diff --git a/.buildconfig-android.yml b/.buildconfig-android.yml
index 8bf1d39d1..a6e0565f3 100644
--- a/.buildconfig-android.yml
+++ b/.buildconfig-android.yml
@@ -57,6 +57,13 @@ projects:
       - name: sync15
         type: aar
     description: Shared Sync types for Kotlin.
+  syncmanager:
+    path: components/sync_manager/android
+    artifactId: syncmanager
+    publications:
+      - name: syncmanager
+        type: aar
+    description: Sync manager implementation
   lockbox-megazord:
     uploadSymbols: true
     path: megazords/lockbox/android
diff --git a/Cargo.lock b/Cargo.lock
index 3d5a78bf7..a8c207f18 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -623,6 +623,7 @@ dependencies = [
  "places-ffi 0.1.0",
  "push-ffi 0.1.0",
  "rc_log_ffi 0.1.0",
+ "sync_manager_ffi 0.1.0",
  "viaduct 0.1.0",
 ]
 
@@ -1028,6 +1029,7 @@ dependencies = [
  "fxaclient_ffi 0.1.0",
  "logins_ffi 0.1.0",
  "rc_log_ffi 0.1.0",
+ "sync_manager_ffi 0.1.0",
  "viaduct 0.1.0",
 ]
 
@@ -1107,6 +1109,7 @@ dependencies = [
  "places-ffi 0.1.0",
  "push-ffi 0.1.0",
  "rc_log_ffi 0.1.0",
+ "sync_manager_ffi 0.1.0",
  "viaduct 0.1.0",
 ]
 
@@ -2351,6 +2354,37 @@ dependencies = [
  "viaduct 0.1.0",
 ]
 
+[[package]]
+name = "sync_manager"
+version = "0.1.0"
+dependencies = [
+ "bytes 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "error-support 0.1.0",
+ "failure 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ffi-support 0.3.5",
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "logins 0.1.0",
+ "places 0.1.0",
+ "prost 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "prost-build 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "prost-derive 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sync15 0.1.0",
+]
+
+[[package]]
+name = "sync_manager_ffi"
+version = "0.1.0"
+dependencies = [
+ "ffi-support 0.3.5",
+ "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "logins_ffi 0.1.0",
+ "places-ffi 0.1.0",
+ "prost 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sync15 0.1.0",
+ "sync_manager 0.1.0",
+]
+
 [[package]]
 name = "synstructure"
 version = "0.10.2"
diff --git a/Cargo.toml b/Cargo.toml
index 6650a880a..ea4895c98 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,6 +20,8 @@ members = [
     "components/support/rc_crypto/nss/nss_sys",
     "components/viaduct",
     "components/sync15",
+    "components/sync_manager",
+    "components/sync_manager/ffi",
     "components/rc_log",
     "megazords/fenix",
     "megazords/full",
diff --git a/components/logins/android/src/main/java/mozilla/appservices/logins/DatabaseLoginsStorage.kt b/components/logins/android/src/main/java/mozilla/appservices/logins/DatabaseLoginsStorage.kt
index 90d0d8a5a..25683b653 100644
--- a/components/logins/android/src/main/java/mozilla/appservices/logins/DatabaseLoginsStorage.kt
+++ b/components/logins/android/src/main/java/mozilla/appservices/logins/DatabaseLoginsStorage.kt
@@ -29,6 +29,17 @@ class DatabaseLoginsStorage(private val dbPath: String) : AutoCloseable, LoginsS
         return handle
     }
 
+    /**
+     * Return the raw handle used to reference this logins database.
+     *
+     * Generally should only be used to pass the handle into `SyncManager.setLogins`.
+     *
+     * Note: handles do not remain valid after locking / unlocking the logins database.
+     */
+    fun getHandle(): Long {
+        return this.raw.get()
+    }
+
     @Synchronized
     @Throws(LoginsStorageException::class)
     override fun lock() {
diff --git a/components/logins/ffi/src/lib.rs b/components/logins/ffi/src/lib.rs
index 6c3e7b3ca..1e61ad141 100644
--- a/components/logins/ffi/src/lib.rs
+++ b/components/logins/ffi/src/lib.rs
@@ -14,9 +14,13 @@ use ffi_support::{
 };
 use logins::{Login, PasswordEngine, Result};
 use std::os::raw::c_char;
+use std::sync::{Arc, Mutex};
 
 lazy_static::lazy_static! {
-    static ref ENGINES: ConcurrentHandleMap<PasswordEngine> = ConcurrentHandleMap::new();
+    // TODO: this is basically a RwLock<HandleMap<Mutex<Arc<Mutex<...>>>>.
+    // but could just be a `RwLock<HandleMap<Arc<Mutex<...>>>>`.
+    // Find a way to express this cleanly in ffi_support?
+    pub static ref ENGINES: ConcurrentHandleMap<Arc<Mutex<PasswordEngine>>> = ConcurrentHandleMap::new();
 }
 
 #[no_mangle]
@@ -26,10 +30,10 @@ pub extern "C" fn sync15_passwords_state_new(
     error: &mut ExternError,
 ) -> u64 {
     log::debug!("sync15_passwords_state_new");
-    ENGINES.insert_with_result(error, || {
+    ENGINES.insert_with_result(error, || -> logins::Result<_> {
         let path = db_path.as_str();
         let key = encryption_key.as_str();
-        PasswordEngine::new(path, Some(key))
+        Ok(Arc::new(Mutex::new(PasswordEngine::new(path, Some(key))?)))
     })
 }
 
@@ -65,12 +69,15 @@ pub unsafe extern "C" fn sync15_passwords_state_new_with_hex_key(
     error: &mut ExternError,
 ) -> u64 {
     log::debug!("sync15_passwords_state_new_with_hex_key");
-    ENGINES.insert_with_result(error, || {
+    ENGINES.insert_with_result(error, || -> logins::Result<_> {
         let path = db_path.as_str();
         let key = bytes_to_key_string(encryption_key, encryption_key_len as usize);
         // We have a Option<String>, but need an Option<&str>...
         let opt_key_ref = key.as_ref().map(String::as_str);
-        PasswordEngine::new(path, opt_key_ref)
+        Ok(Arc::new(Mutex::new(PasswordEngine::new(
+            path,
+            opt_key_ref,
+        )?)))
     })
 }
 
@@ -83,7 +90,7 @@ fn parse_url(url: &str) -> sync15::Result<url::Url> {
 pub extern "C" fn sync15_passwords_disable_mem_security(handle: u64, error: &mut ExternError) {
     log::debug!("sync15_passwords_disable_mem_security");
     ENGINES.call_with_result(error, handle, |state| -> Result<()> {
-        state.disable_mem_security()
+        state.lock().unwrap().disable_mem_security()
     })
 }
 
@@ -98,7 +105,7 @@ pub extern "C" fn sync15_passwords_sync(
 ) -> *mut c_char {
     log::debug!("sync15_passwords_sync");
     ENGINES.call_with_result(error, handle, |state| -> Result<_> {
-        let ping = state.sync(
+        let ping = state.lock().unwrap().sync(
             &sync15::Sync15StorageClientInit {
                 key_id: key_id.into_string(),
                 access_token: access_token.into_string(),
@@ -113,7 +120,9 @@ pub extern "C" fn sync15_passwords_sync(
 #[no_mangle]
 pub extern "C" fn sync15_passwords_touch(handle: u64, id: FfiStr<'_>, error: &mut ExternError) {
     log::debug!("sync15_passwords_touch");
-    ENGINES.call_with_result(error, handle, |state| state.touch(id.as_str()))
+    ENGINES.call_with_result(error, handle, |state| {
+        state.lock().unwrap().touch(id.as_str())
+    })
 }
 
 #[no_mangle]
@@ -123,25 +132,27 @@ pub extern "C" fn sync15_passwords_delete(
     error: &mut ExternError,
 ) -> u8 {
     log::debug!("sync15_passwords_delete");
-    ENGINES.call_with_result(error, handle, |state| state.delete(id.as_str()))
+    ENGINES.call_with_result(error, handle, |state| {
+        state.lock().unwrap().delete(id.as_str())
+    })
 }
 
 #[no_mangle]
 pub extern "C" fn sync15_passwords_wipe(handle: u64, error: &mut ExternError) {
     log::debug!("sync15_passwords_wipe");
-    ENGINES.call_with_result(error, handle, |state| state.wipe())
+    ENGINES.call_with_result(error, handle, |state| state.lock().unwrap().wipe())
 }
 
 #[no_mangle]
 pub extern "C" fn sync15_passwords_wipe_local(handle: u64, error: &mut ExternError) {
     log::debug!("sync15_passwords_wipe_local");
-    ENGINES.call_with_result(error, handle, |state| state.wipe_local())
+    ENGINES.call_with_result(error, handle, |state| state.lock().unwrap().wipe_local())
 }
 
 #[no_mangle]
 pub extern "C" fn sync15_passwords_reset(handle: u64, error: &mut ExternError) {
     log::debug!("sync15_passwords_reset");
-    ENGINES.call_with_result(error, handle, |state| state.reset())
+    ENGINES.call_with_result(error, handle, |state| state.lock().unwrap().reset())
 }
 
 #[no_mangle]
@@ -150,7 +161,9 @@ pub extern "C" fn sync15_passwords_new_interrupt_handle(
     error: &mut ExternError,
 ) -> *mut sql_support::SqlInterruptHandle {
     log::debug!("sync15_passwords_new_interrupt_handle");
-    ENGINES.call_with_output(error, handle, |state| state.new_interrupt_handle())
+    ENGINES.call_with_output(error, handle, |state| {
+        state.lock().unwrap().new_interrupt_handle()
+    })
 }
 
 #[no_mangle]
@@ -166,7 +179,7 @@ pub extern "C" fn sync15_passwords_interrupt(
 pub extern "C" fn sync15_passwords_get_all(handle: u64, error: &mut ExternError) -> *mut c_char {
     log::debug!("sync15_passwords_get_all");
     ENGINES.call_with_result(error, handle, |state| -> Result<String> {
-        let all_passwords = state.list()?;
+        let all_passwords = state.lock().unwrap().list()?;
         let result = serde_json::to_string(&all_passwords)?;
         Ok(result)
     })
@@ -179,7 +192,9 @@ pub extern "C" fn sync15_passwords_get_by_id(
     error: &mut ExternError,
 ) -> *mut c_char {
     log::debug!("sync15_passwords_get_by_id");
-    ENGINES.call_with_result(error, handle, |state| state.get(id.as_str()))
+    ENGINES.call_with_result(error, handle, |state| {
+        state.lock().unwrap().get(id.as_str())
+    })
 }
 
 #[no_mangle]
@@ -196,7 +211,7 @@ pub extern "C" fn sync15_passwords_add(
             parsed["id"] = serde_json::Value::String(String::default());
         }
         let login: Login = serde_json::from_value(parsed)?;
-        state.add(login)
+        state.lock().unwrap().add(login)
     })
 }
 
@@ -222,7 +237,7 @@ pub extern "C" fn sync15_passwords_update(
     log::debug!("sync15_passwords_update");
     ENGINES.call_with_result(error, handle, |state| {
         let parsed: Login = serde_json::from_str(record_json.as_str())?;
-        state.update(parsed)
+        state.lock().unwrap().update(parsed)
     });
 }
 
diff --git a/components/places/android/src/main/java/mozilla/appservices/places/PlacesConnection.kt b/components/places/android/src/main/java/mozilla/appservices/places/PlacesConnection.kt
index 84160c8da..713018caa 100644
--- a/components/places/android/src/main/java/mozilla/appservices/places/PlacesConnection.kt
+++ b/components/places/android/src/main/java/mozilla/appservices/places/PlacesConnection.kt
@@ -45,6 +45,15 @@ class PlacesApi(path: String) : PlacesManager, AutoCloseable {
         private const val READ_WRITE: Int = 2
     }
 
+    /**
+     * Return the raw handle used to reference this PlacesApi.
+     *
+     * Generally should only be used to pass the handle into `SyncManager.setPlaces`
+     */
+    fun getHandle(): Long {
+        return this.handle.get()
+    }
+
     override fun openReader(): PlacesReaderConnection {
         val connHandle = rustCall(this) { error ->
             LibPlacesFFI.INSTANCE.places_connection_new(handle.get(), READ_ONLY, error)
diff --git a/components/places/ffi/src/lib.rs b/components/places/ffi/src/lib.rs
index 9f1ac1433..9a018a3d4 100644
--- a/components/places/ffi/src/lib.rs
+++ b/components/places/ffi/src/lib.rs
@@ -30,7 +30,7 @@ fn parse_url(url: &str) -> places::Result<url::Url> {
 }
 
 lazy_static::lazy_static! {
-    static ref APIS: ConcurrentHandleMap<Arc<PlacesApi>> = ConcurrentHandleMap::new();
+    pub static ref APIS: ConcurrentHandleMap<Arc<PlacesApi>> = ConcurrentHandleMap::new();
     static ref CONNECTIONS: ConcurrentHandleMap<PlacesDb> = ConcurrentHandleMap::new();
 }
 
diff --git a/components/sync_manager/Cargo.toml b/components/sync_manager/Cargo.toml
new file mode 100644
index 000000000..49cbcfbd8
--- /dev/null
+++ b/components/sync_manager/Cargo.toml
@@ -0,0 +1,22 @@
+[package]
+name = "sync_manager"
+version = "0.1.0"
+authors = ["application-services <application-services@mozilla.com>"]
+edition = "2018"
+license = "MPL-2.0"
+
+[dependencies]
+sync15 = { path = "../sync15" }
+places = { path = "../places", optional = true }
+logins = { path = "../logins", optional = true }
+ffi-support = { path = "../support/ffi" }
+failure = "0.1.5"
+error-support = { path = "../support/error" }
+prost = "0.5.0"
+prost-derive = "0.5.0"
+bytes = "0.4.12"
+lazy_static = "1.3.0"
+log = "0.4.7"
+
+[build-dependencies]
+prost-build = "0.5.0"
diff --git a/components/sync_manager/android/build.gradle b/components/sync_manager/android/build.gradle
new file mode 100644
index 000000000..0cc68b1fa
--- /dev/null
+++ b/components/sync_manager/android/build.gradle
@@ -0,0 +1,120 @@
+apply plugin: 'com.android.library'
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'
+apply plugin: 'com.google.protobuf'
+
+android {
+    compileSdkVersion rootProject.ext.build.compileSdkVersion
+
+    defaultConfig {
+        minSdkVersion rootProject.ext.build['minSdkVersion']
+        targetSdkVersion rootProject.ext.build['targetSdkVersion']
+
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        buildConfigField("String", "LIBRARY_VERSION", "\"${rootProject.ext.library.version}\"")
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+            consumerProguardFiles "$rootDir/proguard-rules-consumer-jna.pro"
+        }
+    }
+
+    sourceSets {
+        test.resources.srcDirs += "$buildDir/rustJniLibs/desktop"
+        test.resources.srcDirs += "${project(':full-megazord').buildDir}/rustJniLibs/desktop"
+
+        main {
+            proto {
+                srcDir '../src'
+            }
+        }
+    }
+}
+
+configurations {
+    // There's an interaction between Gradle's resolution of dependencies with different types
+    // (@jar, @aar) for `implementation` and `testImplementation` and with Android Studio's built-in
+    // JUnit test runner.  The runtime classpath in the built-in JUnit test runner gets the
+    // dependency from the `implementation`, which is type @aar, and therefore the JNA dependency
+    // doesn't provide the JNI dispatch libraries in the correct Java resource directories.  I think
+    // what's happening is that @aar type in `implementation` resolves to the @jar type in
+    // `testImplementation`, and that it wins the dependency resolution battle.
+    //
+    // A workaround is to add a new configuration which depends on the @jar type and to reference
+    // the underlying JAR file directly in `testImplementation`.  This JAR file doesn't resolve to
+    // the @aar type in `implementation`.  This works when invoked via `gradle`, but also sets the
+    // correct runtime classpath when invoked with Android Studio's built-in JUnit test runner.
+    // Success!
+    jnaForTest
+}
+protobuf {
+    protoc {
+        artifact = 'com.google.protobuf:protoc:3.0.0'
+    }
+    plugins {
+        javalite {
+            artifact = 'com.google.protobuf:protoc-gen-javalite:3.0.0'
+        }
+    }
+    generateProtoTasks {
+        all().each { task ->
+            task.builtins {
+                remove java
+            }
+            task.plugins {
+                javalite { }
+            }
+        }
+    }
+}
+
+dependencies {
+    // Part of the public API.
+    api project(':sync15')
+
+    jnaForTest "net.java.dev.jna:jna:$jna_version@jar"
+    implementation "net.java.dev.jna:jna:$jna_version@aar"
+
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+
+    implementation 'com.google.protobuf:protobuf-lite:3.0.0'
+    api project(":full-megazord")
+    implementation project(":native-support")
+
+    // For reasons unknown, resolving the jnaForTest configuration directly
+    // trips a nasty issue with the Android-Gradle plugin 3.2.1, like `Cannot
+    // change attributes of configuration ':PROJECT:kapt' after it has been
+    // resolved`.  I think that the configuration is being made a
+    // super-configuration of the testImplementation and then the `.files` is
+    // causing it to be resolved.  Cloning first dissociates the configuration,
+    // avoiding other configurations from being resolved.  Tricky!
+    testImplementation files(configurations.jnaForTest.copyRecursive().files)
+    testImplementation 'junit:junit:4.12'
+    testImplementation 'org.robolectric:robolectric:3.8'
+    testImplementation 'org.mockito:mockito-core:2.21.0'
+
+    androidTestImplementation 'com.android.support.test:runner:1.0.2'
+    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
+}
+
+afterEvaluate {
+    // The `cargoBuild` task isn't available until after evaluation.
+    android.libraryVariants.all { variant ->
+        def productFlavor = ""
+        variant.productFlavors.each {
+            productFlavor += "${it.name.capitalize()}"
+        }
+        def buildType = "${variant.buildType.name.capitalize()}"
+        tasks["generate${productFlavor}${buildType}Assets"].dependsOn(project(':full-megazord').tasks["cargoBuild"])
+
+        // For unit tests.
+        tasks["process${productFlavor}${buildType}UnitTestJavaRes"].dependsOn(project(':full-megazord').tasks["cargoBuild"])
+    }
+}
+
+apply from: "$rootDir/publish.gradle"
+
+ext.configurePublish()
diff --git a/components/sync_manager/android/proguard-rules.pro b/components/sync_manager/android/proguard-rules.pro
new file mode 100644
index 000000000..f1b424510
--- /dev/null
+++ b/components/sync_manager/android/proguard-rules.pro
@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile
diff --git a/components/sync_manager/android/src/main/AndroidManifest.xml b/components/sync_manager/android/src/main/AndroidManifest.xml
new file mode 100644
index 000000000..1092153a7
--- /dev/null
+++ b/components/sync_manager/android/src/main/AndroidManifest.xml
@@ -0,0 +1,2 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="org.mozilla.appservices.syncmanager" />
diff --git a/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/Errors.kt b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/Errors.kt
new file mode 100644
index 000000000..c2763af81
--- /dev/null
+++ b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/Errors.kt
@@ -0,0 +1,41 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package mozilla.appservices.syncmanager
+
+/**
+ * Base class for sync manager errors. Generally should not
+ * have concrete instances.
+ */
+open class SyncManagerException(msg: String) : Exception(msg)
+
+/**
+ * General catch-all error, generally indicating API misuse of some sort.
+ */
+open class UnexpectedError(msg: String) : SyncManagerException(msg)
+
+/**
+ * The sync manager paniced. Please report these.
+ */
+open class InternalPanic(msg: String) : SyncManagerException(msg)
+
+/**
+ * We were asked to sync an engine which is either unknown, or which the sync
+ * manager was not compiled with support for (message will elaborate).
+ */
+open class UnsupportedEngine(msg: String) : SyncManagerException(msg)
+
+/**
+ * We were asked to sync an engine but we couldn't because the connection
+ *
+ * Note: When not syncing, the manager holds a weak reference to connection
+ * objects, and so performing something like: `SyncManager.setLogins(handle)`,
+ * closing/locking the logins connection, and then trying to sync logins will
+ * produce this error.
+ *
+ * TODO: Should this be an error reported in SyncResult and not cause the sync
+ * to fail? It's probably a bug in the caller (they should call `setBlah` first)...
+ */
+open class ClosedEngine(msg: String) : SyncManagerException(msg)
+
diff --git a/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/LibSyncManagerFFI.kt b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/LibSyncManagerFFI.kt
new file mode 100644
index 000000000..0a7cec834
--- /dev/null
+++ b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/LibSyncManagerFFI.kt
@@ -0,0 +1,32 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package mozilla.appservices.syncmanager
+
+import com.sun.jna.Library
+import com.sun.jna.Pointer
+import com.sun.jna.PointerType
+import com.sun.jna.StringArray
+import mozilla.appservices.support.native.RustBuffer
+import mozilla.appservices.support.native.loadIndirect
+import org.mozilla.appservices.syncmanager.BuildConfig
+
+@Suppress("FunctionNaming", "FunctionParameterNaming", "LongParameterList", "TooGenericExceptionThrown")
+internal interface LibSyncManagerFFI : Library {
+    companion object {
+        internal var INSTANCE: LibSyncManagerFFI =
+            loadIndirect(componentName = "syncmanager", componentVersion = BuildConfig.LIBRARY_VERSION)
+    }
+    fun sync_manager_set_places(handle: PlacesApiHandle, error: RustError.ByReference)
+    fun sync_manager_set_logins(handle: LoginsDbHandle, error: RustError.ByReference)
+    fun sync_manager_disconnect(error: RustError.ByReference)
+
+    fun sync_manager_sync(data: Pointer, len: Int, error: RustError.ByReference): RustBuffer.ByValue
+
+    fun sync_manager_destroy_string(s: Pointer)
+    fun sync_manager_destroy_bytebuffer(bb: RustBuffer.ByValue)
+}
+
+internal typealias PlacesApiHandle = Long
+internal typealias LoginsDbHandle = Long
diff --git a/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/RustError.kt b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/RustError.kt
new file mode 100644
index 000000000..b039a7130
--- /dev/null
+++ b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/RustError.kt
@@ -0,0 +1,69 @@
+/* Copyright 2018 Mozilla
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+package mozilla.appservices.syncmanager
+
+import com.sun.jna.Pointer
+import com.sun.jna.Structure
+
+@Structure.FieldOrder("code", "message")
+internal open class RustError : Structure() {
+
+    class ByReference : RustError(), Structure.ByReference
+
+    @JvmField var code: Int = 0
+    @JvmField var message: Pointer? = null
+
+    fun isSuccess(): Boolean {
+        return code == 0
+    }
+
+    fun isFailure(): Boolean {
+        return code != 0
+    }
+
+    @Suppress("ComplexMethod", "ReturnCount", "TooGenericExceptionThrown")
+    fun intoException(): SyncManagerException {
+        if (!isFailure()) {
+            // It's probably a bad idea to throw here! We're probably leaking something if this is
+            // ever hit! (But we shouldn't ever hit it?)
+            throw RuntimeException("[Bug] intoException called on non-failure!")
+        }
+        val message = this.consumeErrorMessage()
+        when (code) {
+            2 -> return UnsupportedEngine(message)
+            3 -> return ClosedEngine(message)
+            -1 -> return InternalPanic(message)
+            // Note: `1` is used as a generic catch all, but we
+            // might as well handle the others the same way.
+            else -> return UnexpectedError(message)
+        }
+    }
+
+    /**
+     * Get and consume the error message, or null if there is none.
+     */
+    fun consumeErrorMessage(): String {
+        val result = this.getMessage()
+        if (this.message != null) {
+            LibSyncManagerFFI.INSTANCE.sync_manager_destroy_string(this.message!!)
+            this.message = null
+        }
+        if (result == null) {
+            throw NullPointerException("consumeErrorMessage called with null message!")
+        }
+        return result
+    }
+
+    /**
+     * Get the error message or null if there is none.
+     */
+    fun getMessage(): String? {
+        return this.message?.getString(0, "utf8")
+    }
+}
diff --git a/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncManager.kt b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncManager.kt
new file mode 100644
index 000000000..8f07d1d1f
--- /dev/null
+++ b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncManager.kt
@@ -0,0 +1,72 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package mozilla.appservices.syncmanager
+
+import com.sun.jna.Native
+import mozilla.appservices.support.native.toNioDirectBuffer
+
+object SyncManager {
+
+    /**
+     * Point the manager at the implementation of `PlacesApi` to use.
+     *
+     * @param placesApiHandle A value returned by `PlacesApi.getHandle()`
+     * @throws [UnsupportedEngine] If the manager was not compiled with places support.
+     */
+    fun setPlaces(placesApiHandle: Long) {
+        rustCall { err ->
+            LibSyncManagerFFI.INSTANCE.sync_manager_set_places(placesApiHandle, err)
+        }
+    }
+    /**
+     * Point the manager at the implementation of `DatabaseLoginsStorage` to use.
+     *
+     * @param loginsDbHandle A value returned by `DatabaseLoginsStorage.getHandle()`
+     * @throws [UnsupportedEngine] If the manager was not compiled with logins support.
+     */
+    fun setLogins(loginsDbHandle: Long) {
+        rustCall { err ->
+            LibSyncManagerFFI.INSTANCE.sync_manager_set_logins(loginsDbHandle, err)
+        }
+    }
+
+    /**
+     * Disconnect this device from sync. This essentially clears shared state having to do with
+     * sync, as well as each engines sync-specific local state
+     */
+    fun disconnect() {
+        rustCall { err ->
+            LibSyncManagerFFI.INSTANCE.sync_manager_disconnect(err)
+        }
+    }
+    /**
+     * Perform a sync.
+     */
+    fun sync(params: SyncParams): SyncResult {
+        val buf = params.toProtobuf()
+        val (nioBuf, len) = buf.toNioDirectBuffer()
+        val rustBuf = rustCall { err ->
+            val ptr = Native.getDirectBufferPointer(nioBuf)
+            LibSyncManagerFFI.INSTANCE.sync_manager_sync(ptr, len, err)
+        }
+
+        try {
+            val stream = rustBuf.asCodedInputStream()
+            return SyncResult.fromProtobuf(MsgTypes.SyncResult.parseFrom(stream))
+        } finally {
+            LibSyncManagerFFI.INSTANCE.sync_manager_destroy_bytebuffer(rustBuf)
+        }
+    }
+}
+
+internal inline fun <U> rustCall(callback: (RustError.ByReference) -> U): U {
+    val e = RustError.ByReference()
+    val ret: U = callback(e)
+    if (e.isFailure()) {
+        throw e.intoException()
+    } else {
+        return ret
+    }
+}
diff --git a/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncParams.kt b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncParams.kt
new file mode 100644
index 000000000..d905b6a4a
--- /dev/null
+++ b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncParams.kt
@@ -0,0 +1,119 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package mozilla.appservices.syncmanager
+
+/**
+ * Reason for syncing.
+ */
+enum class SyncReason {
+    /**
+     * This is a scheduled sync
+     */
+    SCHEDULED,
+    /**
+     * This is a manually triggered sync invoked by the user.
+     */
+    USER,
+    /**
+     * This is a sync that is running optimistically before
+     * the device goes to sleep / is backgrounded.
+     */
+    PRE_SLEEP,
+    /**
+     * This is a sync that is run on application startup.
+     */
+    STARTUP,
+    /**
+     * This is a sync that is being performed simply to update the
+     * enabled state of one or more engines.
+     */
+    ENABLED_CHANGE,
+}
+
+/**
+ * A class for providing the auth-related information needed to sync.
+ */
+data class SyncAuthInfo(
+    val kid: String,
+    val fxaAccessToken: String,
+    val syncKey: String,
+    val tokenserverURL: String
+)
+
+/**
+ * Parameters to use for syncing.
+ */
+data class SyncParams(
+    /**
+     * The reason we're syncing.
+     */
+    val reason: SyncReason,
+    /**
+     * The list of engines to sync.
+     *
+     * Engine names are lowercase, and refer to the server-side engine name, e.g.
+     * "passwords" (not "logins"!), "bookmarks", "history", etc.
+     *
+     * Requesting that we sync an unknown engine type will result in a
+     * [UnsupportedEngine] error.
+     *
+     * Passing `null` here is used to indicate that all known engines
+     * should be synced.
+     */
+    val engines: List<String>?,
+
+    /**
+     * A map of engine name to new-enabled-state. That is,
+     *
+     * - The map should be empty to indicate "no changes"
+     *
+     * - The map should have `enginename: true` if an engine named
+     *   `enginename` should be enabled.
+     *
+     * - The map should have `enginename: false` if an engine named
+     *   `enginename` should be disabled.
+     */
+    val enabledChanges: Map<String, Boolean>,
+
+    /**
+     * The information used to authenticate with the sync server.
+     */
+    val authInfo: SyncAuthInfo,
+
+    /**
+     * The previously persisted sync state (from `SyncResult.persistedState`),
+     * if any exists.
+     */
+    val persistedState: String?
+) {
+    internal fun toProtobuf(): MsgTypes.SyncParams {
+        val builder = MsgTypes.SyncParams.newBuilder()
+
+        this.engines?.let {
+            builder.addAllEnginesToSync(it)
+            builder.syncAllEngines = false
+        } ?: run {
+            // Null `engines`, sync everything.
+            builder.syncAllEngines = true
+        }
+
+        builder.reason = when (this.reason) {
+            SyncReason.SCHEDULED -> MsgTypes.SyncReason.SCHEDULED
+            SyncReason.USER -> MsgTypes.SyncReason.USER
+            SyncReason.PRE_SLEEP -> MsgTypes.SyncReason.PRE_SLEEP
+            SyncReason.STARTUP -> MsgTypes.SyncReason.STARTUP
+            SyncReason.ENABLED_CHANGE -> MsgTypes.SyncReason.ENABLED_CHANGE
+        }
+
+        builder.putAllEnginesToChangeState(this.enabledChanges)
+
+        builder.acctAccessToken = this.authInfo.fxaAccessToken
+        builder.acctSyncKey = this.authInfo.syncKey
+        builder.acctKeyId = this.authInfo.kid
+        builder.acctTokenserverUrl = this.authInfo.tokenserverURL
+
+        return builder.build()
+    }
+}
diff --git a/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncResult.kt b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncResult.kt
new file mode 100644
index 000000000..f6791a7aa
--- /dev/null
+++ b/components/sync_manager/android/src/main/java/mozilla/appservices/syncmanager/SyncResult.kt
@@ -0,0 +1,150 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package mozilla.appservices.syncmanager
+
+import mozilla.appservices.sync15.SyncTelemetryPing
+
+/**
+ * Indicates, at a high level whether the sync succeeded or failed.
+ */
+enum class SyncServiceStatus {
+    /**
+     * The sync did not fail.
+     */
+    OK,
+
+    /**
+     * The sync failed due to network problems.
+     */
+    NETWORK_ERROR,
+
+    /**
+     * The sync failed due to some apparent error with the servers.
+     */
+    SERVICE_ERROR,
+
+    /**
+     * The auth information we were provided was somehow invalid. Refreshing it
+     * with FxA may resolve this issue.
+     */
+    AUTH_ERROR,
+
+    /**
+     * Indicates that we declined to sync because the server had requested a
+     * backoff which has not yet expired.
+     */
+    BACKED_OFF,
+
+    /**
+     * Some other error occurred.
+     */
+    OTHER_ERROR,
+}
+
+/**
+ * The result of a sync.
+ */
+data class SyncResult(
+    /**
+     * The general health.
+     */
+    val status: SyncServiceStatus,
+
+    /**
+     * For engines which failed to sync, contains a string
+     * description of the error.
+     *
+     * The error strings are mostly provided for local debugging,
+     * and more robust information is present in e.g. telemetry.
+     */
+    val failures: Map<String, String>,
+
+    /**
+     * The list of engines which synced without any errors.
+     */
+    val successful: List<String>,
+
+    /**
+     * The state string that should be persisted by the caller, and
+     * used as the value for `SyncParams.persistedState` in subsequent
+     * calls to `SyncManager.sync`.
+     */
+    val persistedState: String,
+
+    /**
+     * The list of engines which have been declined by the user.
+     *
+     * Null if we didn't make it far enough to know.
+     */
+    val declined: List<String>?,
+
+    /**
+     * The next time we're allowed to sync, in milliseconds since
+     * the unix epoch.
+     *
+     * If this value is in the future, then there's some kind of back-off.
+     * Note that it's not necessary for the app to enforce this, but should
+     * probably be used as an input in the application's sync scheduling logic.
+     *
+     * Syncs before this passes will generally fail with a BACKED_OFF error,
+     * unless they are syncs that were manually requested by the user (that
+     * is, they have the reason `SyncReason.USER`).
+     */
+    val nextSyncAllowedAt: Long?,
+
+    /**
+     * A bundle of telemetry information recorded during this sync.
+     */
+    val telemetry: SyncTelemetryPing?
+) {
+    companion object {
+        internal fun fromProtobuf(pb: MsgTypes.SyncResult): SyncResult {
+            val nextSyncAllowedAt = if (pb.hasNextSyncAllowedAt()) {
+                pb.nextSyncAllowedAt
+            } else {
+                null
+            }
+
+            val declined = if (pb.haveDeclined) {
+                pb.declinedList
+            } else {
+                null
+            }
+
+            val successful = pb.resultsMap.entries
+                .filter { it.value.isEmpty() }
+                .map { it.key }
+                .toList()
+
+            val failures = pb.resultsMap.filter { it.value.isNotEmpty() }
+
+            val telemetry = if (pb.hasTelemetryJson()) {
+                SyncTelemetryPing.fromJSONString(pb.telemetryJson)
+            } else {
+                null
+            }
+
+            val status = when (pb.status) {
+                MsgTypes.ServiceStatus.OK -> SyncServiceStatus.OK
+                MsgTypes.ServiceStatus.NETWORK_ERROR -> SyncServiceStatus.NETWORK_ERROR
+                MsgTypes.ServiceStatus.SERVICE_ERROR -> SyncServiceStatus.SERVICE_ERROR
+                MsgTypes.ServiceStatus.AUTH_ERROR -> SyncServiceStatus.AUTH_ERROR
+                MsgTypes.ServiceStatus.BACKED_OFF -> SyncServiceStatus.BACKED_OFF
+                MsgTypes.ServiceStatus.OTHER_ERROR -> SyncServiceStatus.OTHER_ERROR
+                else -> SyncServiceStatus.OTHER_ERROR // impossible *sigh*
+            }
+
+            return SyncResult(
+                status = status,
+                failures = failures,
+                successful = successful,
+                declined = declined,
+                telemetry = telemetry,
+                nextSyncAllowedAt = nextSyncAllowedAt,
+                persistedState = pb.persistedState
+            )
+        }
+    }
+}
diff --git a/components/sync_manager/build.rs b/components/sync_manager/build.rs
new file mode 100644
index 000000000..43d878d79
--- /dev/null
+++ b/components/sync_manager/build.rs
@@ -0,0 +1,8 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+fn main() {
+    println!("cargo:rerun-if-changed=src/manager_msg_types.proto");
+    prost_build::compile_protos(&["src/manager_msg_types.proto"], &["src/"]).unwrap();
+}
diff --git a/components/sync_manager/ffi/Cargo.toml b/components/sync_manager/ffi/Cargo.toml
new file mode 100644
index 000000000..8b3bf8f9b
--- /dev/null
+++ b/components/sync_manager/ffi/Cargo.toml
@@ -0,0 +1,19 @@
+[package]
+name = "sync_manager_ffi"
+version = "0.1.0"
+authors = ["application-services <application-services@mozilla.com>"]
+edition = "2018"
+license = "MPL-2.0"
+
+[features]
+logins = ["sync_manager/logins", "logins_ffi"]
+places = ["sync_manager/places", "places-ffi"]
+
+[dependencies]
+sync_manager = { path = ".." }
+sync15 = { path = "../../sync15" }
+ffi-support = { path = "../../support/ffi" }
+places-ffi = { path = "../../places/ffi", optional = true }
+logins_ffi = { path = "../../logins/ffi", optional = true  }
+prost = "0.5.0"
+log = "0.4.7"
diff --git a/components/sync_manager/ffi/src/lib.rs b/components/sync_manager/ffi/src/lib.rs
new file mode 100644
index 000000000..c38537b8d
--- /dev/null
+++ b/components/sync_manager/ffi/src/lib.rs
@@ -0,0 +1,84 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#![allow(unknown_lints)]
+#![warn(rust_2018_idioms)]
+// Let's allow these in the FFI code, since it's usually just a coincidence if
+// the closure is small.
+#![allow(clippy::redundant_closure)]
+
+use ffi_support::{ExternError, HandleError};
+use sync_manager::Result as MgrResult;
+
+#[no_mangle]
+pub extern "C" fn sync_manager_set_places(_places_api_handle: u64, error: &mut ExternError) {
+    ffi_support::call_with_result(error, || -> MgrResult<()> {
+        #[cfg(feature = "places")]
+        {
+            let api = places_ffi::APIS
+                .get_u64(_places_api_handle, |api| -> Result<_, HandleError> {
+                    Ok(std::sync::Arc::clone(api))
+                })?;
+            sync_manager::set_places(api);
+            Ok(())
+        }
+        #[cfg(not(feature = "places"))]
+        {
+            log::error!("Sync manager not compiled with places support");
+            Err(sync_manager::ErrorKind::UnsupportedFeature("places".to_string()).into())
+        }
+    })
+}
+
+#[no_mangle]
+pub extern "C" fn sync_manager_set_logins(_logins_handle: u64, error: &mut ExternError) {
+    ffi_support::call_with_result(error, || -> MgrResult<()> {
+        #[cfg(feature = "logins")]
+        {
+            let api = logins_ffi::ENGINES
+                .get_u64(_logins_handle, |api| -> Result<_, HandleError> {
+                    Ok(std::sync::Arc::clone(api))
+                })?;
+            sync_manager::set_logins(api);
+            Ok(())
+        }
+        #[cfg(not(feature = "logins"))]
+        {
+            log::error!("Sync manager not compiled with logins support");
+            Err(sync_manager::ErrorKind::UnsupportedFeature("logins".to_string()).into())
+        }
+    })
+}
+
+#[no_mangle]
+pub extern "C" fn sync_manager_disconnect(error: &mut ExternError) {
+    ffi_support::call_with_output(error, sync_manager::disconnect);
+}
+
+unsafe fn get_buffer<'a>(data: *const u8, len: i32) -> &'a [u8] {
+    assert!(len >= 0, "Bad buffer len: {}", len);
+    if len == 0 {
+        // This will still fail, but as a bad protobuf format.
+        &[]
+    } else {
+        assert!(!data.is_null(), "Unexpected null data pointer");
+        std::slice::from_raw_parts(data, len as usize)
+    }
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn sync_manager_sync(
+    params_data: *const u8,
+    params_len: i32,
+    error: &mut ExternError,
+) -> ffi_support::ByteBuffer {
+    ffi_support::call_with_result(error, || {
+        let buffer = get_buffer(params_data, params_len);
+        let params: sync_manager::msg_types::SyncParams = prost::Message::decode(buffer)?;
+        sync_manager::sync(params)
+    })
+}
+
+ffi_support::define_string_destructor!(sync_manager_destroy_string);
+ffi_support::define_bytebuffer_destructor!(sync_manager_destroy_bytebuffer);
diff --git a/components/sync_manager/src/error.rs b/components/sync_manager/src/error.rs
new file mode 100644
index 000000000..9326b398f
--- /dev/null
+++ b/components/sync_manager/src/error.rs
@@ -0,0 +1,25 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+use failure::Fail;
+
+#[derive(Debug, Fail)]
+pub enum ErrorKind {
+    #[fail(display = "Unknown engine: {}", _0)]
+    UnknownEngine(String),
+    #[fail(display = "Manager was compiled without support for {:?}", _0)]
+    UnsupportedFeature(String),
+    #[fail(display = "Database connection for '{}' is not open", _0)]
+    ConnectionClosed(String),
+    #[fail(display = "Handle is invalid: {}", _0)]
+    InvalidHandle(#[fail(cause)] ffi_support::HandleError),
+    #[fail(display = "Protobuf decode error: {}", _0)]
+    ProtobufDecodeError(#[fail(cause)] prost::DecodeError),
+}
+
+error_support::define_error! {
+    ErrorKind {
+        (InvalidHandle, ffi_support::HandleError),
+        (ProtobufDecodeError, prost::DecodeError),
+    }
+}
diff --git a/components/sync_manager/src/ffi.rs b/components/sync_manager/src/ffi.rs
new file mode 100644
index 000000000..1a2270030
--- /dev/null
+++ b/components/sync_manager/src/ffi.rs
@@ -0,0 +1,49 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use crate::error::{Error, ErrorKind};
+use ffi_support::{ErrorCode, ExternError};
+
+pub mod error_codes {
+    // Note: 0 (success) and -1 (panic) are reserved by ffi_support
+    pub const UNEXPECTED: i32 = 1;
+
+    /// We were asked to sync an engine, but we either don't know what it is,
+    /// or were compiled without support for it.
+    pub const UNSUPPORTED_ENGINE: i32 = 2;
+
+    /// We were asked to sync an engine which is not open (e.g. Weak::upgrade
+    /// returns None).
+    pub const ENGINE_NOT_OPEN: i32 = 3;
+}
+
+fn get_code(err: &Error) -> ErrorCode {
+    match err.kind() {
+        ErrorKind::UnknownEngine(e) => {
+            log::error!("Unknown engine: {}", e);
+            ErrorCode::new(error_codes::UNSUPPORTED_ENGINE)
+        }
+        ErrorKind::UnsupportedFeature(f) => {
+            log::error!("Unsupported feature: {}", f);
+            ErrorCode::new(error_codes::UNSUPPORTED_ENGINE)
+        }
+        ErrorKind::ConnectionClosed(e) => {
+            log::error!("Connection closed: {}", e);
+            ErrorCode::new(error_codes::ENGINE_NOT_OPEN)
+        }
+        err => {
+            log::error!("Unexpected error: {}", err);
+            ErrorCode::new(error_codes::UNEXPECTED)
+        }
+    }
+}
+
+impl From<Error> for ExternError {
+    fn from(e: Error) -> ExternError {
+        ExternError::new_error(get_code(&e), e.to_string())
+    }
+}
+
+ffi_support::implement_into_ffi_by_protobuf!(crate::msg_types::SyncResult);
+ffi_support::implement_into_ffi_by_protobuf!(crate::msg_types::SyncParams);
diff --git a/components/sync_manager/src/lib.rs b/components/sync_manager/src/lib.rs
new file mode 100644
index 000000000..1ef5381ee
--- /dev/null
+++ b/components/sync_manager/src/lib.rs
@@ -0,0 +1,53 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#![allow(unknown_lints)]
+#![warn(rust_2018_idioms)]
+
+pub mod error;
+mod ffi;
+mod manager;
+
+pub use error::{Error, ErrorKind, Result};
+
+pub mod msg_types {
+    include!(concat!(env!("OUT_DIR"), "/msg_types.rs"));
+}
+
+#[cfg(feature = "logins")]
+use logins::PasswordEngine;
+use manager::SyncManager;
+#[cfg(feature = "places")]
+use places::PlacesApi;
+#[cfg(any(feature = "places", feature = "logins"))]
+use std::sync::Arc;
+use std::sync::Mutex;
+
+lazy_static::lazy_static! {
+    static ref MANAGER: Mutex<SyncManager> = Mutex::new(SyncManager::new());
+}
+
+#[cfg(feature = "places")]
+pub fn set_places(places: Arc<PlacesApi>) {
+    let mut manager = MANAGER.lock().unwrap();
+    manager.set_places(places);
+}
+
+#[cfg(feature = "logins")]
+pub fn set_logins(places: Arc<Mutex<PasswordEngine>>) {
+    let mut manager = MANAGER.lock().unwrap();
+    manager.set_logins(places);
+}
+
+pub fn disconnect() {
+    let mut manager = MANAGER.lock().unwrap();
+    manager.disconnect();
+}
+
+pub fn sync(params: msg_types::SyncParams) -> Result<msg_types::SyncResult> {
+    let mut manager = MANAGER.lock().unwrap();
+    // TODO: translate the protobuf message into something nicer to work with in
+    // Rust.
+    manager.sync(params)
+}
diff --git a/components/sync_manager/src/manager.rs b/components/sync_manager/src/manager.rs
new file mode 100644
index 000000000..75a8cf601
--- /dev/null
+++ b/components/sync_manager/src/manager.rs
@@ -0,0 +1,71 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#[cfg(feature = "places")]
+use places::PlacesApi;
+// use sql_support::SqlInterruptHandle;
+use crate::error::*;
+use crate::msg_types::{SyncParams, SyncResult};
+#[cfg(feature = "logins")]
+use logins::PasswordEngine;
+#[cfg(feature = "logins")]
+use std::sync::Mutex;
+#[cfg(any(feature = "places", feature = "logins"))]
+use std::sync::{Arc, Weak};
+
+pub struct SyncManager {
+    #[cfg(feature = "places")]
+    places: Weak<PlacesApi>,
+    #[cfg(feature = "logins")]
+    logins: Weak<Mutex<PasswordEngine>>,
+}
+
+impl SyncManager {
+    pub fn new() -> Self {
+        Self {
+            #[cfg(feature = "places")]
+            places: Weak::new(),
+            #[cfg(feature = "logins")]
+            logins: Weak::new(),
+        }
+    }
+
+    #[cfg(feature = "places")]
+    pub fn set_places(&mut self, places: Arc<PlacesApi>) {
+        self.places = Arc::downgrade(&places);
+    }
+
+    #[cfg(feature = "logins")]
+    pub fn set_logins(&mut self, logins: Arc<Mutex<PasswordEngine>>) {
+        self.logins = Arc::downgrade(&logins);
+    }
+
+    pub fn disconnect(&mut self) {
+        unimplemented!();
+    }
+
+    pub fn sync(&mut self, params: SyncParams) -> Result<SyncResult> {
+        check_engine_list(&params.engines_to_sync)?;
+        unimplemented!();
+    }
+}
+
+fn check_engine_list(list: &[String]) -> Result<()> {
+    for e in list {
+        if e == "bookmarks" || e == "history" {
+            if cfg!(not(feature = "places")) {
+                return Err(ErrorKind::UnsupportedFeature(e.to_string()).into());
+            }
+            continue;
+        }
+        if e == "passwords" {
+            if cfg!(not(feature = "logins")) {
+                return Err(ErrorKind::UnsupportedFeature(e.to_string()).into());
+            }
+            continue;
+        }
+        return Err(ErrorKind::UnknownEngine(e.to_string()).into());
+    }
+    Ok(())
+}
diff --git a/components/sync_manager/src/manager_msg_types.proto b/components/sync_manager/src/manager_msg_types.proto
new file mode 100644
index 000000000..6a9e1e09a
--- /dev/null
+++ b/components/sync_manager/src/manager_msg_types.proto
@@ -0,0 +1,56 @@
+syntax = "proto2";
+
+// Note: this file name must be unique due to how the iOS megazord works :(
+
+package msg_types;
+
+option java_package = "mozilla.appservices.syncmanager";
+option java_outer_classname = "MsgTypes";
+
+enum SyncReason {
+    SCHEDULED = 1;
+    USER = 2;
+    PRE_SLEEP = 3;
+    STARTUP = 4;
+    ENABLED_CHANGE = 5;
+}
+
+message SyncParams {
+    repeated string engines_to_sync = 1;
+    required bool sync_all_engines = 2;
+
+    required SyncReason reason = 3;
+
+    map<string, bool> engines_to_change_state = 4;
+
+    optional string persisted_state = 5;
+
+    // These conceptually are a nested type, but exposing them as such would add
+    // needless complexity to the FFI.
+    required string acct_key_id = 6;
+    required string acct_access_token = 7;
+    required string acct_tokenserver_url = 8;
+    required string acct_sync_key = 9;
+}
+
+enum ServiceStatus {
+    OK = 1;
+    NETWORK_ERROR = 2;
+    SERVICE_ERROR = 3;
+    AUTH_ERROR = 4;
+    BACKED_OFF = 5;
+    OTHER_ERROR = 6;
+}
+
+message SyncResult {
+    required ServiceStatus status = 1;
+    map<string, string> results = 2; // empty string used for 'no error'
+
+    repeated string declined = 3;
+    // false if we didn't manage to check declined.
+    required bool have_declined = 4;
+
+    optional int64 next_sync_allowed_at = 5;
+    required string persisted_state = 6;
+    optional string telemetry_json = 7;
+}
diff --git a/megazords/fenix/Cargo.toml b/megazords/fenix/Cargo.toml
index 6fa529617..56c2c6c29 100644
--- a/megazords/fenix/Cargo.toml
+++ b/megazords/fenix/Cargo.toml
@@ -15,3 +15,4 @@ places-ffi = { path = "../../components/places/ffi" }
 push-ffi = { path = "../../components/push/ffi" }
 rc_log_ffi = { path = "../../components/rc_log" }
 viaduct = { path = "../../components/viaduct", default-features = false }
+sync_manager_ffi = { path = "../../components/sync_manager/ffi", features = ["places"] }
diff --git a/megazords/fenix/src/lib.rs b/megazords/fenix/src/lib.rs
index 4232613b8..9d4f9dca7 100644
--- a/megazords/fenix/src/lib.rs
+++ b/megazords/fenix/src/lib.rs
@@ -10,4 +10,5 @@ pub use logins_ffi;
 pub use places_ffi;
 pub use push_ffi;
 pub use rc_log_ffi;
+pub use sync_manager_ffi;
 pub use viaduct;
diff --git a/megazords/full/Cargo.toml b/megazords/full/Cargo.toml
index c666f1420..b037fe634 100644
--- a/megazords/full/Cargo.toml
+++ b/megazords/full/Cargo.toml
@@ -15,4 +15,5 @@ places-ffi = { path = "../../components/places/ffi" }
 push-ffi = { path = "../../components/push/ffi" }
 rc_log_ffi = { path = "../../components/rc_log" }
 viaduct = { path = "../../components/viaduct", default_features = false }
+sync_manager_ffi = { path = "../../components/sync_manager/ffi", features = ["logins", "places"] }
 lazy_static = "1.4.0"
diff --git a/megazords/full/src/lib.rs b/megazords/full/src/lib.rs
index a39517824..3943d4202 100644
--- a/megazords/full/src/lib.rs
+++ b/megazords/full/src/lib.rs
@@ -13,6 +13,7 @@ pub use logins_ffi;
 pub use places_ffi;
 pub use push_ffi;
 pub use rc_log_ffi;
+pub use sync_manager_ffi;
 pub use viaduct;
 
 /// In order to support the use case of consumers who don't know about megazords
diff --git a/megazords/lockbox/Cargo.toml b/megazords/lockbox/Cargo.toml
index 27f8a0fce..7e6f91010 100644
--- a/megazords/lockbox/Cargo.toml
+++ b/megazords/lockbox/Cargo.toml
@@ -13,3 +13,4 @@ fxaclient_ffi = { path = "../../components/fxa-client/ffi" }
 logins_ffi = { path = "../../components/logins/ffi" }
 rc_log_ffi = { path = "../../components/rc_log" }
 viaduct = { path = "../../components/viaduct", default-features = false }
+sync_manager_ffi = { path = "../../components/sync_manager/ffi", features = ["logins"] }
diff --git a/megazords/lockbox/src/lib.rs b/megazords/lockbox/src/lib.rs
index 51afae50b..7f267c96e 100644
--- a/megazords/lockbox/src/lib.rs
+++ b/megazords/lockbox/src/lib.rs
@@ -8,4 +8,5 @@
 pub use fxaclient_ffi;
 pub use logins_ffi;
 pub use rc_log_ffi;
+pub use sync_manager_ffi;
 pub use viaduct;