diff --git a/Package.swift b/Package.swift
index a1562d76..56417e84 100644
--- a/Package.swift
+++ b/Package.swift
@@ -16,7 +16,7 @@ let package = Package(
     .library(name: "_CAsyncSequenceValidationSupport", type: .static, targets: ["AsyncSequenceValidation"]),
     .library(name: "AsyncAlgorithms_XCTest", targets: ["AsyncAlgorithms_XCTest"]),
   ],
-  dependencies: [.package(url: "https://github.com/apple/swift-collections.git", .upToNextMajor(from: "1.0.3"))],
+  dependencies: [.package(url: "https://github.com/apple/swift-collections.git", .upToNextMajor(from: "1.0.4"))],
   targets: [
     .target(
       name: "AsyncAlgorithms",
diff --git a/Sources/AsyncAlgorithms/Buffer/BoundedBufferStateMachine.swift b/Sources/AsyncAlgorithms/Buffer/BoundedBufferStateMachine.swift
index a5c50a61..b863bc50 100644
--- a/Sources/AsyncAlgorithms/Buffer/BoundedBufferStateMachine.swift
+++ b/Sources/AsyncAlgorithms/Buffer/BoundedBufferStateMachine.swift
@@ -16,7 +16,7 @@ struct BoundedBufferStateMachine<Base: AsyncSequence> {
   typealias SuspendedProducer = UnsafeContinuation<Void, Never>
   typealias SuspendedConsumer = UnsafeContinuation<Result<Base.Element, Error>?, Never>
 
-  private enum State {
+  fileprivate enum State {
     case initial(base: Base)
     case buffering(
       task: Task<Void, Never>,
@@ -308,3 +308,6 @@ struct BoundedBufferStateMachine<Base: AsyncSequence> {
     }
   }
 }
+
+extension BoundedBufferStateMachine: Sendable where Base: Sendable { }
+extension BoundedBufferStateMachine.State: Sendable where Base: Sendable { }
diff --git a/Sources/AsyncAlgorithms/Buffer/UnboundedBufferStateMachine.swift b/Sources/AsyncAlgorithms/Buffer/UnboundedBufferStateMachine.swift
index b163619a..a43c2023 100644
--- a/Sources/AsyncAlgorithms/Buffer/UnboundedBufferStateMachine.swift
+++ b/Sources/AsyncAlgorithms/Buffer/UnboundedBufferStateMachine.swift
@@ -21,7 +21,7 @@ struct UnboundedBufferStateMachine<Base: AsyncSequence> {
     case bufferingOldest(Int)
   }
 
-  private enum State {
+  fileprivate enum State {
     case initial(base: Base)
     case buffering(
       task: Task<Void, Never>,
@@ -248,3 +248,6 @@ struct UnboundedBufferStateMachine<Base: AsyncSequence> {
     }
   }
 }
+
+extension UnboundedBufferStateMachine: Sendable where Base: Sendable { }
+extension UnboundedBufferStateMachine.State: Sendable where Base: Sendable { }
diff --git a/Sources/AsyncAlgorithms/Channels/AsyncChannel.swift b/Sources/AsyncAlgorithms/Channels/AsyncChannel.swift
index 75becf2d..8035d06a 100644
--- a/Sources/AsyncAlgorithms/Channels/AsyncChannel.swift
+++ b/Sources/AsyncAlgorithms/Channels/AsyncChannel.swift
@@ -19,7 +19,7 @@
 /// on the `Iterator` is made, or when `finish()` is called from another Task.
 /// As `finish()` induces a terminal state, there is no more need for a back pressure management.
 /// This function does not suspend and will finish all the pending iterations.
-public final class AsyncChannel<Element>: AsyncSequence, @unchecked Sendable {
+public final class AsyncChannel<Element: Sendable>: AsyncSequence, @unchecked Sendable {
   public typealias Element = Element
   public typealias AsyncIterator = Iterator
 
diff --git a/Sources/AsyncAlgorithms/Channels/AsyncThrowingChannel.swift b/Sources/AsyncAlgorithms/Channels/AsyncThrowingChannel.swift
index 28de36ae..2fc48dfe 100644
--- a/Sources/AsyncAlgorithms/Channels/AsyncThrowingChannel.swift
+++ b/Sources/AsyncAlgorithms/Channels/AsyncThrowingChannel.swift
@@ -18,7 +18,7 @@
 /// and is resumed when the next call to `next()` on the `Iterator` is made, or when `finish()`/`fail(_:)` is called
 /// from another Task. As `finish()` and `fail(_:)` induce a terminal state, there is no more need for a back pressure management.
 /// Those functions do not suspend and will finish all the pending iterations.
-public final class AsyncThrowingChannel<Element, Failure: Error>: AsyncSequence, @unchecked Sendable {
+public final class AsyncThrowingChannel<Element: Sendable, Failure: Error>: AsyncSequence, @unchecked Sendable {
   public typealias Element = Element
   public typealias AsyncIterator = Iterator
 
diff --git a/Sources/AsyncAlgorithms/Channels/ChannelStateMachine.swift b/Sources/AsyncAlgorithms/Channels/ChannelStateMachine.swift
index 2972c754..e823e5f7 100644
--- a/Sources/AsyncAlgorithms/Channels/ChannelStateMachine.swift
+++ b/Sources/AsyncAlgorithms/Channels/ChannelStateMachine.swift
@@ -10,8 +10,11 @@
 //===----------------------------------------------------------------------===//
 @_implementationOnly import OrderedCollections
 
-struct ChannelStateMachine<Element, Failure: Error>: Sendable {
-  private struct SuspendedProducer: Hashable {
+// NOTE: this is only marked as unchecked since the swift-collections tag is before auditing for Sendable
+extension OrderedSet: @unchecked Sendable where Element: Sendable { }
+
+struct ChannelStateMachine<Element: Sendable, Failure: Error>: Sendable {
+  private struct SuspendedProducer: Hashable, Sendable {
     let id: UInt64
     let continuation: UnsafeContinuation<Void, Never>?
     let element: Element?
@@ -29,7 +32,7 @@ struct ChannelStateMachine<Element, Failure: Error>: Sendable {
     }
   }
 
-  private struct SuspendedConsumer: Hashable {
+  private struct SuspendedConsumer: Hashable, Sendable {
     let id: UInt64
     let continuation: UnsafeContinuation<Element?, any Error>?
 
@@ -51,7 +54,7 @@ struct ChannelStateMachine<Element, Failure: Error>: Sendable {
     case failed(Error)
   }
 
-  private enum State {
+  private enum State: Sendable {
     case channeling(
       suspendedProducers: OrderedSet<SuspendedProducer>,
       cancelledProducers: Set<SuspendedProducer>,
diff --git a/Sources/AsyncAlgorithms/Channels/ChannelStorage.swift b/Sources/AsyncAlgorithms/Channels/ChannelStorage.swift
index da398dbc..12b5ba72 100644
--- a/Sources/AsyncAlgorithms/Channels/ChannelStorage.swift
+++ b/Sources/AsyncAlgorithms/Channels/ChannelStorage.swift
@@ -8,7 +8,7 @@
 // See https://swift.org/LICENSE.txt for license information
 //
 //===----------------------------------------------------------------------===//
-struct ChannelStorage<Element, Failure: Error>: Sendable {
+struct ChannelStorage<Element: Sendable, Failure: Error>: Sendable {
   private let stateMachine: ManagedCriticalState<ChannelStateMachine<Element, Failure>>
   private let ids = ManagedCriticalState<UInt64>(0)