diff --git a/build.gradle b/build.gradle
index d4f15101..76d750de 100644
--- a/build.gradle
+++ b/build.gradle
@@ -123,8 +123,16 @@ dependencies {
     implementation(variantOf(libs.netty.tcnative.boringssl) { classifier("linux-x86_64") })
     implementation(variantOf(libs.netty.tcnative.boringssl) { classifier("osx-x86_64") })
     implementation 'dshackle:foundation:1.0.0'
+
+    implementation files('src/main/resources/LogsOracle.jar')
 }
 
+// Enable 'Foreign Function & Memory API' (JEP 434)
+// Drop after update on Java 21
+tasks.withType(JavaCompile) { options.compilerArgs += "--enable-preview" }
+tasks.withType(Test) { jvmArgs += "--enable-preview" }
+tasks.withType(JavaExec) { jvmArgs += "--enable-preview" }
+
 compileKotlin {
     compilerOptions.jvmTarget.set(JvmTarget.JVM_20)
 }
@@ -327,4 +335,4 @@ ktlint {
     }
 }
 
-compileKotlin.dependsOn chainscodegen
\ No newline at end of file
+compileKotlin.dependsOn chainscodegen
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/Config.kt b/src/main/kotlin/io/emeraldpay/dshackle/Config.kt
index b33ab61b..da05fbca 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/Config.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/Config.kt
@@ -21,6 +21,7 @@ import io.emeraldpay.dshackle.config.CacheConfig
 import io.emeraldpay.dshackle.config.ChainsConfig
 import io.emeraldpay.dshackle.config.CompressionConfig
 import io.emeraldpay.dshackle.config.HealthConfig
+import io.emeraldpay.dshackle.config.IndexConfig
 import io.emeraldpay.dshackle.config.MainConfig
 import io.emeraldpay.dshackle.config.MainConfigReader
 import io.emeraldpay.dshackle.config.MonitoringConfig
@@ -130,6 +131,11 @@ open class Config(
         return mainConfig.cache ?: CacheConfig()
     }
 
+    @Bean
+    open fun indexConfig(@Autowired mainConfig: MainConfig): IndexConfig {
+        return mainConfig.index ?: IndexConfig()
+    }
+
     @Bean
     open fun signatureConfig(@Autowired mainConfig: MainConfig): SignatureConfig {
         return mainConfig.signature ?: SignatureConfig()
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/config/IndexConfig.kt b/src/main/kotlin/io/emeraldpay/dshackle/config/IndexConfig.kt
new file mode 100644
index 00000000..00202c6e
--- /dev/null
+++ b/src/main/kotlin/io/emeraldpay/dshackle/config/IndexConfig.kt
@@ -0,0 +1,21 @@
+package io.emeraldpay.dshackle.config
+
+import io.emeraldpay.dshackle.Chain
+
+class IndexConfig {
+    var items: HashMap<Chain, Index> = HashMap<Chain, Index>()
+
+    class Index(
+        var rpc: String,
+        var store: String,
+        var ram_limit: Long?,
+    )
+
+    fun isChainEnabled(chain: Chain): Boolean {
+        return items.containsKey(chain)
+    }
+
+    fun getByChain(chain: Chain): Index? {
+        return items.get(chain)
+    }
+}
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/config/IndexConfigReader.kt b/src/main/kotlin/io/emeraldpay/dshackle/config/IndexConfigReader.kt
new file mode 100644
index 00000000..1297670d
--- /dev/null
+++ b/src/main/kotlin/io/emeraldpay/dshackle/config/IndexConfigReader.kt
@@ -0,0 +1,62 @@
+package io.emeraldpay.dshackle.config
+
+import io.emeraldpay.dshackle.Chain
+import io.emeraldpay.dshackle.Global
+import io.emeraldpay.dshackle.foundation.YamlConfigReader
+import org.apache.commons.lang3.StringUtils
+import org.slf4j.LoggerFactory
+import org.springframework.util.unit.DataSize
+import org.yaml.snakeyaml.nodes.MappingNode
+
+class IndexConfigReader : YamlConfigReader<IndexConfig>() {
+
+    companion object {
+        private val log = LoggerFactory.getLogger(IndexConfigReader::class.java)
+    }
+
+    override fun read(input: MappingNode?): IndexConfig? {
+        return getList<MappingNode>(input, "index")?.let { items ->
+            val config = IndexConfig()
+
+            items.value.map {
+                val blockchainRaw = getValueAsString(it, "chain")
+                if (blockchainRaw == null || StringUtils.isEmpty(blockchainRaw) || Global.chainById(blockchainRaw) == Chain.UNSPECIFIED) {
+                    throw InvalidConfigYamlException(filename, it.startMark, "Invalid blockchain or not specified")
+                }
+
+                val blockchain = Global.chainById(blockchainRaw)
+                if (config.items.containsKey(blockchain)) {
+                    throw InvalidConfigYamlException(filename, it.startMark, "Duplicated indexes")
+                }
+
+                val rpc = getValueAsString(it, "rpc")
+                if (rpc == null || StringUtils.isEmpty(rpc)) {
+                    throw InvalidConfigYamlException(filename, it.startMark, "Invalid rpc specified")
+                }
+
+                val store = getValueAsString(it, "store")
+                if (store == null || StringUtils.isEmpty(store)) {
+                    throw InvalidConfigYamlException(filename, it.startMark, "Invalid store directory or not specified")
+                }
+
+                val limit = getMapping(it, "limit")
+                val ram_limit = limit?.let {
+                    val raw = getValueAsString(limit, "ram")
+                    if (raw == null || StringUtils.isEmpty(raw)) {
+                        return null
+                    }
+
+                    try {
+                        DataSize.parse(raw).toBytes()
+                    } catch (e: IllegalArgumentException) {
+                        throw InvalidConfigYamlException(filename, it.startMark, "Invalid limit for index")
+                    }
+                }
+
+                config.items.put(blockchain, IndexConfig.Index(rpc, store, ram_limit))
+            }
+
+            config
+        }
+    }
+}
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfig.kt b/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfig.kt
index 9d6b125a..9146b376 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfig.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfig.kt
@@ -21,6 +21,7 @@ class MainConfig {
     var tls: AuthConfig.ServerTlsAuth? = null
     var passthrough: Boolean = false
     var cache: CacheConfig? = null
+    var index: IndexConfig? = null
     var proxy: ProxyConfig? = null
     var upstreams: UpstreamsConfig? = null
     var tokens: TokensConfig? = null
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfigReader.kt b/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfigReader.kt
index 90cdef65..7522c562 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfigReader.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/config/MainConfigReader.kt
@@ -29,6 +29,7 @@ class MainConfigReader(
     private val optionsReader = ChainOptionsReader()
     private val upstreamsConfigReader = UpstreamsConfigReader(fileResolver, optionsReader)
     private val cacheConfigReader = CacheConfigReader()
+    private val indexConfigReader = IndexConfigReader()
     private val tokensConfigReader = TokensConfigReader()
     private val monitoringConfigReader = MonitoringConfigReader()
     private val accessLogReader = AccessLogReader()
@@ -63,6 +64,9 @@ class MainConfigReader(
         cacheConfigReader.read(input)?.let {
             config.cache = it
         }
+        indexConfigReader.read(input)?.let {
+            config.index = it
+        }
         tokensConfigReader.read(input)?.let {
             config.tokens = it
         }
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/config/context/MultistreamsConfig.kt b/src/main/kotlin/io/emeraldpay/dshackle/config/context/MultistreamsConfig.kt
index daa38e6a..dc0a299d 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/config/context/MultistreamsConfig.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/config/context/MultistreamsConfig.kt
@@ -3,6 +3,7 @@ package io.emeraldpay.dshackle.config.context
 import io.emeraldpay.dshackle.BlockchainType.BITCOIN
 import io.emeraldpay.dshackle.Chain
 import io.emeraldpay.dshackle.cache.CachesFactory
+import io.emeraldpay.dshackle.config.IndexConfig
 import io.emeraldpay.dshackle.upstream.CallTargetsHolder
 import io.emeraldpay.dshackle.upstream.Multistream
 import io.emeraldpay.dshackle.upstream.bitcoin.BitcoinMultistream
@@ -26,6 +27,9 @@ open class MultistreamsConfig(val beanFactory: ConfigurableListableBeanFactory)
         headScheduler: Scheduler,
         tracer: Tracer,
         multistreamEventsScheduler: Scheduler,
+        indexConfig: IndexConfig,
+        @Qualifier("logsOracleScheduler")
+        logsOracleScheduler: Scheduler,
     ): List<Multistream> {
         return Chain.entries
             .filterNot { it == Chain.UNSPECIFIED }
@@ -33,7 +37,15 @@ open class MultistreamsConfig(val beanFactory: ConfigurableListableBeanFactory)
                 if (chain.type == BITCOIN) {
                     bitcoinMultistream(chain, cachesFactory, headScheduler, multistreamEventsScheduler)
                 } else {
-                    genericMultistream(chain, cachesFactory, headScheduler, tracer, multistreamEventsScheduler)
+                    genericMultistream(
+                        chain,
+                        cachesFactory,
+                        headScheduler,
+                        tracer,
+                        multistreamEventsScheduler,
+                        indexConfig.getByChain(chain),
+                        logsOracleScheduler,
+                    )
                 }
             }
     }
@@ -44,6 +56,8 @@ open class MultistreamsConfig(val beanFactory: ConfigurableListableBeanFactory)
         headScheduler: Scheduler,
         tracer: Tracer,
         multistreamEventsScheduler: Scheduler,
+        logsOracleConfig: IndexConfig.Index?,
+        logsOracleScheduler: Scheduler,
     ): Multistream {
         val name = "multi-$chain"
         val cs = ChainSpecificRegistry.resolve(chain)
@@ -58,6 +72,8 @@ open class MultistreamsConfig(val beanFactory: ConfigurableListableBeanFactory)
             cs.makeCachingReaderBuilder(tracer),
             cs::localReaderBuilder,
             cs.subscriptionBuilder(headScheduler),
+            logsOracleConfig,
+            logsOracleScheduler,
         ).also { register(it, name) }
     }
 
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/config/context/SchedulersConfig.kt b/src/main/kotlin/io/emeraldpay/dshackle/config/context/SchedulersConfig.kt
index ac2892e9..a5383564 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/config/context/SchedulersConfig.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/config/context/SchedulersConfig.kt
@@ -30,6 +30,11 @@ open class SchedulersConfig {
         return makeScheduler("head-scheduler", 4, monitoringConfig)
     }
 
+    @Bean
+    open fun logsOracleScheduler(monitoringConfig: MonitoringConfig): Scheduler {
+        return makeScheduler("logs-oracle", 4, monitoringConfig)
+    }
+
     @Bean
     open fun multistreamEventsScheduler(monitoringConfig: MonitoringConfig): Scheduler {
         return makeScheduler("events-scheduler", 4, monitoringConfig)
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/BitcoinUpstreamCreator.kt b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/BitcoinUpstreamCreator.kt
index c6c5ccc3..4836420e 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/BitcoinUpstreamCreator.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/BitcoinUpstreamCreator.kt
@@ -3,6 +3,7 @@ package io.emeraldpay.dshackle.startup.configure
 import io.emeraldpay.dshackle.Chain
 import io.emeraldpay.dshackle.FileResolver
 import io.emeraldpay.dshackle.config.ChainsConfig
+import io.emeraldpay.dshackle.config.IndexConfig
 import io.emeraldpay.dshackle.config.UpstreamsConfig
 import io.emeraldpay.dshackle.foundation.ChainOptions
 import io.emeraldpay.dshackle.startup.QuorumForLabels
@@ -24,11 +25,12 @@ import java.util.concurrent.atomic.AtomicInteger
 @Component
 class BitcoinUpstreamCreator(
     chainsConfig: ChainsConfig,
+    indexConfig: IndexConfig,
     callTargets: CallTargetsHolder,
     private val genericConnectorFactoryCreator: ConnectorFactoryCreator,
     private val fileResolver: FileResolver,
     private val headScheduler: Scheduler,
-) : UpstreamCreator(chainsConfig, callTargets) {
+) : UpstreamCreator(chainsConfig, indexConfig, callTargets) {
     private var seq = AtomicInteger(0)
 
     override fun createUpstream(
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/EthereumUpstreamCreator.kt b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/EthereumUpstreamCreator.kt
index 3f653db8..211a9219 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/EthereumUpstreamCreator.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/EthereumUpstreamCreator.kt
@@ -2,6 +2,7 @@ package io.emeraldpay.dshackle.startup.configure
 
 import io.emeraldpay.dshackle.Chain
 import io.emeraldpay.dshackle.config.ChainsConfig
+import io.emeraldpay.dshackle.config.IndexConfig
 import io.emeraldpay.dshackle.config.UpstreamsConfig
 import io.emeraldpay.dshackle.foundation.ChainOptions
 import io.emeraldpay.dshackle.upstream.CallTargetsHolder
@@ -11,9 +12,10 @@ import org.springframework.stereotype.Component
 @Component
 class EthereumUpstreamCreator(
     chainsConfig: ChainsConfig,
+    indexConfig: IndexConfig,
     callTargets: CallTargetsHolder,
     genericConnectorFactoryCreator: ConnectorFactoryCreator,
-) : GenericUpstreamCreator(chainsConfig, callTargets, genericConnectorFactoryCreator) {
+) : GenericUpstreamCreator(chainsConfig, indexConfig, callTargets, genericConnectorFactoryCreator) {
 
     override fun createUpstream(
         upstreamsConfig: UpstreamsConfig.Upstream<*>,
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/GenericUpstreamCreator.kt b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/GenericUpstreamCreator.kt
index 9d13939a..eff68248 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/GenericUpstreamCreator.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/GenericUpstreamCreator.kt
@@ -2,6 +2,7 @@ package io.emeraldpay.dshackle.startup.configure
 
 import io.emeraldpay.dshackle.Chain
 import io.emeraldpay.dshackle.config.ChainsConfig
+import io.emeraldpay.dshackle.config.IndexConfig
 import io.emeraldpay.dshackle.config.UpstreamsConfig
 import io.emeraldpay.dshackle.foundation.ChainOptions
 import io.emeraldpay.dshackle.startup.QuorumForLabels
@@ -19,9 +20,10 @@ import kotlin.math.abs
 @Component
 open class GenericUpstreamCreator(
     chainsConfig: ChainsConfig,
+    indexConfig: IndexConfig,
     callTargets: CallTargetsHolder,
     private val genericConnectorFactoryCreator: ConnectorFactoryCreator,
-) : UpstreamCreator(chainsConfig, callTargets) {
+) : UpstreamCreator(chainsConfig, indexConfig, callTargets) {
     private val hashes: MutableMap<Byte, Boolean> = HashMap()
 
     override fun createUpstream(
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/UpstreamCreator.kt b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/UpstreamCreator.kt
index 8eba6746..786b9a88 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/UpstreamCreator.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/startup/configure/UpstreamCreator.kt
@@ -3,6 +3,7 @@ package io.emeraldpay.dshackle.startup.configure
 import io.emeraldpay.dshackle.Chain
 import io.emeraldpay.dshackle.Global
 import io.emeraldpay.dshackle.config.ChainsConfig
+import io.emeraldpay.dshackle.config.IndexConfig
 import io.emeraldpay.dshackle.config.UpstreamsConfig
 import io.emeraldpay.dshackle.foundation.ChainOptions
 import io.emeraldpay.dshackle.upstream.CallTargetsHolder
@@ -14,6 +15,7 @@ import org.slf4j.LoggerFactory
 
 abstract class UpstreamCreator(
     private val chainsConfig: ChainsConfig,
+    private val indexConfig: IndexConfig,
     private val callTargets: CallTargetsHolder,
 ) {
     protected val log: Logger = LoggerFactory.getLogger(this::class.java)
@@ -45,7 +47,7 @@ abstract class UpstreamCreator(
     protected fun buildMethods(config: UpstreamsConfig.Upstream<*>, chain: Chain): CallMethods {
         return if (config.methods != null || config.methodGroups != null) {
             ManagedCallMethods(
-                delegate = callTargets.getDefaultMethods(chain),
+                delegate = callTargets.getDefaultMethods(chain, indexConfig.isChainEnabled(chain)),
                 enabled = config.methods?.enabled?.map { it.name }?.toSet() ?: emptySet(),
                 disabled = config.methods?.disabled?.map { it.name }?.toSet() ?: emptySet(),
                 groupsEnabled = config.methodGroups?.enabled ?: emptySet(),
@@ -61,7 +63,7 @@ abstract class UpstreamCreator(
                 }
             }
         } else {
-            callTargets.getDefaultMethods(chain)
+            callTargets.getDefaultMethods(chain, indexConfig.isChainEnabled(chain))
         }
     }
 }
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/CallTargetsHolder.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/CallTargetsHolder.kt
index 3f2e51af..56bddb33 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/CallTargetsHolder.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/CallTargetsHolder.kt
@@ -18,14 +18,14 @@ import org.springframework.stereotype.Component
 class CallTargetsHolder {
     private val callTargets = HashMap<Chain, CallMethods>()
 
-    fun getDefaultMethods(chain: Chain): CallMethods {
-        return callTargets[chain] ?: return setupDefaultMethods(chain)
+    fun getDefaultMethods(chain: Chain, hasLogsOracle: Boolean): CallMethods {
+        return callTargets[chain] ?: return setupDefaultMethods(chain, hasLogsOracle)
     }
 
-    private fun setupDefaultMethods(chain: Chain): CallMethods {
+    private fun setupDefaultMethods(chain: Chain, hasLogsOracle: Boolean): CallMethods {
         val created = when (chain.type) {
             BITCOIN -> DefaultBitcoinMethods()
-            ETHEREUM -> DefaultEthereumMethods(chain)
+            ETHEREUM -> DefaultEthereumMethods(chain, hasLogsOracle)
             STARKNET -> DefaultStarknetMethods(chain)
             POLKADOT -> DefaultPolkadotMethods()
             SOLANA -> DefaultSolanaMethods()
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/LogsOracle.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/LogsOracle.kt
new file mode 100644
index 00000000..5a14f9d3
--- /dev/null
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/LogsOracle.kt
@@ -0,0 +1,42 @@
+package io.emeraldpay.dshackle.upstream
+
+import io.emeraldpay.dshackle.config.IndexConfig
+import org.slf4j.LoggerFactory
+import reactor.core.Disposable
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Scheduler
+
+class LogsOracle(
+    private val config: IndexConfig.Index,
+    private val upstream: Multistream,
+    private val scheduler: Scheduler,
+) {
+
+    private val log = LoggerFactory.getLogger(LogsOracle::class.java)
+
+    private var subscription: Disposable? = null
+    private val db = org.drpc.logsoracle.LogsOracle(config.store, config.store, config.ram_limit ?: 0L)
+
+    fun start() {
+        subscription = upstream.getHead().getFlux()
+            .doOnError { t -> log.warn("Failed to subscribe head for oracle", t) }
+            .subscribe { println(it.height); db.UpdateHeight(it.height) }
+    }
+
+    fun stop() {
+        db.close()
+
+        subscription?.dispose()
+        subscription = null
+    }
+
+    fun estimate(
+        fromBlock: Long?,
+        toBlock: Long?,
+        address: List<String>,
+        topics: List<List<String>>,
+    ): Mono<Long> {
+        return Mono.fromCallable { db.Query(fromBlock, toBlock, address, topics) }
+            .subscribeOn(scheduler)
+    }
+}
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethods.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethods.kt
index 2f52c9c3..885b90ea 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethods.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethods.kt
@@ -32,6 +32,7 @@ import io.emeraldpay.etherjar.rpc.RpcException
  */
 class DefaultEthereumMethods(
     private val chain: Chain,
+    private val hasLogsOracle: Boolean = false,
 ) : CallMethods {
 
     private val version = "\"EmeraldDshackle/${Global.version}\""
@@ -137,6 +138,7 @@ class DefaultEthereumMethods(
             specialMethods +
             headVerifiedMethods -
             chainUnsupportedMethods(chain) +
+            getDrpcVendorMethods(chain) +
             getChainSpecificMethods(chain)
     }
 
@@ -148,6 +150,7 @@ class DefaultEthereumMethods(
             firstValueMethods.contains(method) -> AlwaysQuorum()
             anyResponseMethods.contains(method) -> NotLaggingQuorum(4)
             headVerifiedMethods.contains(method) -> NotLaggingQuorum(1)
+            getDrpcVendorMethods(chain).contains(method) -> AlwaysQuorum()
             possibleNotIndexedMethods.contains(method) -> NotNullQuorum()
             specialMethods.contains(method) -> {
                 when (method) {
@@ -174,6 +177,15 @@ class DefaultEthereumMethods(
         }
     }
 
+    private fun getDrpcVendorMethods(chain: Chain): List<String> {
+        val supported = mutableListOf<String>()
+
+        // Currently tested on eth mainnet only, should potentially work for all compatible ones.
+        if (chain == Chain.ETHEREUM__MAINNET && hasLogsOracle) { supported.add("drpc_getLogsEstimate") }
+
+        return supported
+    }
+
     private fun getChainSpecificMethods(chain: Chain): List<String> {
         return when (chain) {
             Chain.OPTIMISM__MAINNET, Chain.OPTIMISM__GOERLI -> listOf(
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumChainSpecific.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumChainSpecific.kt
index 648d9dd7..58201b99 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumChainSpecific.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumChainSpecific.kt
@@ -11,6 +11,7 @@ import io.emeraldpay.dshackle.upstream.EgressSubscription
 import io.emeraldpay.dshackle.upstream.Head
 import io.emeraldpay.dshackle.upstream.IngressSubscription
 import io.emeraldpay.dshackle.upstream.LabelsDetector
+import io.emeraldpay.dshackle.upstream.LogsOracle
 import io.emeraldpay.dshackle.upstream.Multistream
 import io.emeraldpay.dshackle.upstream.Upstream
 import io.emeraldpay.dshackle.upstream.UpstreamValidator
@@ -48,8 +49,9 @@ object EthereumChainSpecific : AbstractPollChainSpecific() {
         cachingReader: CachingReader,
         methods: CallMethods,
         head: Head,
+        logsOracle: LogsOracle?,
     ): Mono<JsonRpcReader> {
-        return Mono.just(EthereumLocalReader(cachingReader as EthereumCachingReader, methods, head))
+        return Mono.just(EthereumLocalReader(cachingReader as EthereumCachingReader, methods, head, logsOracle))
     }
 
     override fun subscriptionBuilder(headScheduler: Scheduler): (Multistream) -> EgressSubscription {
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReader.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReader.kt
index 26212358..24c4a2cb 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReader.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReader.kt
@@ -20,6 +20,7 @@ import io.emeraldpay.dshackle.data.BlockId
 import io.emeraldpay.dshackle.data.TxId
 import io.emeraldpay.dshackle.reader.JsonRpcReader
 import io.emeraldpay.dshackle.upstream.Head
+import io.emeraldpay.dshackle.upstream.LogsOracle
 import io.emeraldpay.dshackle.upstream.calls.CallMethods
 import io.emeraldpay.dshackle.upstream.rpcclient.JsonRpcRequest
 import io.emeraldpay.dshackle.upstream.rpcclient.JsonRpcResponse
@@ -41,6 +42,7 @@ class EthereumLocalReader(
     private val reader: EthereumCachingReader,
     private val methods: CallMethods,
     private val head: Head,
+    private val logsOracle: LogsOracle?,
 ) : JsonRpcReader {
 
     override fun read(key: JsonRpcRequest): Mono<JsonRpcResponse> {
@@ -120,6 +122,9 @@ class EthereumLocalReader(
                     .read(hash)
                     .map { it.data to it.upstreamId }
             }
+            method == "drpc_getLogsEstimate" -> {
+                getLogsEstimate(params)
+            }
             else -> null
         }
     }
@@ -167,4 +172,82 @@ class EthereumLocalReader(
         return reader.blocksByHeightAsCont()
             .read(number).map { it.data.json!! to it.upstreamId }
     }
+
+    fun getLogsEstimate(params: List<Any?>): Mono<Pair<ByteArray, String?>>? {
+        if (logsOracle == null) {
+            throw NotImplementedError()
+        }
+        if (params.size != 1 || params[0] == null) {
+            throw RpcException(RpcResponseError.CODE_INVALID_METHOD_PARAMS, "Must provide 1 parameters")
+        }
+
+        val req = params[0] as LinkedHashMap<String, Any?>
+
+        val fromBlock = try { parseBlockRef(req.get("fromBlock") as String?) } catch (_: IllegalArgumentException) {
+            throw RpcException(RpcResponseError.CODE_INVALID_METHOD_PARAMS, "Invalid 'fromBlock' parameter")
+        }
+        val toBlock = try { parseBlockRef(req.get("toBlock") as String?) } catch (_: IllegalArgumentException) {
+            throw RpcException(RpcResponseError.CODE_INVALID_METHOD_PARAMS, "Invalid 'toBlock' parameter")
+        }
+        val address: List<String> = try {
+            val it = req.get("address") ?: listOf<String>()
+
+            if (it is String) {
+                listOf<String>(it)
+            } else {
+                it as List<String>
+            }
+        } catch (_: Exception) {
+            throw RpcException(RpcResponseError.CODE_INVALID_METHOD_PARAMS, "Invalid 'address' parameter")
+        }
+        val topics: List<List<String>> = try {
+            val tpcs = req.get("topics")?.let { it as List<Any> } ?: listOf<Any>()
+            if (tpcs.size > 4) {
+                throw IllegalArgumentException()
+            }
+
+            tpcs.map {
+                if (it is String) {
+                    listOf<String>(it)
+                } else {
+                    it as List<String>
+                }
+            }
+        } catch (_: Exception) {
+            throw RpcException(RpcResponseError.CODE_INVALID_METHOD_PARAMS, "Invalid 'topics' parameter")
+        }
+
+        return logsOracle.estimate(fromBlock, toBlock, address, topics)
+            .map { it.toString().toByteArray() to null }
+    }
+
+    private fun parseBlockRef(blockRef: String?): Long? {
+        when {
+            blockRef == null -> {
+                return null
+            }
+            blockRef == "latest" -> {
+                return head.getCurrentHeight() ?: return null
+            }
+            blockRef == "earliest" -> {
+                return 0
+            }
+            blockRef == "finalized" || blockRef == "safe" || blockRef == "pending" -> {
+                return null
+            }
+            blockRef.startsWith("0x") -> {
+                val quantity = HexQuantity.from(blockRef) ?: throw IllegalArgumentException()
+                return quantity.value.let {
+                    if (it < BigInteger.valueOf(Long.MAX_VALUE) && it >= BigInteger.ZERO) {
+                        it.toLong()
+                    } else {
+                        throw IllegalArgumentException()
+                    }
+                }
+            }
+            else -> {
+                throw IllegalArgumentException()
+            }
+        }
+    }
 }
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/AbstractChainSpecific.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/AbstractChainSpecific.kt
index 840e2477..fba52c94 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/AbstractChainSpecific.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/AbstractChainSpecific.kt
@@ -12,6 +12,7 @@ import io.emeraldpay.dshackle.upstream.EmptyEgressSubscription
 import io.emeraldpay.dshackle.upstream.Head
 import io.emeraldpay.dshackle.upstream.IngressSubscription
 import io.emeraldpay.dshackle.upstream.LabelsDetector
+import io.emeraldpay.dshackle.upstream.LogsOracle
 import io.emeraldpay.dshackle.upstream.Multistream
 import io.emeraldpay.dshackle.upstream.NoIngressSubscription
 import io.emeraldpay.dshackle.upstream.NoopCachingReader
@@ -31,6 +32,7 @@ abstract class AbstractChainSpecific : ChainSpecific {
         cachingReader: CachingReader,
         methods: CallMethods,
         head: Head,
+        logsOracle: LogsOracle?,
     ): Mono<JsonRpcReader> {
         return Mono.just(LocalReader(methods))
     }
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/ChainSpecific.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/ChainSpecific.kt
index c613c88a..9249f660 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/ChainSpecific.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/ChainSpecific.kt
@@ -17,6 +17,7 @@ import io.emeraldpay.dshackle.upstream.EgressSubscription
 import io.emeraldpay.dshackle.upstream.Head
 import io.emeraldpay.dshackle.upstream.IngressSubscription
 import io.emeraldpay.dshackle.upstream.LabelsDetector
+import io.emeraldpay.dshackle.upstream.LogsOracle
 import io.emeraldpay.dshackle.upstream.Multistream
 import io.emeraldpay.dshackle.upstream.Upstream
 import io.emeraldpay.dshackle.upstream.UpstreamValidator
@@ -34,7 +35,7 @@ import reactor.core.publisher.Mono
 import reactor.core.scheduler.Scheduler
 
 typealias SubscriptionBuilder = (Multistream) -> EgressSubscription
-typealias LocalReaderBuilder = (CachingReader, CallMethods, Head) -> Mono<JsonRpcReader>
+typealias LocalReaderBuilder = (CachingReader, CallMethods, Head, LogsOracle?) -> Mono<JsonRpcReader>
 typealias CachingReaderBuilder = (Multistream, Caches, Factory<CallMethods>) -> CachingReader
 
 interface ChainSpecific {
@@ -46,7 +47,7 @@ interface ChainSpecific {
 
     fun unsubscribeNewHeadsRequest(subId: String): JsonRpcRequest
 
-    fun localReaderBuilder(cachingReader: CachingReader, methods: CallMethods, head: Head): Mono<JsonRpcReader>
+    fun localReaderBuilder(cachingReader: CachingReader, methods: CallMethods, head: Head, logsOracle: LogsOracle?): Mono<JsonRpcReader>
 
     fun subscriptionBuilder(headScheduler: Scheduler): (Multistream) -> EgressSubscription
 
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/GenericMultistream.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/GenericMultistream.kt
index 5e9b03e8..c83cf6bc 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/GenericMultistream.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/generic/GenericMultistream.kt
@@ -19,6 +19,7 @@ package io.emeraldpay.dshackle.upstream.generic
 import io.emeraldpay.api.proto.BlockchainOuterClass
 import io.emeraldpay.dshackle.Chain
 import io.emeraldpay.dshackle.cache.Caches
+import io.emeraldpay.dshackle.config.IndexConfig
 import io.emeraldpay.dshackle.config.UpstreamsConfig
 import io.emeraldpay.dshackle.data.BlockContainer
 import io.emeraldpay.dshackle.reader.JsonRpcReader
@@ -31,6 +32,7 @@ import io.emeraldpay.dshackle.upstream.EmptyHead
 import io.emeraldpay.dshackle.upstream.Head
 import io.emeraldpay.dshackle.upstream.HeadLagObserver
 import io.emeraldpay.dshackle.upstream.Lifecycle
+import io.emeraldpay.dshackle.upstream.LogsOracle
 import io.emeraldpay.dshackle.upstream.MergedHead
 import io.emeraldpay.dshackle.upstream.Multistream
 import io.emeraldpay.dshackle.upstream.Selector
@@ -58,6 +60,8 @@ open class GenericMultistream(
     cachingReaderBuilder: CachingReaderBuilder,
     private val localReaderBuilder: LocalReaderBuilder,
     private val subscriptionBuilder: SubscriptionBuilder,
+    logsOracleConfig: IndexConfig.Index? = null,
+    private val logsOracleScheduler: Scheduler,
 ) : Multistream(chain, caches, callSelector, multistreamEventsScheduler) {
 
     private val cachingReader = cachingReaderBuilder(this, caches, getMethodsFactory())
@@ -76,6 +80,10 @@ open class GenericMultistream(
         headScheduler,
     )
 
+    private val logsOracle: LogsOracle? = logsOracleConfig?.let {
+        LogsOracle(logsOracleConfig, this, logsOracleScheduler)
+    }
+
     private var subscription: EgressSubscription = subscriptionBuilder(this)
 
     private val filteredHeads: MutableMap<String, Head> =
@@ -86,12 +94,14 @@ open class GenericMultistream(
         head.start()
         onHeadUpdated(head)
         cachingReader.start()
+        logsOracle?.start()
     }
 
     override fun stop() {
         super.stop()
         cachingReader.stop()
         filteredHeads.clear()
+        logsOracle?.stop()
     }
 
     override fun addHead(upstream: Upstream) {
@@ -181,7 +191,7 @@ open class GenericMultistream(
     }
 
     override fun getLocalReader(): Mono<JsonRpcReader> {
-        return localReaderBuilder(cachingReader, getMethods(), getHead())
+        return localReaderBuilder(cachingReader, getMethods(), getHead(), logsOracle)
     }
 
     override fun getEgressSubscription(): EgressSubscription {
diff --git a/src/main/kotlin/io/emeraldpay/dshackle/upstream/polkadot/PolkadotChainSpecific.kt b/src/main/kotlin/io/emeraldpay/dshackle/upstream/polkadot/PolkadotChainSpecific.kt
index 48d05ae9..1bdb96d5 100644
--- a/src/main/kotlin/io/emeraldpay/dshackle/upstream/polkadot/PolkadotChainSpecific.kt
+++ b/src/main/kotlin/io/emeraldpay/dshackle/upstream/polkadot/PolkadotChainSpecific.kt
@@ -14,6 +14,7 @@ import io.emeraldpay.dshackle.upstream.EgressSubscription
 import io.emeraldpay.dshackle.upstream.Head
 import io.emeraldpay.dshackle.upstream.IngressSubscription
 import io.emeraldpay.dshackle.upstream.LabelsDetector
+import io.emeraldpay.dshackle.upstream.LogsOracle
 import io.emeraldpay.dshackle.upstream.Multistream
 import io.emeraldpay.dshackle.upstream.NoopCachingReader
 import io.emeraldpay.dshackle.upstream.Upstream
@@ -74,6 +75,7 @@ object PolkadotChainSpecific : AbstractPollChainSpecific() {
         cachingReader: CachingReader,
         methods: CallMethods,
         head: Head,
+        logsOracle: LogsOracle?,
     ): Mono<JsonRpcReader> {
         return Mono.just(LocalReader(methods))
     }
diff --git a/src/main/resources/LogsOracle.jar b/src/main/resources/LogsOracle.jar
new file mode 100644
index 00000000..7194f50d
Binary files /dev/null and b/src/main/resources/LogsOracle.jar differ
diff --git a/src/test/groovy/io/emeraldpay/dshackle/rpc/NativeCallSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/rpc/NativeCallSpec.groovy
index 06fb63bb..04e36064 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/rpc/NativeCallSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/rpc/NativeCallSpec.groovy
@@ -398,7 +398,7 @@ class NativeCallSpec extends Specification {
     def "Prepare call adds height selector for not-lagging quorum"() {
         setup:
         def methods = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 ["foo_bar"] as Set, [] as Set, [] as Set, [] as Set
         )
         methods.setQuorum("foo_bar", "not_lagging")
@@ -439,7 +439,7 @@ class NativeCallSpec extends Specification {
     def "Prepare call adds decorator for eth_newFilter"() {
         setup:
         def methods = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 ["eth_newFilter"] as Set, [] as Set, [] as Set, [] as Set
         )
         methods.setQuorum("eth_newFilter", "always")
@@ -470,7 +470,7 @@ class NativeCallSpec extends Specification {
     def "Prepare call adds decorator for eth_getFilterChanges"() {
         setup:
         def methods = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 ["eth_getFilterChanges"] as Set, [] as Set, [] as Set, [] as Set
         )
         def multistream = new MultistreamHolderMock.EthereumMultistreamMock(Chain.ETHEREUM__MAINNET, TestingCommons.upstream())
@@ -500,7 +500,7 @@ class NativeCallSpec extends Specification {
     def "Prepare call adds decorator for eth_uninstallFilter"() {
         setup:
         def methods = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 ["eth_uninstallFilter"] as Set, [] as Set, [] as Set, [] as Set
         )
         def multistream = new MultistreamHolderMock.EthereumMultistreamMock(Chain.ETHEREUM__MAINNET, TestingCommons.upstream())
@@ -600,7 +600,7 @@ class NativeCallSpec extends Specification {
         }
         def quorum = new AlwaysQuorum()
         def methods = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 [] as Set, [] as Set, ["filter"] as Set, [] as Set
         )
         def multistream = new MultistreamHolderMock.EthereumMultistreamMock(Chain.ETHEREUM__MAINNET, new ArrayList<GenericUpstream>())
@@ -636,7 +636,7 @@ class NativeCallSpec extends Specification {
         }
         def quorum = new AlwaysQuorum()
         def methods = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 [] as Set, [] as Set, ["filter"] as Set, [] as Set
         )
         def multistream = new MultistreamHolderMock.EthereumMultistreamMock(Chain.ETHEREUM__MAINNET, new ArrayList<GenericUpstream>())
diff --git a/src/test/groovy/io/emeraldpay/dshackle/test/GenericUpstreamMock.groovy b/src/test/groovy/io/emeraldpay/dshackle/test/GenericUpstreamMock.groovy
index 56da1932..1ce79a88 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/test/GenericUpstreamMock.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/test/GenericUpstreamMock.groovy
@@ -36,7 +36,7 @@ class GenericUpstreamMock extends GenericUpstream {
 
     static CallMethods allMethods() {
         new AggregatedCallMethods([
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 new DefaultBitcoinMethods(),
                 new DirectCallMethods(["eth_test"])
         ])
diff --git a/src/test/groovy/io/emeraldpay/dshackle/test/MultistreamHolderMock.groovy b/src/test/groovy/io/emeraldpay/dshackle/test/MultistreamHolderMock.groovy
index 5cf1e836..d88a8403 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/test/MultistreamHolderMock.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/test/MultistreamHolderMock.groovy
@@ -51,7 +51,8 @@ class MultistreamHolderMock implements MultistreamHolder {
                             Schedulers.boundedElastic(),
                             EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(TestingCommons.tracerMock()),
                             EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                            io.emeraldpay.dshackle.upstream.starknet.StarknetChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic())
+                            io.emeraldpay.dshackle.upstream.starknet.StarknetChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()),
+                            null, Schedulers.immediate()
                     )
                     upstreams[chain].addUpstream(up)
                 } else {
@@ -104,7 +105,7 @@ class MultistreamHolderMock implements MultistreamHolder {
             super(chain, Schedulers.immediate(), null, upstreams, caches, Schedulers.boundedElastic(),
                     EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(new BraveTracer(null, null, null)),
                     EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                    EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                    EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()), null, Schedulers.immediate())
         }
 
         EthereumMultistreamMock(@NotNull Chain chain, @NotNull List<GenericUpstream> upstreams) {
diff --git a/src/test/groovy/io/emeraldpay/dshackle/test/TestingCommons.groovy b/src/test/groovy/io/emeraldpay/dshackle/test/TestingCommons.groovy
index 3afa1302..288cddf2 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/test/TestingCommons.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/test/TestingCommons.groovy
@@ -98,6 +98,8 @@ class TestingCommons {
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
                 EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()),
+                null,
+                Schedulers.immediate()
         ).tap {
             it.processUpstreamsEvents(
                     new UpstreamChangeEvent(Chain.ETHEREUM__MAINNET, up, UpstreamChangeEvent.ChangeType.ADDED)
@@ -124,14 +126,18 @@ class TestingCommons {
         return new GenericMultistream(chain, Schedulers.immediate(), null, [], emptyCaches().getCaches(chain), Schedulers.boundedElastic(),
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()),
+                null,
+                Schedulers.immediate())
     }
 
     static Multistream multistreamClassicWithoutUpstreams(Chain chain) {
         return new GenericMultistream(chain, Schedulers.immediate(), null, [], emptyCaches().getCaches(chain), Schedulers.boundedElastic(),
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()),
+                null,
+                Schedulers.immediate())
     }
 
     static FileResolver fileResolver() {
diff --git a/src/test/groovy/io/emeraldpay/dshackle/upstream/FilteredApisSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/upstream/FilteredApisSpec.groovy
index 3a629d4e..056993a7 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/upstream/FilteredApisSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/upstream/FilteredApisSpec.groovy
@@ -39,7 +39,7 @@ import static java.util.List.of
 
 class FilteredApisSpec extends Specification {
 
-    def ethereumTargets = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+    def ethereumTargets = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
 
     def "Verifies labels"() {
         setup:
diff --git a/src/test/groovy/io/emeraldpay/dshackle/upstream/MultistreamSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/upstream/MultistreamSpec.groovy
index c57129eb..594b00c7 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/upstream/MultistreamSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/upstream/MultistreamSpec.groovy
@@ -59,7 +59,7 @@ class MultistreamSpec extends Specification {
                 Schedulers.boundedElastic(),
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(TestingCommons.tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()), null, Schedulers.immediate())
         when:
         aggr.onUpstreamsUpdated()
         def act = aggr.getMethods()
@@ -194,7 +194,7 @@ class MultistreamSpec extends Specification {
                 Schedulers.boundedElastic(),
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(TestingCommons.tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()), null, Schedulers.immediate())
 
         expect:
         multistream.getHead(new Selector.LabelMatcher("provider", ["internal"])).is(up1.ethereumHeadMock)
@@ -267,7 +267,7 @@ class MultistreamSpec extends Specification {
                 Schedulers.boundedElastic(),
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(TestingCommons.tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()), null, Schedulers.immediate())
         when:
         ms.processUpstreamsEvents(
                 new UpstreamChangeEvent(Chain.ETHEREUM__MAINNET, up1, UpstreamChangeEvent.ChangeType.ADDED)
@@ -298,7 +298,7 @@ class MultistreamSpec extends Specification {
                 Schedulers.boundedElastic(),
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(TestingCommons.tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()), null, Schedulers.immediate())
         def head1 = createBlock(250, "0x0d050c785de17179f935b9b93aca09c442964cc59972c71ae68e74731448401b")
         def head2 = createBlock(270, "0x0d050c785de17179f935b9b93aca09c442964cc59972c71ae68e74731448402b")
         def head3 = createBlock(100, "0x0d050c785de17179f935b9b93aca09c442964cc59972c71ae68e74731448412b")
@@ -333,7 +333,7 @@ class MultistreamSpec extends Specification {
                 Schedulers.boundedElastic(),
                 EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(TestingCommons.tracerMock()),
                 EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                EthereumChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()), null, Schedulers.immediate())
         multistream.processUpstreamsEvents(
                 new UpstreamChangeEvent(Chain.ETHEREUM__MAINNET, up1, UpstreamChangeEvent.ChangeType.ADDED)
         )
@@ -371,7 +371,7 @@ class MultistreamSpec extends Specification {
                     Schedulers.boundedElastic(),
                     EthereumChainSpecific.INSTANCE.makeCachingReaderBuilder(TestingCommons.tracerMock()),
                     EthereumChainSpecific.INSTANCE.&localReaderBuilder,
-                    StarknetChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()))
+                    StarknetChainSpecific.INSTANCE.subscriptionBuilder(Schedulers.boundedElastic()), null, Schedulers.immediate())
         }
 
         @NotNull
diff --git a/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethodsSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethodsSpec.groovy
index f952c5d3..ddf3b128 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethodsSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/DefaultEthereumMethodsSpec.groovy
@@ -7,7 +7,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "eth_chainId is available"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         when:
         def act = methods.isAvailable("eth_chainId")
         then:
@@ -16,7 +16,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "eth_chainId is hardcoded"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         when:
         def act = methods.isHardcoded("eth_chainId")
         then:
@@ -25,7 +25,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "eth_chainId is not callable"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         when:
         def act = methods.isCallable("eth_chainId")
         then:
@@ -34,7 +34,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "Provides hardcoded correct chainId"() {
         expect:
-        new String(new DefaultEthereumMethods(chain).executeHardcoded("eth_chainId")) == id
+        new String(new DefaultEthereumMethods(chain, false).executeHardcoded("eth_chainId")) == id
         where:
         chain                  | id
         Chain.ETHEREUM__MAINNET | '"0x1"'
@@ -44,7 +44,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "Optimism chain unsupported methods"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.OPTIMISM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.OPTIMISM__MAINNET, false)
         when:
         def acc = methods.isAvailable("eth_getAccounts")
         def trans = methods.isAvailable("eth_sendTransaction")
@@ -55,7 +55,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "Has supported specific methods"() {
         expect:
-        new DefaultEthereumMethods(chain).getSupportedMethods().containsAll(methods)
+        new DefaultEthereumMethods(chain, false).getSupportedMethods().containsAll(methods)
         where:
         chain          | methods
         Chain.POLYGON__MAINNET | ["bor_getAuthor",
@@ -69,7 +69,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "Has no filter methods by default"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         when:
         def act = methods.getSupportedMethods().findAll { it.containsIgnoreCase("filter") }
         then:
@@ -78,7 +78,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "Has no trace methods by default"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         when:
         def act = methods.getSupportedMethods().findAll { it.containsIgnoreCase("trace") }
         then:
@@ -87,7 +87,7 @@ class DefaultEthereumMethodsSpec extends Specification {
 
     def "Default eth methods are available"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         expect:
         methods.isAvailable(method)
         where:
diff --git a/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/ManagedCallMethodsSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/ManagedCallMethodsSpec.groovy
index fa4c1de4..a5350d19 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/ManagedCallMethodsSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/upstream/calls/ManagedCallMethodsSpec.groovy
@@ -94,7 +94,7 @@ class ManagedCallMethodsSpec extends Specification {
     def "Use custom quorum if provided"() {
         setup:
         def managed = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 ["eth_test", "eth_foo", "eth_bar"] as Set,
                 [] as Set,
                 [] as Set,
@@ -120,7 +120,7 @@ class ManagedCallMethodsSpec extends Specification {
 
     def "Doesn't reuse same instance"() {
         def managed = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 ["eth_test"] as Set,
                 [] as Set,
                 [] as Set,
@@ -145,7 +145,7 @@ class ManagedCallMethodsSpec extends Specification {
     def "Test enable method group"() {
         setup:
         def managed = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 [] as Set,
                 [] as Set,
                 ["filter"] as Set,
@@ -169,7 +169,7 @@ class ManagedCallMethodsSpec extends Specification {
     def "Test enable method group minus one"() {
         setup:
         def managed = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 [] as Set,
                 ["eth_newPendingTransactionFilter"] as Set,
                 ["filter"] as Set,
@@ -193,7 +193,7 @@ class ManagedCallMethodsSpec extends Specification {
     def "Test disabled group not disable enabled method"() {
         setup:
         def managed = new ManagedCallMethods(
-                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET),
+                new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false),
                 ["eth_newPendingTransactionFilter"] as Set,
                 [] as Set,
                 [] as Set,
diff --git a/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumCachingReaderSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumCachingReaderSpec.groovy
index ff4d1704..43d541ce 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumCachingReaderSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumCachingReaderSpec.groovy
@@ -43,7 +43,7 @@ class EthereumDirectReaderSpec extends Specification {
             transactions = []
         }
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 Stub(Multistream), Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -70,7 +70,7 @@ class EthereumDirectReaderSpec extends Specification {
     def "Produce empty result on non-existing block"() {
         setup:
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 Stub(Multistream), Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -103,7 +103,7 @@ class EthereumDirectReaderSpec extends Specification {
             transactions = []
         }
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 Stub(Multistream), Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -136,7 +136,7 @@ class EthereumDirectReaderSpec extends Specification {
             blockHash = BlockHash.from(hash1)
         }
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 Stub(Multistream), Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -169,7 +169,7 @@ class EthereumDirectReaderSpec extends Specification {
             blockHash = BlockHash.from(hash1)
         }
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 Stub(Multistream), Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -199,7 +199,7 @@ class EthereumDirectReaderSpec extends Specification {
             blockHash = BlockHash.from(hash1)
         }
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         def caches = Mock(Caches) {
             // note that the Caches needs a Height value, otherwise it's not cached
@@ -228,7 +228,7 @@ class EthereumDirectReaderSpec extends Specification {
     def "Produce empty on non-existing tx"() {
         setup:
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 Stub(Multistream), Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -258,7 +258,7 @@ class EthereumDirectReaderSpec extends Specification {
             }
         }
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 up, Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -289,7 +289,7 @@ class EthereumDirectReaderSpec extends Specification {
             }
         }
         def calls = Mock(Factory) {
-            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            1 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 up, Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
@@ -323,7 +323,7 @@ class EthereumDirectReaderSpec extends Specification {
             transactions = []
         }
         def calls = Mock(Factory) {
-            3 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            3 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         def result = Mono.just(
                 new RpcReader.Result(
@@ -363,7 +363,7 @@ class EthereumDirectReaderSpec extends Specification {
             transactions = []
         }
         def calls = Mock(Factory) {
-            3 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            3 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         def result = Mono.just(
                 new RpcReader.Result(
@@ -400,7 +400,7 @@ class EthereumDirectReaderSpec extends Specification {
             }
         }
         def calls = Mock(Factory) {
-            4 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+            4 * create() >> new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         }
         EthereumDirectReader reader = new EthereumDirectReader(
                 up, Caches.default(), new CurrentBlockCache(), calls, TestingCommons.tracerMock()
diff --git a/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReaderSpec.groovy b/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReaderSpec.groovy
index 0807ce58..f4fd4602 100644
--- a/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReaderSpec.groovy
+++ b/src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumLocalReaderSpec.groovy
@@ -21,16 +21,17 @@ class EthereumLocalReaderSpec extends Specification {
 
     def "Calls hardcoded"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         def router = new EthereumLocalReader(
                 new EthereumCachingReader(
                         TestingCommons.multistream(TestingCommons.api()),
                         Caches.default(),
-                        ConstantFactory.constantFactory(new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)),
+                        ConstantFactory.constantFactory(new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)),
                         TestingCommons.tracerMock()
                 ),
                 methods,
-                new EmptyHead()
+                new EmptyHead(),
+                null
         )
         when:
         def act = router.read(new JsonRpcRequest("eth_coinbase", [])).block(Duration.ofSeconds(1))
@@ -40,16 +41,17 @@ class EthereumLocalReaderSpec extends Specification {
 
     def "Returns empty if nonce set"() {
         setup:
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
         def router = new EthereumLocalReader(
                 new EthereumCachingReader(
                         TestingCommons.multistream(TestingCommons.api()),
                         Caches.default(),
-                        ConstantFactory.constantFactory(new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)),
+                        ConstantFactory.constantFactory(new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)),
                         TestingCommons.tracerMock()
                 ),
                 methods,
-                new EmptyHead()
+                new EmptyHead(),
+                null
         )
         when:
         def act = router.read(new JsonRpcRequest("eth_getTransactionByHash", ["test"], 10))
@@ -72,8 +74,8 @@ class EthereumLocalReaderSpec extends Specification {
                 )
             }
         }
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
-        def router = new EthereumLocalReader(reader, methods, head)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
+        def router = new EthereumLocalReader(reader, methods, head, null)
 
         when:
         def act = router.getBlockByNumber(["latest", false])
@@ -100,8 +102,8 @@ class EthereumLocalReaderSpec extends Specification {
                 )
             }
         }
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
-        def router = new EthereumLocalReader(reader, methods, head)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
+        def router = new EthereumLocalReader(reader, methods, head, null)
 
         when:
         def act = router.getBlockByNumber(["earliest", false])
@@ -128,8 +130,8 @@ class EthereumLocalReaderSpec extends Specification {
                 )
             }
         }
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
-        def router = new EthereumLocalReader(reader, methods, head)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
+        def router = new EthereumLocalReader(reader, methods, head, null)
 
         when:
         def act = router.getBlockByNumber(["0x123ef", false])
@@ -152,8 +154,8 @@ class EthereumLocalReaderSpec extends Specification {
             _ * txByHashAsCont() >> new EmptyReader<>()
             _ * blocksByHeightAsCont() >> new EmptyReader<>()
         }
-        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET)
-        def router = new EthereumLocalReader(reader, methods, head)
+        def methods = new DefaultEthereumMethods(Chain.ETHEREUM__MAINNET, false)
+        def router = new EthereumLocalReader(reader, methods, head, null)
 
         when:
         def act = router.getBlockByNumber(["0x0", true])
diff --git a/src/test/kotlin/io/emeraldpay/dshackle/config/reload/ReloadConfigTest.kt b/src/test/kotlin/io/emeraldpay/dshackle/config/reload/ReloadConfigTest.kt
index 4750c1ab..13af79d6 100644
--- a/src/test/kotlin/io/emeraldpay/dshackle/config/reload/ReloadConfigTest.kt
+++ b/src/test/kotlin/io/emeraldpay/dshackle/config/reload/ReloadConfigTest.kt
@@ -179,6 +179,8 @@ class ReloadConfigTest {
             cs.makeCachingReaderBuilder(mock<Tracer>()),
             cs::localReaderBuilder,
             cs.subscriptionBuilder(Schedulers.boundedElastic()),
+            null,
+            Schedulers.fromExecutor(Executors.newFixedThreadPool(6)),
         )
     }