diff --git a/buildSrc/src/main/kotlin/Libs.kt b/buildSrc/src/main/kotlin/Libs.kt
index 079a29f..78bac7c 100644
--- a/buildSrc/src/main/kotlin/Libs.kt
+++ b/buildSrc/src/main/kotlin/Libs.kt
@@ -9,10 +9,7 @@ object Libs {
         const val fx = "io.arrow-kt:arrow-fx:$version"
     }
 
-    object EclipseCollection {
-        const val api = "org.eclipse.collections:eclipse-collections-api:10.4.0"
-        const val core = "org.eclipse.collections:eclipse-collections:10.4.0"
-    }
+    const val eclipseCollections = "org.eclipse.collections:eclipse-collections:10.4.0"
 
     object Jmh {
         const val core = "org.openjdk.jmh:jmh-core:1.26"
@@ -29,7 +26,7 @@ object Libs {
 
     object Slf4J {
         const val api = "org.slf4j:slf4j-api:1.7.25"
-        const val logback = "ch.qos.logback:logback-classic:1.2.3"
+        const val simple = "org.slf4j:slf4j-simple:1.7.30"
         const val kotlin = "io.github.microutils:kotlin-logging-jvm:2.0.3"
     }
 
diff --git a/buildSrc/src/main/kotlin/kotlin-convention.gradle.kts b/buildSrc/src/main/kotlin/kotlin-convention.gradle.kts
index 6af74db..0a30fe0 100644
--- a/buildSrc/src/main/kotlin/kotlin-convention.gradle.kts
+++ b/buildSrc/src/main/kotlin/kotlin-convention.gradle.kts
@@ -12,7 +12,7 @@ dependencies {
 
 tasks.withType<KotlinCompile> {
     kotlinOptions {
-        jvmTarget = "15"
+        jvmTarget = "14"
         javaParameters = true
         freeCompilerArgs = listOf(
             "-Xinline-classes",
diff --git a/days/build.gradle.kts b/days/build.gradle.kts
index 8e631cf..fcb2f96 100644
--- a/days/build.gradle.kts
+++ b/days/build.gradle.kts
@@ -10,4 +10,12 @@ dependencies {
     implementation(Libs.Micronaut.inject)
     implementation(Libs.Micronaut.kotlin)
     kapt(Libs.Micronaut.processor)
+
+    implementation(Libs.eclipseCollections) {
+        because("Primitive collections mostly")
+    }
+
+    implementation(Libs.Arrow.core) {
+        because("Just in case")
+    }
 }
diff --git a/utils/build.gradle.kts b/utils/build.gradle.kts
index 245cf80..4144864 100644
--- a/utils/build.gradle.kts
+++ b/utils/build.gradle.kts
@@ -11,7 +11,7 @@ dependencies {
 
     implementation(Libs.Slf4J.api)
     implementation(Libs.Slf4J.kotlin)
-    runtimeOnly(Libs.Slf4J.logback)
+    runtimeOnly(Libs.Slf4J.simple)
 
     testImplementation(Libs.Tests.jimfs)
     kaptTest(Libs.Micronaut.processor)
diff --git a/utils/src/main/resources/logback.xml b/utils/src/main/resources/logback.xml
deleted file mode 100644
index e391c7a..0000000
--- a/utils/src/main/resources/logback.xml
+++ /dev/null
@@ -1,14 +0,0 @@
-<configuration>
-    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-        <withJansi>true</withJansi>
-        <encoder>
-            <pattern>%cyan(%d{YYYY-MM-dd HH:mm:ss.SSS}) [%thread] %highlight(%-5level) %green(%logger{36}) - %msg%n
-            </pattern>
-        </encoder>
-    </appender>
-    <root level="INFO">
-        <appender-ref ref="STDOUT"/>
-    </root>
-    <logger name="io.micronaut" level="INFO"/>
-    <logger name="io.micronaut.context.lifecycle" level="INFO"/>
-</configuration>
diff --git a/utils/src/main/resources/simplelogger.properties b/utils/src/main/resources/simplelogger.properties
new file mode 100644
index 0000000..b4dd2ef
--- /dev/null
+++ b/utils/src/main/resources/simplelogger.properties
@@ -0,0 +1,6 @@
+org.slf4j.simpleLogger.logFile=System.out
+org.slf4j.simpleLogger.showDateTime=true
+org.slf4j.simpleLogger.dateTimeFormat=yyyy-MM-dd HH:mm:ss:SSS Z
+org.slf4j.simpleLogger.defaultLogLevel=info
+org.slf4j.simpleLogger.log.io.micronaut=info
+org.slf4j.simpleLogger.log.io.micronaut.context.lifecycle=info