When a double is nested in another type (e.g. a list) it will have a minimum of 6 decimal
+      // digits. This is to maintain consistency with the Go CEL runtime.
+      DecimalFormat format = new DecimalFormat();
+      format.setMaximumFractionDigits(Integer.MAX_VALUE);
+      format.setMinimumFractionDigits(6);
       builder.append(format.format(val.value()));
     } else if (type == TypeEnum.String) {
       builder.append("\"").append(val.value().toString()).append("\"");
@@ -205,10 +213,8 @@ private static void formatList(StringBuilder builder, Val val) {
    * @param val the value to format.
    */
   private static void formatTimestamp(StringBuilder builder, Val val) {
-    builder.append("timestamp(");
     Timestamp timestamp = val.convertToNative(Timestamp.class);
-    builder.append(timestamp.toString());
-    builder.append(")");
+    builder.append(Timestamps.toString(timestamp));
   }
 
   /**
diff --git a/src/main/java/build/buf/protovalidate/internal/evaluator/MapEvaluator.java b/src/main/java/build/buf/protovalidate/internal/evaluator/MapEvaluator.java
index a2894dfe..3110d390 100644
--- a/src/main/java/build/buf/protovalidate/internal/evaluator/MapEvaluator.java
+++ b/src/main/java/build/buf/protovalidate/internal/evaluator/MapEvaluator.java
@@ -23,6 +23,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 
 /** Performs validation on a map field's key-value pairs. */
 class MapEvaluator implements Evaluator {
@@ -84,7 +85,10 @@ public ValidationResult evaluate(Value val, boolean failFast) throws ExecutionEx
 
   private List<Violation> evalPairs(Value key, Value value, boolean failFast)
       throws ExecutionException {
-    List<Violation> keyViolations = keyEvaluator.evaluate(key, failFast).getViolations();
+    List<Violation> keyViolations =
+        keyEvaluator.evaluate(key, failFast).getViolations().stream()
+            .map(violation -> violation.toBuilder().setForKey(true).build())
+            .collect(Collectors.toList());
     final List<Violation> valueViolations;
     if (failFast && !keyViolations.isEmpty()) {
       // Don't evaluate value constraints if failFast is enabled and keys failed validation.