diff --git a/types/sharedb/index.d.ts b/types/sharedb/index.d.ts
index 0f0f5575fd..2f78d1d3dc 100644
--- a/types/sharedb/index.d.ts
+++ b/types/sharedb/index.d.ts
@@ -1,7 +1,9 @@
 // Type definitions for sharedb 1.0
 // Project: https://github.com/share/sharedb
 // Definitions by: Steve Oney <https://github.com/soney>
+//                 Eric Hwang <https://github.com/ericyhwang>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+// TypeScript Version: 2.1
 
 /// <reference path="lib/sharedb.d.ts" />
 
@@ -18,20 +20,33 @@ export = sharedb;
 
 declare class sharedb {
     constructor(options?: {db?: any, pubsub?: sharedb.PubSub, disableDocAction?: boolean, disableSpaceDelimitedActions?: boolean});
-    connect: () => sharedb.Connection;
-    addProjection(name: string, collection: string, fields: {}): any;
+    connect: (connection?: any, req?: any) => sharedb.Connection;
+    /**
+     * Registers a projection that can be used from clients just like a normal collection.
+     *
+     * @param name name of the projection
+     * @param collection name of the backing collection
+     * @param fields field whitelist for the projection
+     */
+    addProjection(name: string, collection: string, fields: ProjectionFields): void;
     listen(stream: any): void;
-    close(callback?: (err: Error) => any): void;
-    use(action: sharedb.UseAction, fn: sharedb.UseCallback): void;
+    close(callback?: (err?: Error) => any): void;
+    /**
+     * Registers a server middleware function.
+     *
+     * @param action name of an action from https://github.com/share/sharedb#middlewares
+     * @param fn listener invoked when the specified action occurs
+     */
+    use<A extends keyof middleware.ActionContextMap>(
+        action: A,
+        fn: (context: middleware.ActionContextMap[A], callback: (err?: any) => void) => void,
+    ): void;
     static types: {
         register: (type: { name?: string, uri?: string, [key: string]: any}) => void;
     };
 }
 
 declare namespace sharedb {
-    type UseAction = 'connect' | 'op' | 'doc' | 'query' | 'submit' | 'apply' | 'commit' | 'after submit' | 'receive';
-    type UseCallback = ((request: {action: UseAction, agent: any, req: any, collection: string, id: string, query: any, op: ShareDB.RawOp}, callback: () => void) => void);
-
     abstract class DB {
         projectsSnapshots: boolean;
         disableSubscribe: boolean;
@@ -100,3 +115,108 @@ declare namespace sharedb {
     type Path = ShareDB.Path;
     type ShareDBSourceOptions = ShareDB.ShareDBSourceOptions;
 }
+
+declare namespace middleware {
+    interface ActionContextMap {
+        afterSubmit: SubmitContext;
+        apply: ApplyContext;
+        commit: CommitContext;
+        connect: ConnectContext;
+        doc: DocContext;  // Deprecated, use 'readSnapshots' instead.
+        op: OpContext;
+        query: QueryContext;
+        readSnapshots: ReadSnapshotsContext;
+        receive: ReceiveContext;
+        reply: ReplyContext;
+        submit: SubmitContext;
+    }
+
+    interface BaseContext {
+        action: keyof ActionContextMap;
+        agent: any;
+        backend: sharedb;
+    }
+
+    interface ApplyContext extends BaseContext, SubmitRequest {
+    }
+
+    interface CommitContext extends BaseContext, SubmitRequest {
+    }
+
+    interface ConnectContext extends BaseContext {
+        stream: any;
+        req: any;  // Property always exists, value may be undefined
+    }
+
+    interface DocContext extends BaseContext {
+        collection: string;
+        id: string;
+        snapshot: ShareDB.Snapshot;
+    }
+
+    interface OpContext extends BaseContext {
+        collection: string;
+        id: string;
+        op: ShareDB.Op;
+    }
+
+    interface QueryContext extends BaseContext {
+        index: string;
+        collection: string;
+        projection: Projection | undefined;
+        fields: ProjectionFields | undefined;
+        channel: string;
+        query: ShareDB.JSONObject;
+        options: ShareDB.JSONObject;
+        db: sharedb.DB | null;
+        snapshotProjection: Projection | null;
+    }
+
+    interface ReadSnapshotsContext extends BaseContext {
+        collection: string;
+        snapshots: ShareDB.Snapshot[];
+        snapshotType: SnapshotType;
+    }
+
+    interface ReceiveContext extends BaseContext {
+        data: ShareDB.JSONObject;  // ClientRequest, but before any validation
+    }
+
+    interface ReplyContext extends BaseContext {
+        request: ShareDB.ClientRequest;
+        reply: ShareDB.JSONObject;
+    }
+
+    type SnapshotType = 'current' | 'byVersion' | 'byTimestamp';
+
+    interface SubmitContext extends BaseContext, SubmitRequest {
+    }
+}
+
+interface Projection {
+    target: string;
+    fields: ProjectionFields;
+}
+
+interface ProjectionFields {
+    [propertyName: string]: true;
+}
+
+interface SubmitRequest {
+    index: string;
+    projection: Projection | undefined;
+    collection: string;
+    id: string;
+    op: sharedb.Op;
+    options: any;
+    start: number;
+
+    saveMilestoneSnapshot: boolean | null;
+    suppressPublish: boolean | null;
+    maxRetries: number | null;
+    retries: number;
+
+    snapshot: ShareDB.Snapshot | null;
+    ops: ShareDB.Op[];
+    channels: string[] | null;
+}
diff --git a/types/sharedb/lib/sharedb.d.ts b/types/sharedb/lib/sharedb.d.ts
index 426eac5a0e..01eace14c6 100644
--- a/types/sharedb/lib/sharedb.d.ts
+++ b/types/sharedb/lib/sharedb.d.ts
@@ -1,7 +1,26 @@
 import { EventEmitter } from 'events';
 
+export type JSONValue = string | number | boolean | null | JSONObject | JSONArray;
+export interface JSONObject {
+  [name: string]: JSONValue;
+}
+export interface JSONArray extends Array<JSONValue> {}
+
 export type Path = ReadonlyArray<string|number>;
-export type Snapshot = number;
+export interface Snapshot {
+    id: string;
+    v: number;
+    type: string | null;
+    data: JSONObject | undefined;
+    m: SnapshotMeta | null;
+}
+
+export interface SnapshotMeta {
+    ctime: number;
+    mtime: number;
+    // Users can use server middleware to add additional metadata to snapshots.
+    [key: string]: JSONValue;
+}
 
 export interface AddNumOp { p: Path; na: number; }
 
@@ -83,3 +102,12 @@ export class Query extends EventEmitter {
     removeListener(event: QueryEvent, listener: (...args: any[]) => any): this;
     destroy(): void;
 }
+
+export type RequestAction = 'qf' | 'qs' | 'qu' | 'bf' | 'bs' | 'bu' | 'f' | 's' | 'u' | 'op' | 'nf' | 'nt';
+
+export interface ClientRequest {
+    /** Short name of the request's action */
+    a: RequestAction;
+
+    [propertyName: string]: JSONValue;
+}
diff --git a/types/sharedb/sharedb-tests.ts b/types/sharedb/sharedb-tests.ts
index 55c3dc797d..da4e5ed948 100644
--- a/types/sharedb/sharedb-tests.ts
+++ b/types/sharedb/sharedb-tests.ts
@@ -30,7 +30,104 @@ class WebSocketJSONStream extends Duplex {
 }
 
 const backend = new ShareDB();
+
+backend.addProjection('notes_minimal', 'notes', {title: true, creator: true, lastUpdateTime: true});
+
+// Exercise middleware (backend.use)
+type SubmitRelatedActions = 'afterSubmit' | 'apply' | 'commit' | 'submit';
+const submitRelatedActions: SubmitRelatedActions[] = ['afterSubmit', 'apply', 'commit', 'submit'];
+for (const action of submitRelatedActions) {
+    backend.use(action, (request, callback) => {
+        console.log(
+            request.action,
+            request.agent,
+            request.backend,
+            request.index,
+            request.collection,
+            request.projection,
+            request.id,
+            request.op,
+            request.options,
+            request.snapshot,
+            request.ops,
+            request.channels,
+        );
+        callback();
+    });
+}
+backend.use('connect', (context, callback) => {
+    console.log(
+        context.action,
+        context.agent,
+        context.backend,
+        context.stream,
+        context.req,
+    );
+    callback();
+});
+backend.use('op', (context, callback) => {
+    console.log(
+        context.action,
+        context.agent,
+        context.backend,
+        context.collection,
+        context.id,
+        context.op,
+    );
+    callback();
+});
+backend.use('query', (context, callback) => {
+    console.log(
+        context.action,
+        context.agent,
+        context.backend,
+        context.index,
+        context.collection,
+        context.projection,
+        context.fields,
+        context.channel,
+        context.query,
+        context.options,
+        context.snapshotProjection,
+    );
+    callback();
+});
+backend.use('receive', (context, callback) => {
+    console.log(
+        context.action,
+        context.agent,
+        context.backend,
+        context.data,
+    );
+    callback();
+});
+backend.use('reply', (context, callback) => {
+    console.log(
+        context.action,
+        context.agent,
+        context.backend,
+        context.request,
+        context.reply,
+    );
+    callback();
+});
+backend.use('readSnapshots', (context, callback) => {
+    console.log(
+        context.action,
+        context.agent,
+        context.backend,
+        context.collection,
+        context.snapshots,
+        context.snapshotType,
+    );
+    callback();
+});
+
 const connection = backend.connect();
+const netRequest = {};  // Passed through to 'connect' middleware, not used by sharedb itself
+const connectionWithReq = backend.connect(null, netRequest);
+const reboundConnection = backend.connect(backend.connect(), netRequest);
+
 const doc = connection.get('examples', 'counter');
 
 doc.fetch((err) => {