diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5105690..0c8347b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,18 +6,25 @@ This file is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 
-## UNRELEASED
+## [2.5.0] - 2023-12-31
 
 ### Added:
-  - Added `mapKey` method to both iterables
-  - Added `mapValue` method to both iterables
   - Added `duplicate` method to both iterables
 
 ### Changed:
   - Improved types of `toObject` and `toMap` methods
+  - Improved performance of `PolySyncIterable#map` and `PolySyncIterable#filter`
+
+
+## [2.4.0] - 2023-07-04
+
+### Added:
+  - Added `mapKey` method to both iterables
+  - Added `mapValue` method to both iterables
+
+### Changed:
   - Added an `options` argument to `PolyAsyncIterable#complete`
   - Added an `options` argument to `PolyAsyncIterable#join`
-  - Improved performance of `PolySyncIterable#map` and `PolySyncIterable#filter`
 
 
 ## [2.3.0] - 2023-03-16
diff --git a/docs/polyethylene.baseimpls.md b/docs/polyethylene.baseimpls.md
deleted file mode 100644
index fca414e..0000000
--- a/docs/polyethylene.baseimpls.md
+++ /dev/null
@@ -1,11 +0,0 @@
-<!-- Do not edit this file. It is automatically generated by API Documenter. -->
-
-[Home](./index.md) &gt; [polyethylene](./polyethylene.md) &gt; [baseImpls](./polyethylene.baseimpls.md)
-
-## baseImpls variable
-
-**Signature:**
-
-```typescript
-baseImpls: BaseImpls
-```
diff --git a/docs/polyethylene.md b/docs/polyethylene.md
index 62031bd..f6f38f8 100644
--- a/docs/polyethylene.md
+++ b/docs/polyethylene.md
@@ -35,12 +35,6 @@ The entry point for this library is the [Poly](./polyethylene.poly.md) namespace
 |  --- | --- |
 |  [Poly](./polyethylene.poly.md) | Main namespace for the creation of [PolySyncIterable](./polyethylene.polysynciterable.md) and [PolyAsyncIterable](./polyethylene.polyasynciterable.md) objects. |
 
-## Variables
-
-|  Variable | Description |
-|  --- | --- |
-|  [baseImpls](./polyethylene.baseimpls.md) |  |
-
 ## Type Aliases
 
 |  Type Alias | Description |
diff --git a/etc/polyethylene.api.json b/etc/polyethylene.api.json
index 7e84dfb..1cc832d 100644
--- a/etc/polyethylene.api.json
+++ b/etc/polyethylene.api.json
@@ -693,30 +693,6 @@
             }
           ]
         },
-        {
-          "kind": "Variable",
-          "canonicalReference": "polyethylene!baseImpls:var",
-          "docComment": "",
-          "excerptTokens": [
-            {
-              "kind": "Content",
-              "text": "baseImpls: "
-            },
-            {
-              "kind": "Reference",
-              "text": "BaseImpls",
-              "canonicalReference": "polyethylene!~BaseImpls:interface"
-            }
-          ],
-          "fileUrlPath": "src/lib/sync/poly-sync-iterable.ts",
-          "isReadonly": true,
-          "releaseTag": "Public",
-          "name": "baseImpls",
-          "variableTypeTokenRange": {
-            "startIndex": 1,
-            "endIndex": 2
-          }
-        },
         {
           "kind": "TypeAlias",
           "canonicalReference": "polyethylene!ChunkingPredicate:type",
diff --git a/etc/polyethylene.api.md b/etc/polyethylene.api.md
index c7f80ea..4b122d7 100644
--- a/etc/polyethylene.api.md
+++ b/etc/polyethylene.api.md
@@ -30,11 +30,6 @@ export class AsyncIterableBuilder<T> implements AsyncIterable<T> {
     value(obj: T): void;
 }
 
-// Warning: (ae-forgotten-export) The symbol "BaseImpls" needs to be exported by the entry point main.d.ts
-//
-// @public (undocumented)
-export const baseImpls: BaseImpls;
-
 // @public
 export type ChunkingPredicate<T> = (elem: T, lastElem: T, firstElem: T) => boolean;
 
@@ -62,15 +57,6 @@ export type IndexedRunnable<T> = (elem: T, index: number) => void;
 // @public
 export type IndexedTypePredicate<T, U extends T> = (elem: T, index: number) => elem is U;
 
-// Warning: (ae-internal-missing-underscore) The name "IterablePolySyncIterable" should be prefixed with an underscore because the declaration is marked as @internal
-//
-// @internal
-export class IterablePolySyncIterable<T> extends PolySyncIterable<T> {
-    // (undocumented)
-    [Symbol.iterator](): Iterator<T, void, undefined>;
-    constructor(iterable: Iterable<T>);
-}
-
 // @public
 namespace Poly {
     function asyncFrom<T>(iterableOrFactory: Iterable<T> | IterableFactory<T> | AsyncIterable<T> | AsyncIterableFactory<T>): PolyAsyncIterable<T>;
diff --git a/package.json b/package.json
index 4919660..9805fa3 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "polyethylene",
-  "version": "2.4.0",
+  "version": "2.5.0",
   "description": "Functional programming for iterables and async iterables",
   "author": "Daniel Escoz <darkhogg+npm.polyethylene@gmail.com>",
   "license": "MIT",
diff --git a/src/lib/main.ts b/src/lib/main.ts
index d2263e2..e702c19 100644
--- a/src/lib/main.ts
+++ b/src/lib/main.ts
@@ -17,7 +17,6 @@ import PolyAsyncIterable from './async/poly-iterable.js'
 export default Poly
 export {Poly, PolySyncIterable, PolyAsyncIterable, AsyncIterableBuilder}
 
-export type * from './sync/poly-sync-iterable.js'
 export type * from './async/poly-iterable.js'
 
 export type * from './types.js'
diff --git a/src/lib/sync/poly-sync-iterable.ts b/src/lib/sync/poly-sync-iterable.ts
index 8bfaa35..57210ab 100644
--- a/src/lib/sync/poly-sync-iterable.ts
+++ b/src/lib/sync/poly-sync-iterable.ts
@@ -36,11 +36,13 @@ import PolyAsyncIterable from '../async/poly-iterable.js'
 import type MapSyncIterable from './map-sync-iterable.js'
 import FilterSyncIterable from './filter-sync-iterable.js'
 
-/* default implementatios -- undefined here to prevent circular dependencies */
+/* default implementations -- undefined here to prevent circular dependencies */
+/** @internal */
 interface BaseImpls {
   map: typeof MapSyncIterable.create
   filter: typeof FilterSyncIterable.create
 }
+/** @internal */
 export const baseImpls = {} as BaseImpls