diff --git a/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/authorizations/commands/StartAuthorizationCommand.kt b/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/authorizations/commands/StartAuthorizationCommand.kt
index 616f574..f247fe2 100644
--- a/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/authorizations/commands/StartAuthorizationCommand.kt
+++ b/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/authorizations/commands/StartAuthorizationCommand.kt
@@ -23,7 +23,7 @@ internal object StartAuthorizationCommand : RSocketCommand<StartAuthorizationReq
         ).let { result ->
             StartAuthorizationRequest.Result(
                 verificationHash = VerificationHash.createOrThrow(result.verificationHash),
-                attempts = Count.createOrThrow(result.attempts),
+                attempts = Count.factory.createOrThrow(result.attempts),
                 expiresAt = Instant.fromEpochMilliseconds(result.expiresAt),
             )
         }
diff --git a/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/timers/TimerMappers.kt b/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/timers/TimerMappers.kt
index bd623ca..a54dba3 100644
--- a/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/timers/TimerMappers.kt
+++ b/rsocket-engine/src/main/kotlin/org/timemates/api/rsocket/timers/TimerMappers.kt
@@ -27,7 +27,7 @@ internal fun RSTimer.sdk(): SdkTimer {
         name = TimerName.createOrThrow(name),
         description = TimerDescription.createOrThrow(description),
         ownerId = UserId.createOrThrow(ownerId),
-        membersCount = Count.createOrThrow(membersCount),
+        membersCount = Count.factory.createOrThrow(membersCount),
         state = currentState?.sdk() ?: SdkTimerState.Inactive(Instant.DISTANT_PAST),
         settings = settings?.sdk() ?: TimerSettings(),
     )
@@ -64,7 +64,7 @@ internal fun RSTimer.Settings.sdk(): SdkTimerSettings {
         restTime = restTime.minutes,
         bigRestTime = bigRestTime.minutes,
         bigRestEnabled = bigRestEnabled,
-        bigRestPer = Count.createOrThrow(bigRestPer),
+        bigRestPer = Count.factory.createOrThrow(bigRestPer),
         isEveryoneCanPause = isEveryoneCanPause,
         isConfirmationRequired = isConfirmationRequired,
     )
@@ -84,6 +84,6 @@ internal fun RSInvite.sdk(): SdkInvite {
     return SdkInvite(
         inviteCode = InviteCode.createOrThrow(code),
         creationTime = Instant.fromEpochMilliseconds(creationTime),
-        limit = Count.createOrThrow(limit),
+        limit = Count.factory.createOrThrow(limit),
     )
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/email/types/value/VerificationHash.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/email/types/value/VerificationHash.kt
index c301c73..fd65cfb 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/email/types/value/VerificationHash.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/email/types/value/VerificationHash.kt
@@ -5,13 +5,20 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthExact
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class VerificationHash private constructor(public val string: String) {
-    public companion object : Factory<VerificationHash, String> by factory(
-        rules = listOf(
-            ValidationRule.lengthExact(128),
-        ),
-        constructor = ::VerificationHash
-    )
+    public companion object {
+        @JvmStatic
+        public val REQUIRED_LENGTH: Int = 128
+
+        @JvmStatic
+        public val factory: Factory<VerificationHash, String> = factory(
+            rules = listOf(
+                ValidationRule.lengthExact(REQUIRED_LENGTH),
+            ),
+            constructor = ::VerificationHash
+        )
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/AuthorizedSessionsApi.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/AuthorizedSessionsApi.kt
index 68d3dc6..371753a 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/AuthorizedSessionsApi.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/AuthorizedSessionsApi.kt
@@ -55,7 +55,7 @@ public class AuthorizedSessionsApi(
 @Suppress("NAME_SHADOWING")
 public fun AuthorizedSessionsApi.getSessionsPages(
     pageToken: PageToken?,
-    maxRetries: Count = Count.createOrThrow(5),
+    maxRetries: Count = Count.factory.createOrThrow(5),
     initialDelayOnRetries: Duration = 1.seconds,
 ): PagesIterator<Authorization> = PagesIteratorImpl(
     initialPageToken = pageToken,
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ApplicationName.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ApplicationName.kt
index 461bbc4..59f5070 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ApplicationName.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ApplicationName.kt
@@ -3,8 +3,12 @@ package org.timemates.sdk.authorization.sessions.types.value
 import org.timemates.sdk.common.constructor.Factory
 import org.timemates.sdk.common.constructor.factory
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class ApplicationName private constructor(public val string: String) {
-    public companion object : Factory<ApplicationName, String> by factory(::ApplicationName)
+    public companion object {
+        @JvmStatic
+        public val factory: Factory<ApplicationName, String> = factory(::ApplicationName)
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/AuthorizationId.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/AuthorizationId.kt
index 46508a4..948fe44 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/AuthorizationId.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/AuthorizationId.kt
@@ -3,8 +3,12 @@ package org.timemates.sdk.authorization.sessions.types.value
 import org.timemates.sdk.common.constructor.Factory
 import org.timemates.sdk.common.constructor.factory
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class AuthorizationId private constructor(public val int: Int) {
-    public companion object : Factory<AuthorizationId, Int> by factory(::AuthorizationId)
+    public companion object {
+        @JvmStatic
+        public val factory: Factory<AuthorizationId, Int> = factory(::AuthorizationId)
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientIpAddress.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientIpAddress.kt
index 7d75e4f..23360a9 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientIpAddress.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientIpAddress.kt
@@ -3,8 +3,12 @@ package org.timemates.sdk.authorization.sessions.types.value
 import org.timemates.sdk.common.constructor.Factory
 import org.timemates.sdk.common.constructor.factory
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class ClientIpAddress private constructor(public val string: String) {
-    public companion object : Factory<ClientIpAddress, String> by factory(::ClientIpAddress)
+    public companion object {
+        @JvmStatic
+        public val factory: Factory<ClientIpAddress, String> = factory(::ClientIpAddress)
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientVersion.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientVersion.kt
index 6685125..c617248 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientVersion.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ClientVersion.kt
@@ -3,8 +3,12 @@ package org.timemates.sdk.authorization.sessions.types.value
 import org.timemates.sdk.common.constructor.Factory
 import org.timemates.sdk.common.constructor.factory
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class ClientVersion private constructor(public val double: Double) {
-    public companion object : Factory<ClientVersion, Double> by factory(::ClientVersion)
+    public companion object {
+        @JvmStatic
+        public val factory: Factory<ClientVersion, Double> = factory(::ClientVersion)
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ConfirmationCode.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ConfirmationCode.kt
index 199a024..09d5a79 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ConfirmationCode.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/sessions/types/value/ConfirmationCode.kt
@@ -6,14 +6,20 @@ import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthExact
 import org.timemates.sdk.common.constructor.rules.notBlank
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class ConfirmationCode private constructor(public val string: String) {
-    public companion object : Factory<ConfirmationCode, String> by factory(
-        rules = listOf(
-            ValidationRule.notBlank(),
-            ValidationRule.lengthExact(8),
-        ),
-        constructor = ::ConfirmationCode,
-    )
+    public companion object {
+        @JvmStatic
+        public val REQUIRED_LENGTH: Int = 8
+
+        public val factory: Factory<ConfirmationCode, String> = factory(
+            rules = listOf(
+                ValidationRule.notBlank(),
+                ValidationRule.lengthExact(REQUIRED_LENGTH),
+            ),
+            constructor = ::ConfirmationCode,
+        )
+    }
 }
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/types/value/HashValue.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/types/value/HashValue.kt
index dbeca81..43e35a4 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/types/value/HashValue.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/authorization/types/value/HashValue.kt
@@ -3,10 +3,12 @@ package org.timemates.sdk.authorization.types.value
 import org.timemates.sdk.common.constructor.Factory
 import org.timemates.sdk.common.constructor.factory
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class HashValue private constructor(public val string: String) {
-    public companion object : Factory<HashValue, String> by factory(
-        constructor = ::HashValue,
-    )
+    public companion object {
+        @JvmStatic
+        public val factory: Factory<HashValue, String> = factory(constructor = ::HashValue)
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/constructor/Factory.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/constructor/Factory.kt
index dbb4731..f18fb0d 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/constructor/Factory.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/constructor/Factory.kt
@@ -17,6 +17,12 @@ import org.timemates.sdk.common.constructor.results.getUnsafe
  * @param TRaw The type of TRaw used to create the object.
  */
 public interface Factory<TBoxed, TRaw> {
+
+    /**
+     * Validation rules that apply to the creation of [TBoxed] by contract of this factory.
+     *
+     * @see ValidationRule
+     */
     public val rules: List<ValidationRule<TRaw>>
 
 
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PageToken.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PageToken.kt
index 1801ca7..affda23 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PageToken.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PageToken.kt
@@ -3,6 +3,7 @@ package org.timemates.sdk.common.pagination
 import org.timemates.sdk.common.constructor.Factory
 import org.timemates.sdk.common.constructor.factory
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 /**
  * A value class representing a page token.
@@ -13,5 +14,8 @@ import kotlin.jvm.JvmInline
  */
 @JvmInline
 public value class PageToken private constructor(public val string: String) {
-    public companion object : Factory<PageToken, String> by factory(::PageToken)
+    public companion object {
+        @JvmStatic
+        public val factory: Factory<PageToken, String> = factory(::PageToken)
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PagesIterator.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PagesIterator.kt
index d7aa676..81678c2 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PagesIterator.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/pagination/PagesIterator.kt
@@ -141,12 +141,12 @@ public fun <T, R> PagesIterator<T>.map(mapper: suspend (T) -> R): PagesIterator<
  * on every retry.
  */
 internal class PagesIteratorImpl<T : TimeMatesEntity>(
-    private val chunkSize: Count = Count.createOrThrow(20),
+    private val chunkSize: Count = Count.factory.createOrThrow(20),
     private val initialPageToken: PageToken?,
     prevPage: Page<T>? = null,
     private val provider: suspend (size: Count, pageToken: PageToken?) -> Result<Page<T>>,
     private val delayOnServerErrors: Duration,
-    private val maxRetries: Count = Count.createOrThrow(5),
+    private val maxRetries: Count = Count.factory.createOrThrow(5),
     private val increaseDelayOnRetries: Boolean = true,
 ) : PagesIterator<T> {
     /**
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/types/value/Count.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/types/value/Count.kt
index d02ddc8..75c929c 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/common/types/value/Count.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/common/types/value/Count.kt
@@ -5,13 +5,17 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.minValue
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class Count private constructor(public val int: Int) {
-    public companion object : Factory<Count, Int> by factory(
-        rules = listOf(ValidationRule.minValue(Count.MIN_REQUIRED_VALUE)),
-        constructor = ::Count,
-    )
-}
+    public companion object {
+        public const val MIN_VALUE: Int = 0
 
-public val Count.Companion.MIN_REQUIRED_VALUE: Int get() = 0
\ No newline at end of file
+        @JvmStatic
+        public val factory: Factory<Count, Int> = factory(
+            rules = listOf(ValidationRule.minValue(MIN_VALUE)),
+            constructor = ::Count,
+        )
+    }
+}
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/TimersApi.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/TimersApi.kt
index a9343f8..42cd6bd 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/TimersApi.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/TimersApi.kt
@@ -112,7 +112,7 @@ public class TimersApi(
 
 public fun TimersApi.getUserTimersPages(
     pageToken: PageToken? = null,
-    maxRetries: Count = Count.createOrThrow(5),
+    maxRetries: Count = Count.factory.createOrThrow(5),
     initialDelayOnRetries: Duration = 1.seconds,
 ): PagesIterator<Timer> = PagesIteratorImpl(
     initialPageToken = pageToken,
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/TimerMembersApi.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/TimerMembersApi.kt
index 28c0bea..217de25 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/TimerMembersApi.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/TimerMembersApi.kt
@@ -64,7 +64,7 @@ public class TimerMembersApi(
 public fun TimerMembersApi.getMembersPages(
     timerId: TimerId,
     pageToken: PageToken? = null,
-    maxRetries: Count = Count.createOrThrow(5),
+    maxRetries: Count = Count.factory.createOrThrow(5),
     initialDelayOnRetries: Duration = 1.seconds,
 ): PagesIterator<User> = PagesIteratorImpl(
     initialPageToken = pageToken,
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/TimerInvitesApi.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/TimerInvitesApi.kt
index 1ba00b8..f93f4d8 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/TimerInvitesApi.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/TimerInvitesApi.kt
@@ -72,7 +72,7 @@ public class TimerInvitesApi(
 public fun TimerInvitesApi.getInvitesPages(
     timerId: TimerId,
     pageToken: PageToken? = null,
-    maxRetries: Count = Count.createOrThrow(5),
+    maxRetries: Count = Count.factory.createOrThrow(5),
     initialDelayOnRetries: Duration = 1.seconds,
 ): PagesIterator<Invite> = PagesIteratorImpl(
     initialPageToken = pageToken,
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteCode.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteCode.kt
index 93008b5..c36efd2 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteCode.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteCode.kt
@@ -5,13 +5,17 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthExact
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class InviteCode private constructor(public val string: String) {
-    public companion object : Factory<InviteCode, String> by factory(
-        rules = listOf(ValidationRule.lengthExact(InviteCode.REQUIRED_LENGTH)),
-        constructor = ::InviteCode,
-    )
-}
+    public companion object {
+        public const val REQUIRED_LENGTH: Int = 8
 
-public val InviteCode.Companion.REQUIRED_LENGTH: Int get() = 8
\ No newline at end of file
+        @JvmStatic
+        public val factory: Factory<InviteCode, String> = factory(
+            rules = listOf(ValidationRule.lengthExact(InviteCode.REQUIRED_LENGTH)),
+            constructor = ::InviteCode,
+        )
+    }
+}
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteName.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteName.kt
index 6796078..e8f219b 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteName.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/members/invites/types/value/InviteName.kt
@@ -5,13 +5,17 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.notBlank
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class InviteName private constructor(public val string: String) {
-    public companion object : Factory<InviteName, String> by factory(
-        rules = listOf(
-            ValidationRule.notBlank(),
-        ),
-        constructor = ::InviteName
-    )
+    public companion object {
+        @JvmStatic
+        public val factory: Factory<InviteName, String> = factory(
+            rules = listOf(
+                ValidationRule.notBlank(),
+            ),
+            constructor = ::InviteName
+        )
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/TimerSettings.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/TimerSettings.kt
index 2338f02..82f77b8 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/TimerSettings.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/TimerSettings.kt
@@ -11,7 +11,7 @@ public data class TimerSettings(
     val restTime: Duration = 5.minutes,
     val bigRestTime: Duration = 10.minutes,
     val bigRestEnabled: Boolean = true,
-    val bigRestPer: Count = Count.createOrThrow(4),
+    val bigRestPer: Count = Count.factory.createOrThrow(4),
     val isEveryoneCanPause: Boolean = false,
     val isConfirmationRequired: Boolean = false,
 ) : TimeMatesEntity() {
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerDescription.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerDescription.kt
index 6b0377a..a877d1b 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerDescription.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerDescription.kt
@@ -5,15 +5,20 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthRange
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class TimerDescription private constructor(public val string: String) {
-    public companion object : Factory<TimerDescription, String> by factory(
-        rules = listOf(
-            ValidationRule.lengthRange(TimerDescription.LENGTH_RANGE),
-        ),
-        constructor = ::TimerDescription,
-    )
-}
+    public companion object {
+        @JvmStatic
+        public val LENGTH_RANGE: IntRange = 0..500
 
-public val TimerDescription.Companion.LENGTH_RANGE: IntRange get() = 0..500
\ No newline at end of file
+        @JvmStatic
+        public val factory: Factory<TimerDescription, String> = factory(
+            rules = listOf(
+                ValidationRule.lengthRange(LENGTH_RANGE),
+            ),
+            constructor = ::TimerDescription,
+        )
+    }
+}
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerId.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerId.kt
index 289343f..56cfe8e 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerId.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerId.kt
@@ -5,13 +5,19 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.minValue
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class TimerId private constructor(public val long: Long) {
-    public companion object : Factory<TimerId, Long> by factory(
-        rules = listOf(
-            ValidationRule.minValue(0),
-        ),
-        constructor = ::TimerId,
-    )
+    public companion object {
+        public const val MIN_VALUE: Long = 0L
+
+        @JvmStatic
+        public val factory: Factory<TimerId, Long> = factory(
+            rules = listOf(
+                ValidationRule.minValue(MIN_VALUE),
+            ),
+            constructor = ::TimerId,
+        )
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerName.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerName.kt
index 4053592..a7379b3 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerName.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/timers/types/value/TimerName.kt
@@ -5,15 +5,20 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthRange
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class TimerName private constructor(public val string: String) {
-    public companion object : Factory<TimerName, String> by factory(
-        rules = listOf(
-            ValidationRule.lengthRange(TimerName.LENGTH_RANGE),
-        ),
-        constructor = ::TimerName,
-    )
-}
+    public companion object {
+        @JvmStatic
+        public val LENGTH_RANGE: IntRange = 3..50
 
-public val TimerName.Companion.LENGTH_RANGE: IntRange get() = 3..50
\ No newline at end of file
+        @JvmStatic
+        public val factory: Factory<TimerName, String> = factory(
+            rules = listOf(
+                ValidationRule.lengthRange(LENGTH_RANGE),
+            ),
+            constructor = ::TimerName,
+        )
+    }
+}
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/Avatar.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/Avatar.kt
index 3517273..cc2065c 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/Avatar.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/Avatar.kt
@@ -5,13 +5,17 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.notBlank
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 public sealed interface Avatar {
     @JvmInline
     public value class GravatarId private constructor(public val string: String) : Avatar {
-        public companion object : Factory<GravatarId, String> by factory(
-            rules = listOf(ValidationRule.notBlank()),
-            constructor = ::GravatarId,
-        )
+        public companion object {
+            @JvmStatic
+            public val factory: Factory<GravatarId, String> = factory(
+                rules = listOf(ValidationRule.notBlank()),
+                constructor = ::GravatarId,
+            )
+        }
     }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/EmailAddress.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/EmailAddress.kt
index 388817f..b14e5e2 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/EmailAddress.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/EmailAddress.kt
@@ -6,26 +6,34 @@ import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthRange
 import org.timemates.sdk.common.constructor.rules.matchesPattern
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class EmailAddress private constructor(public val string: String) {
-    public companion object : Factory<EmailAddress, String> by factory(
-        rules = listOf(
-            ValidationRule.lengthRange(EmailAddress.LENGTH_RANGE),
-            ValidationRule.matchesPattern(EmailAddress.EMAIL_PATTERN),
-        ),
-        constructor = ::EmailAddress,
-    )
-}
+    public companion object {
+        @JvmStatic
+        public val LENGTH_RANGE: IntRange = 5..200
 
-public val EmailAddress.Companion.LENGTH_RANGE: IntRange get() = 5..200
+        @JvmStatic
+        public val EMAIL_PATTERN: Regex = Regex(
+            buildString {
+                append("[a-zA-Z0-9\\+\\.\\_\\%\\-\\+]{1,256}")
+                append("\\@")
+                append("[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}")
+                append("(")
+                append("\\.")
+                append("[a-zA-Z0-9][a-zA-Z0-9\\-]{0,25}")
+                append(")+")
+            }
+        )
 
-public val EmailAddress.Companion.EMAIL_PATTERN: Regex get() = Regex(
-    "[a-zA-Z0-9\\+\\.\\_\\%\\-\\+]{1,256}" +
-        "\\@" +
-        "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}" +
-        "(" +
-        "\\." +
-        "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,25}" +
-        ")+"
-)
\ No newline at end of file
+        @JvmStatic
+        public val factory: Factory<EmailAddress, String> = factory(
+            rules = listOf(
+                ValidationRule.lengthRange(LENGTH_RANGE),
+                ValidationRule.matchesPattern(EMAIL_PATTERN),
+            ),
+            constructor = ::EmailAddress,
+        )
+    }
+}
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserDescription.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserDescription.kt
index a2c3b24..8176fda 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserDescription.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserDescription.kt
@@ -5,15 +5,20 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthRange
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class UserDescription private constructor(public val string: String) {
-    public companion object : Factory<UserDescription, String> by factory(
-        rules = listOf(
-            ValidationRule.lengthRange(UserDescription.LENGTH_RANGE),
-        ),
-        constructor = ::UserDescription,
-    )
-}
+    public companion object {
+        @JvmStatic
+        public val LENGTH_RANGE: IntRange = 3..200
 
-public val UserDescription.Companion.LENGTH_RANGE: IntRange get() = 3..200
+        @JvmStatic
+        public val factory: Factory<UserDescription, String> = factory(
+            rules = listOf(
+                ValidationRule.lengthRange(LENGTH_RANGE),
+            ),
+            constructor = ::UserDescription,
+        )
+    }
+}
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserId.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserId.kt
index c1c0e96..2060509 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserId.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserId.kt
@@ -5,11 +5,17 @@ import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.minValue
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class UserId private constructor(public val long: Long) {
-    public companion object : Factory<UserId, Long> by factory(
-        rules = listOf(ValidationRule.minValue(0)),
-        constructor = ::UserId,
-    )
+    public companion object {
+        public const val MIN_VALUE: Long = 0
+
+        @JvmStatic
+        public val factory: Factory<UserId, Long> = factory(
+            rules = listOf(ValidationRule.minValue(MIN_VALUE)),
+            constructor = ::UserId,
+        )
+    }
 }
\ No newline at end of file
diff --git a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserName.kt b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserName.kt
index 18f8e74..036ff3b 100644
--- a/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserName.kt
+++ b/sdk/src/commonMain/kotlin/org/timemates/sdk/users/profile/types/value/UserName.kt
@@ -1,17 +1,25 @@
 package org.timemates.sdk.users.profile.types.value
 
 import org.timemates.sdk.common.constructor.Factory
+import org.timemates.sdk.common.constructor.createOrThrow
 import org.timemates.sdk.common.constructor.factory
 import org.timemates.sdk.common.constructor.rules.ValidationRule
 import org.timemates.sdk.common.constructor.rules.lengthRange
 import kotlin.jvm.JvmInline
+import kotlin.jvm.JvmStatic
 
 @JvmInline
 public value class UserName private constructor(public val string: String) {
-    public companion object : Factory<UserName, String> by factory(
-        rules = listOf(ValidationRule.lengthRange(UserName.LENGTH_RANGE)),
-        constructor = ::UserName,
-    )
+    public companion object {
+        @JvmStatic
+        public val LENGTH_RANGE: IntRange = 3..50
+
+        @JvmStatic
+        public val factory: Factory<UserName, String> = factory(
+            rules = listOf(ValidationRule.lengthRange(LENGTH_RANGE)),
+            constructor = ::UserName,
+        )
+    }
 }
 
-public val UserName.Companion.LENGTH_RANGE: IntRange get() = 3..50
+