diff --git a/CHANGELOG.md b/CHANGELOG.md
index 56ce8d8..c6981fb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,20 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- Added `StorageBackend` protocol/interface for backend-agnostic storage (#33)
+- Added `health_check()` method to storage backend with `/health` endpoint integration (#33)
+- Added `verify_integrity()` method for post-upload hash validation (#33)
+- Added garbage collection endpoint `POST /api/v1/admin/garbage-collect` for orphaned artifacts (#36)
+- Added orphaned artifacts listing endpoint `GET /api/v1/admin/orphaned-artifacts` (#36)
+- Added global storage statistics endpoint `GET /api/v1/stats` (#34)
+- Added storage breakdown endpoint `GET /api/v1/stats/storage` (#34)
+- Added deduplication metrics endpoint `GET /api/v1/stats/deduplication` (#34)
+- Added per-project statistics endpoint `GET /api/v1/projects/{project}/stats` (#34)
+- Added pytest infrastructure with mock S3 client for unit testing (#35)
+- Added unit tests for SHA256 hash calculation (#35)
+- Added unit tests for duplicate detection and deduplication behavior (#35)
+- Added test dependencies to requirements.txt (pytest, pytest-asyncio, pytest-cov, httpx, moto) (#35)
 ### Fixed
 - Fixed Helm chart `minio.ingress` conflicting with Bitnami MinIO subchart by renaming to `minioIngress` (#48)