diff --git a/build.gradle b/build.gradle
index f333772..cfc3cdb 100644
--- a/build.gradle
+++ b/build.gradle
@@ -24,6 +24,12 @@ repositories {
 apply from: 'buildsystem/ci.gradle'
 apply from: 'buildsystem/dependencies.gradle'
 
+tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).all {
+    kotlinOptions {
+        jvmTarget = "1.8"
+    }
+}
+
 dependencies {
     implementation apiDependencies.kotlinJdk
     implementation apiDependencies.kotlinCoroutines
diff --git a/buildsystem/ci.gradle b/buildsystem/ci.gradle
index d3fc871..cade278 100644
--- a/buildsystem/ci.gradle
+++ b/buildsystem/ci.gradle
@@ -11,7 +11,7 @@ ext {
     siteUrl = 'https://github.com/coinpaprika/coinpaprika-api-kotlin-client'
     gitUrl = 'https://github.com/coinpaprika/coinpaprika-api-kotlin-client.git'
 
-    libraryVersion = '0.4.3'
+    libraryVersion = '0.4.4'
 
     developerId = 'coinpaprika'
     developerName = 'CoinPaprika'
diff --git a/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApi.kt b/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApi.kt
index 2e827b0..c2d0ca9 100644
--- a/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApi.kt
@@ -11,18 +11,20 @@ import com.coinpaprika.apiclient.repository.search.SearchApi
 import com.coinpaprika.apiclient.repository.tag.TagApi
 import com.coinpaprika.apiclient.repository.ticker.TickerApi
 import io.reactivex.Observable
-
-open class CoinpaprikaApi {
-
-    private var tickerApi = TickerApi()
-    private var coinApi = CoinApi()
-    private var tagApi = TagApi()
-    private var peopleApi = PeopleApi()
-    private var searchApi = SearchApi()
-    private var newsApi = NewsApi()
-    private var rankingApi = RankingApi()
-    private var globalApi = GlobalApi()
-    private var fiatApi = FiatApi()
+import retrofit2.Retrofit
+import retrofit2.create
+
+open class CoinpaprikaApi(retrofit: Retrofit) {
+
+    private var tickerApi = TickerApi(retrofit.create())
+    private var coinApi = CoinApi(retrofit.create())
+    private var tagApi = TagApi(retrofit.create())
+    private var peopleApi = PeopleApi(retrofit.create())
+    private var searchApi = SearchApi(retrofit.create())
+    private var newsApi = NewsApi(retrofit.create())
+    private var rankingApi = RankingApi(retrofit.create())
+    private var globalApi = GlobalApi(retrofit.create())
+    private var fiatApi = FiatApi(retrofit.create())
 
     suspend fun ticker(id: String, quotes: String? = null): TickerEntity {
         return tickerApi.getTicker(id, quotes)
diff --git a/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApiFactory.kt b/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApiFactory.kt
index 755942c..cee80a0 100644
--- a/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApiFactory.kt
+++ b/src/main/java/com/coinpaprika/apiclient/api/CoinpaprikaApiFactory.kt
@@ -1,36 +1,14 @@
-/*
- * Created by Piotr Kostecki on 5/16/19 4:05 PM
- */
-
 package com.coinpaprika.apiclient.api
 
 import com.jakewharton.retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory
-import okhttp3.ConnectionPool
 import okhttp3.OkHttpClient
-import okhttp3.Protocol
 import retrofit2.Retrofit
 import retrofit2.converter.gson.GsonConverterFactory
-import java.util.concurrent.TimeUnit
-
-
-fun defaultClient(): OkHttpClient.Builder {
-    return OkHttpClient.Builder()
-        .protocols(listOf(Protocol.HTTP_1_1, Protocol.HTTP_2))
-        .connectTimeout(30, TimeUnit.SECONDS)
-        .readTimeout(30, TimeUnit.SECONDS)
-        .writeTimeout(30, TimeUnit.SECONDS)
-        .retryOnConnectionFailure(true)
-        .connectionPool(ConnectionPool(0, 1, TimeUnit.NANOSECONDS))
-}
-
-class CoinpaprikaApiFactory(private val client: OkHttpClient = defaultClient().build()) {
-    companion object {
-        private const val BASE_URL = "https://api.coinpaprika.com/v1/"
-    }
 
-    fun client(): Retrofit {
+object CoinpaprikaApiFactory {
+    fun getRetrofit(client: OkHttpClient): Retrofit {
         return Retrofit.Builder()
-            .baseUrl(BASE_URL)
+            .baseUrl("https://api.coinpaprika.com/v1/")
             .addConverterFactory(GsonConverterFactory.create())
             .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
             .client(client)
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/coin/CoinApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/coin/CoinApi.kt
index 65ef0cc..05aeebb 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/coin/CoinApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/coin/CoinApi.kt
@@ -1,42 +1,37 @@
 package com.coinpaprika.apiclient.repository.coin
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.*
 import com.coinpaprika.apiclient.extensions.safeApiCallRaw
 import io.reactivex.Observable
 import retrofit2.Response
 
-class CoinApi constructor(
-    private var retrofit: CoinApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(CoinApiContract::class.java)
-) : CoinApiContract {
+class CoinApi(private var contract: CoinApiContract) : CoinApiContract {
 
     override suspend fun getCoin(id: String): CoinDetailsEntity {
-        return retrofit.getCoin(id)
+        return contract.getCoin(id)
     }
 
     override suspend fun getCoins(additionalFields: String?): List<CoinEntity> {
-        return retrofit.getCoins(additionalFields)
+        return contract.getCoins(additionalFields)
     }
 
     override fun getEvents(id: String): Observable<Response<List<EventEntity>>> {
-        return safeApiCallRaw { retrofit.getEvents(id) }
+        return safeApiCallRaw { contract.getEvents(id) }
     }
 
     override fun getExchanges(id: String): Observable<Response<List<ExchangeEntity>>> {
-        return safeApiCallRaw { retrofit.getExchanges(id) }
+        return safeApiCallRaw { contract.getExchanges(id) }
     }
 
     override fun getMarkets(id: String, quotes: String): Observable<Response<List<MarketEntity>>> {
-        return safeApiCallRaw { retrofit.getMarkets(id, quotes) }
+        return safeApiCallRaw { contract.getMarkets(id, quotes) }
     }
 
     override fun getTweets(id: String): Observable<Response<List<TweetEntity>>> {
-        return safeApiCallRaw { retrofit.getTweets(id) }
+        return safeApiCallRaw { contract.getTweets(id) }
     }
 
     override fun addEvent(cryptoId: String, event: EventEntity): Observable<Response<Void>> {
-        return safeApiCallRaw { retrofit.addEvent(cryptoId, event) }
+        return safeApiCallRaw { contract.addEvent(cryptoId, event) }
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/exchange/ExchangeApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/exchange/ExchangeApi.kt
index ca7da5d..34f208e 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/exchange/ExchangeApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/exchange/ExchangeApi.kt
@@ -1,23 +1,18 @@
 package com.coinpaprika.apiclient.repository.exchange
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.ExchangeEntity
 import com.coinpaprika.apiclient.entity.MarketEntity
 import com.coinpaprika.apiclient.extensions.safeApiCallRaw
 import io.reactivex.Observable
 import retrofit2.Response
 
-class ExchangeApi constructor(
-    private var retrofit: ExchangeApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(ExchangeApiContract::class.java)
-) : ExchangeApiContract {
+class ExchangeApi(private var contract: ExchangeApiContract) : ExchangeApiContract {
 
     override fun getExchanges(): Observable<Response<List<ExchangeEntity>>> {
-        return safeApiCallRaw { retrofit.getExchanges() }
+        return safeApiCallRaw { contract.getExchanges() }
     }
 
     override fun getMarkets(exchangeId: String): Observable<Response<List<MarketEntity>>> {
-        return safeApiCallRaw { retrofit.getMarkets(exchangeId) }
+        return safeApiCallRaw { contract.getMarkets(exchangeId) }
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/fiats/FiatApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/fiats/FiatApi.kt
index f0f90c6..f4baa9d 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/fiats/FiatApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/fiats/FiatApi.kt
@@ -1,15 +1,10 @@
 package com.coinpaprika.apiclient.repository.fiats
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.FiatEntity
 
-class FiatApi constructor(
-    private var retrofit: FiatApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(FiatApiContract::class.java)
-) : FiatApiContract {
+class FiatApi(private var contract: FiatApiContract) : FiatApiContract {
 
     override suspend fun getFiats(): List<FiatEntity> {
-        return retrofit.getFiats()
+        return contract.getFiats()
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/global/GlobalApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/global/GlobalApi.kt
index 62f50a8..83e092e 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/global/GlobalApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/global/GlobalApi.kt
@@ -1,18 +1,13 @@
 package com.coinpaprika.apiclient.repository.global
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.GlobalStatsEntity
 import com.coinpaprika.apiclient.extensions.safeApiCallRaw
 import io.reactivex.Observable
 import retrofit2.Response
 
-class GlobalApi constructor(
-    private var retrofit: GlobalApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(GlobalApiContract::class.java)
-) : GlobalApiContract {
+class GlobalApi(private var contract: GlobalApiContract) : GlobalApiContract {
 
     override fun getGlobal(): Observable<Response<GlobalStatsEntity>> {
-        return safeApiCallRaw { retrofit.getGlobal() }
+        return safeApiCallRaw { contract.getGlobal() }
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/news/NewsApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/news/NewsApi.kt
index 36c2675..17fd336 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/news/NewsApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/news/NewsApi.kt
@@ -1,18 +1,13 @@
 package com.coinpaprika.apiclient.repository.news
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.NewsEntity
 import com.coinpaprika.apiclient.extensions.safeApiCallRaw
 import io.reactivex.Observable
 import retrofit2.Response
 
-class NewsApi constructor(
-    private var retrofit: NewsApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(NewsApiContract::class.java)
-) : NewsApiContract {
+class NewsApi(private var contract: NewsApiContract) : NewsApiContract {
 
     override fun getNews(limit: Int): Observable<Response<List<NewsEntity>>> {
-        return safeApiCallRaw { retrofit.getNews(limit) }
+        return safeApiCallRaw { contract.getNews(limit) }
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/people/PeopleApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/people/PeopleApi.kt
index dbce62e..94fe76e 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/people/PeopleApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/people/PeopleApi.kt
@@ -1,23 +1,18 @@
 package com.coinpaprika.apiclient.repository.people
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.PersonEntity
 import com.coinpaprika.apiclient.entity.TweetEntity
 import com.coinpaprika.apiclient.extensions.safeApiCallRaw
 import io.reactivex.Observable
 import retrofit2.Response
 
-class PeopleApi constructor(
-    private var retrofit: PeopleApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(PeopleApiContract::class.java)
-) : PeopleApiContract {
+class PeopleApi(private var contract: PeopleApiContract) : PeopleApiContract {
 
     override fun getPerson(id: String): Observable<Response<PersonEntity>> {
-        return safeApiCallRaw { retrofit.getPerson(id) }
+        return safeApiCallRaw { contract.getPerson(id) }
     }
 
     override fun getTweets(id: String): Observable<Response<List<TweetEntity>>> {
-        return safeApiCallRaw { retrofit.getTweets(id) }
+        return safeApiCallRaw { contract.getTweets(id) }
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/ranking/RankingApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/ranking/RankingApi.kt
index ff4ffb2..471399f 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/ranking/RankingApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/ranking/RankingApi.kt
@@ -1,19 +1,14 @@
 package com.coinpaprika.apiclient.repository.ranking
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.TopMoversEntity
 
-class RankingApi constructor(
-    private var retrofit: RankingApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(RankingApiContract::class.java)
-) : RankingApiContract {
+class RankingApi(private var contract: RankingApiContract) : RankingApiContract {
 
     override suspend fun getTop10Movers(type: String): TopMoversEntity {
-        return retrofit.getTop10Movers(type)
+        return contract.getTop10Movers(type)
     }
 
     override suspend fun getMovers(results: Int, range: String): TopMoversEntity {
-        return retrofit.getMovers(results, range)
+        return contract.getMovers(results, range)
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/search/SearchApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/search/SearchApi.kt
index e45c0d0..1a54752 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/search/SearchApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/search/SearchApi.kt
@@ -4,16 +4,11 @@
 
 package com.coinpaprika.apiclient.repository.search
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.SearchEntity
 
-class SearchApi constructor(
-    private var retrofit: SearchApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(SearchApiContract::class.java)
-) : SearchApiContract {
+class SearchApi(private var contract: SearchApiContract) : SearchApiContract {
 
     override suspend fun getSearches(query: String): SearchEntity {
-        return retrofit.getSearches(query)
+        return contract.getSearches(query)
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/tag/TagApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/tag/TagApi.kt
index 4b29446..90f63bb 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/tag/TagApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/tag/TagApi.kt
@@ -1,19 +1,14 @@
 package com.coinpaprika.apiclient.repository.tag
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.TagEntity
 
-class TagApi constructor(
-    private var retrofit: TagApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(TagApiContract::class.java)
-) : TagApiContract {
+class TagApi(private var contract: TagApiContract) : TagApiContract {
 
     override suspend fun getTag(id: String): TagEntity {
-        return retrofit.getTag(id)
+        return contract.getTag(id)
     }
 
     override suspend fun getTags(): List<TagEntity> {
-        return retrofit.getTags()
+        return contract.getTags()
     }
 }
\ No newline at end of file
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApi.kt b/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApi.kt
index 5802645..30f535b 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApi.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApi.kt
@@ -1,21 +1,16 @@
 package com.coinpaprika.apiclient.repository.ticker
 
-import com.coinpaprika.apiclient.api.CoinpaprikaApiFactory
 import com.coinpaprika.apiclient.entity.TickerEntity
 import com.coinpaprika.apiclient.extensions.handleCall
 
-class TickerApi {
-
-    private var retrofit: TickerApiContract = CoinpaprikaApiFactory()
-        .client()
-        .create(TickerApiContract::class.java)
+class TickerApi(private val contract: TickerApiContract) {
 
     suspend fun getTicker(id: String, quotes: String? = null): TickerEntity {
         return handleCall {
             if (quotes != null) {
-                retrofit.getTicker(id, quotes)
+                contract.getTicker(id, quotes)
             } else {
-                retrofit.getTicker(id)
+                contract.getTicker(id)
             }
         }
     }
@@ -23,9 +18,9 @@ class TickerApi {
     suspend fun getTickers(quotes: String? = null): List<TickerEntity> {
         return handleCall {
             if (quotes != null) {
-                retrofit.getTickers(quotes)
+                contract.getTickers(quotes)
             } else {
-                retrofit.getTickers()
+                contract.getTickers()
             }
         }
     }
diff --git a/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApiContract.kt b/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApiContract.kt
index 461ccb5..af2aeb9 100644
--- a/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApiContract.kt
+++ b/src/main/java/com/coinpaprika/apiclient/repository/ticker/TickerApiContract.kt
@@ -1,13 +1,12 @@
 package com.coinpaprika.apiclient.repository.ticker
 
 import com.coinpaprika.apiclient.entity.TickerEntity
-import io.reactivex.Observable
 import retrofit2.Response
 import retrofit2.http.GET
 import retrofit2.http.Path
 import retrofit2.http.Query
 
-internal interface TickerApiContract {
+interface TickerApiContract {
     @GET("tickers/{id}/")
     suspend fun getTicker(@Path("id") id: String, @Query("quotes") quotes: String = "USD,BTC,ETH,PLN"): Response<TickerEntity>