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import java.util.Objects;
import java.util.Optional;
import lombok.Builder;
import lombok.Value;
import lombok.experimental.Accessors;
import org.jspecify.annotations.NonNull;
import org.jspecify.annotations.Nullable;

@Value                    // ← Use Lombok's @Value to simulate Java Record
@Accessors(fluent = true) // ← Great choice to mimic Record accessors

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@Configuration
@Profile("routes-filter")
class FilterConfiguration {
  companion object {
    private val log = Loggers.getLogger(FilterConfiguration::class.java)
  }

  @Bean
  fun filterGateway(builder: RouteLocatorBuilder): RouteLocator =
    builder.routes()

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diff --git a/README.md b/README.md
index ced9bd0..d30d6ec 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,9 @@ Each module is implemented in both [Java](./java) and [Kotlin](./kotlin) to comp
 - Implemented parallel Kotlin versions of Java examples
 - Updated to Spring Boot 3.5.x while the book uses an older Spring Boot version 2.5.0
 - Adopted a monorepo approach with [Gradle Multi-project Builds][gradle-multiproject] and [Gradle Composite Builds][gradle-composite-builds] to manage both Java and Kotlin implementations in a single repository
+    - Learned that Gradle Kotlin DSL supports both type-safe and string-based dependency declarations, and that the string-based form was required
+        in [`08:rsocket/build.gradle.kts`](./kotlin/08-rsocket/build.gradle.kts) when adding dependencies inside `afterEvaluate`

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import java.util.ArrayList;
import java.util.List;
import java.util.function.Function;

class PricingDiscountApp {
  public static void main(String[] args) {
    final var customer1 = new Customer("1", "John Doe", CustomerType.VIP);
    final var customer2 = new Customer("2", "Jane Doe", CustomerType.REGULAR);
    final var customer3 = new Customer("3", "Business Corp", CustomerType.BUSINESS);

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import java.time.LocalDateTime;
import java.util.List;
import java.util.function.Function;
import java.util.stream.Collectors;

class DocumentProcessorApp {
  public static void main(String[] args) {
    final var trinity = new Submitter("trin123");
    final var morpheus = new Approver("morph456");

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import java.math.BigDecimal;
import java.time.Duration;
import java.time.LocalDateTime;
import java.util.*;
import java.util.stream.Collector;
import java.util.stream.Collectors;

class TripAnalyzerApp1 {
  private static final List<Trip> TRIPS = List.of(
      new Trip(TripType.BUSINESS, "Tokyo", Duration.ofHours(5),LocalDateTime.of(2025, 5, 25, 8, 0), "Thomas Anderson", new BigDecimal("1200.00")),

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import static java.time.temporal.ChronoUnit.HOURS;

import java.time.Instant;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.concurrent.atomic.AtomicLong;
import java.util.function.Function;
import java.util.function.Supplier;

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sealed interface Permission permits Read, Write {}
record Read() implements Permission {}
record Write() implements Permission {}

record Execute() {}

class ResourceAction {
  public String perform(Permission permission) {
    return String.format("Performing action with %s...", permission.getClass().getSimpleName());
  }

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// Basic domain record
public record Customer(String id, String email) {}

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type Functor<T> = {
  map<R>(fn: (val: T) => R): Functor<R>
  concat(other: Functor<T>, combiner: (a: T, b: T) => T): Functor<T>
  getValue(): T
}

function id<T>(value: T): Functor<T> {
  return {
    map<R>(fn: (val: T) => R): Functor<R> {
      return id(fn(value))