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diff --git a/opendc-harness/src/main/kotlin/org/opendc/harness/internal/CompositeDiscovery.kt b/opendc-harness/src/main/kotlin/org/opendc/harness/internal/CompositeDiscovery.kt
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+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package org.opendc.harness.internal
+
+import kotlinx.coroutines.FlowPreview
+import kotlinx.coroutines.flow.*
+import org.opendc.harness.api.ExperimentDefinition
+import org.opendc.harness.engine.discovery.Discovery
+import org.opendc.harness.engine.discovery.DiscoveryProvider
+import org.opendc.harness.engine.discovery.DiscoveryRequest
+
+/**
+ * A composite [Discovery] instance that combines the results of multiple delegate instances.
+ */
+internal class CompositeDiscovery(providers: Iterable<DiscoveryProvider>) : Discovery {
+    /**
+     * The [Discovery] instances to delegate to.
+     */
+    private val delegates = providers.map { it.create() }
+
+    @OptIn(FlowPreview::class)
+    override fun discover(request: DiscoveryRequest): Flow<ExperimentDefinition> {
+        return delegates.asFlow()
+            .map { it.discover(request) }
+            .flattenMerge(delegates.size)
+    }
+}