diff --git a/packages/types/src/clientreport.ts b/packages/types/src/clientreport.ts
new file mode 100644
index 000000000000..add2194c13ff
--- /dev/null
+++ b/packages/types/src/clientreport.ts
@@ -0,0 +1,7 @@
+import { SentryRequestType } from './request';
+import { Outcome } from './transport';
+
+export type ClientReport = {
+  timestamp: number;
+  discarded_events: { reason: Outcome; category: SentryRequestType; quantity: number };
+};
diff --git a/packages/types/src/envelope.ts b/packages/types/src/envelope.ts
index 27921bc1a097..2a70cea96667 100644
--- a/packages/types/src/envelope.ts
+++ b/packages/types/src/envelope.ts
@@ -1,70 +1,51 @@
+import { ClientReport } from './clientreport';
 import { Event } from './event';
-import { SentryRequestType } from './request';
 import { SdkInfo } from './sdkinfo';
 import { Session, SessionAggregates } from './session';
-import { Outcome } from './transport';
-import { User } from './user';
+import { UserFeedback } from './user';
 
 // Based on: https://develop.sentry.dev/sdk/envelopes/
 
-type CommonEnvelopeHeaders = {
+export type BaseEnvelopeHeaders = {
+  [key: string]: unknown;
   dsn?: string;
   sdk?: SdkInfo;
 };
 
-type CommonEnvelopeItemHeaders = {
+export type BaseEnvelopeItemHeaders = {
+  [key: string]: unknown;
+  type: string;
   length?: number;
 };
 
-/**
- * 1st Item: Item headers
- * 2nd Item: Item payload
- */
-type BaseEnvelopeItem<ItemHeader extends { type: string }, Payload = unknown> = [
-  CommonEnvelopeItemHeaders & ItemHeader,
-  Payload,
-];
-
-type UnknownEnvelopeItem = BaseEnvelopeItem<{ type: '__unknown__' }>;
-
-type BaseEnvelope<
-  EnvelopeHeaders extends Record<string, unknown>,
-  EnvelopeItem extends BaseEnvelopeItem<{ type: string }>,
-> = {
-  headers: CommonEnvelopeHeaders & EnvelopeHeaders;
-  items: Array<EnvelopeItem | UnknownEnvelopeItem>;
-};
-
-export type EventEnvelopeItem = BaseEnvelopeItem<{ type: 'event' | 'transaction' }, Event>;
-
-type AttachmentEnvelopeItem = BaseEnvelopeItem<{ type: 'attachment'; filename: 'string' }>;
-
-type UserFeedbackEnvelopeItem = BaseEnvelopeItem<
-  { type: 'user_report' },
-  {
-    event_id: string;
-    email: User['email'];
-    name: string;
-    comments: string;
-  }
->;
-
-export type EventEnvelope = BaseEnvelope<
-  { event_id: string; sent_at: string },
-  EventEnvelopeItem | AttachmentEnvelopeItem | UserFeedbackEnvelopeItem
->;
-
-export type SessionEnvelopeItem =
-  | BaseEnvelopeItem<{ type: 'session' }, Session>
-  | BaseEnvelopeItem<{ type: 'sessions' }, SessionAggregates>;
-
-export type SessionEnvelope = BaseEnvelope<{ sent_at: string }, SessionEnvelopeItem>;
-
-export type ClientReportEnvelopeItem = BaseEnvelopeItem<
-  { type: 'client_report' },
-  { timestamp: number; discarded_events: { reason: Outcome; category: SentryRequestType; quantity: number } }
->;
-
-export type ClientReportEnvelope = BaseEnvelope<Record<string, unknown>, ClientReportEnvelopeItem>;
+export type BaseEnvelopeItem<IH extends BaseEnvelopeItemHeaders, P extends unknown> = [IH, P]; // P is for payload
+
+export type BaseEnvelope<
+  EH extends BaseEnvelopeHeaders,
+  I extends BaseEnvelopeItem<BaseEnvelopeItemHeaders, unknown>,
+> = [EH, I[]];
+
+type EventItemHeaders = { type: 'event' | 'transaction' };
+type AttachmentItemHeaders = { type: 'attachment'; filename: string };
+type UserFeedbackItemHeaders = { type: 'user_report' };
+type SessionItemHeaders = { type: 'session' };
+type SessionAggregatesItemHeaders = { type: 'sessions' };
+type ClientReportItemHeaders = { type: 'client_report' };
+
+export type EventItem = BaseEnvelopeItem<EventItemHeaders, Event>;
+export type AttachmentItem = BaseEnvelopeItem<AttachmentItemHeaders, unknown>;
+export type UserFeedbackItem = BaseEnvelopeItem<UserFeedbackItemHeaders, UserFeedback>;
+export type SessionItem =
+  | BaseEnvelopeItem<SessionItemHeaders, Session>
+  | BaseEnvelopeItem<SessionAggregatesItemHeaders, SessionAggregates>;
+export type ClientReportItem = BaseEnvelopeItem<ClientReportItemHeaders, ClientReport>;
+
+type EventEnvelopeHeaders = { event_id: string; sent_at: string };
+type SessionEnvelopeHeaders = { sent_at: string };
+type ClientReportEnvelopeHeaders = BaseEnvelopeHeaders;
+
+export type EventEnvelope = BaseEnvelope<EventEnvelopeHeaders, EventItem | AttachmentItem | UserFeedbackItem>;
+export type SessionEnvelope = BaseEnvelope<SessionEnvelopeHeaders, SessionItem>;
+export type ClientReportEnvelope = BaseEnvelope<ClientReportEnvelopeHeaders, ClientReportItem>;
 
 export type Envelope = EventEnvelope | SessionEnvelope | ClientReportEnvelope;
diff --git a/packages/types/src/index.ts b/packages/types/src/index.ts
index 818f50759fa0..996f53c4c685 100644
--- a/packages/types/src/index.ts
+++ b/packages/types/src/index.ts
@@ -1,16 +1,23 @@
 export { Breadcrumb, BreadcrumbHint } from './breadcrumb';
 export { Client } from './client';
+export { ClientReport } from './clientreport';
 export { Context, Contexts } from './context';
 export { DsnComponents, DsnLike, DsnProtocol } from './dsn';
 export { DebugImage, DebugImageType, DebugMeta } from './debugMeta';
 export {
+  AttachmentItem,
+  BaseEnvelope,
+  BaseEnvelopeHeaders,
+  BaseEnvelopeItem,
+  BaseEnvelopeItemHeaders,
   ClientReportEnvelope,
-  ClientReportEnvelopeItem,
+  ClientReportItem,
   Envelope,
   EventEnvelope,
-  EventEnvelopeItem,
+  EventItem,
   SessionEnvelope,
-  SessionEnvelopeItem,
+  SessionItem,
+  UserFeedbackItem,
 } from './envelope';
 export { ExtendedError } from './error';
 export { Event, EventHint } from './event';
@@ -58,5 +65,5 @@ export {
 } from './transaction';
 export { Thread } from './thread';
 export { Outcome, Transport, TransportOptions, TransportClass } from './transport';
-export { User } from './user';
+export { User, UserFeedback } from './user';
 export { WrappedFunction } from './wrappedfunction';
diff --git a/packages/types/src/user.ts b/packages/types/src/user.ts
index eae46b008b3e..0f27df252cf6 100644
--- a/packages/types/src/user.ts
+++ b/packages/types/src/user.ts
@@ -6,3 +6,10 @@ export interface User {
   email?: string;
   username?: string;
 }
+
+export interface UserFeedback {
+  event_id: string;
+  email: User['email'];
+  name: string;
+  comments: string;
+}