diff --git a/hpc_server_openapi.json b/hpc_server_openapi.json
index 5a1d98c..64dbc1e 100644
--- a/hpc_server_openapi.json
+++ b/hpc_server_openapi.json
@@ -23,6 +23,18 @@
     {
       "name": "Applications",
       "description": "Application definition CRUD and job submission"
+    },
+    {
+      "name": "File Uploads",
+      "description": "Chunked file upload with SHA256 dedup, breakpoint resume, and instant upload"
+    },
+    {
+      "name": "Files",
+      "description": "File listing, metadata, download (with Range support), and deletion"
+    },
+    {
+      "name": "Folders",
+      "description": "Folder CRUD with materialized path hierarchy"
     }
   ],
   "paths": {
@@ -1103,6 +1115,649 @@
           }
         }
       }
+    },
+    "/files/uploads": {
+      "post": {
+        "tags": ["File Uploads"],
+        "operationId": "initUpload",
+        "summary": "Initialize a chunked upload session",
+        "description": "Creates an upload session for chunked file upload. If a file with the same SHA256 already exists, returns the existing file immediately (instant upload / dedup).",
+        "requestBody": {
+          "required": true,
+          "content": {
+            "application/json": {
+              "schema": {
+                "$ref": "#/components/schemas/InitUploadRequest"
+              }
+            }
+          }
+        },
+        "responses": {
+          "201": {
+            "description": "Upload session created",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/UploadSessionResponse"
+                }
+              }
+            }
+          },
+          "200": {
+            "description": "Dedup hit - file already exists, returns existing file",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/FileResponse"
+                }
+              }
+            }
+          },
+          "400": {
+            "description": "Invalid request",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files/uploads/{sessionId}/chunks/{chunkIndex}": {
+      "put": {
+        "tags": ["File Uploads"],
+        "operationId": "uploadChunk",
+        "summary": "Upload a single chunk",
+        "description": "Uploads a file chunk for the specified session. Chunks can be uploaded in any order and are idempotent.",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/SessionId"
+          },
+          {
+            "$ref": "#/components/parameters/ChunkIndex"
+          }
+        ],
+        "requestBody": {
+          "required": true,
+          "content": {
+            "multipart/form-data": {
+              "schema": {
+                "type": "object",
+                "required": ["chunk"],
+                "properties": {
+                  "chunk": {
+                    "type": "string",
+                    "format": "binary",
+                    "description": "File chunk data"
+                  }
+                }
+              }
+            }
+          }
+        },
+        "responses": {
+          "200": {
+            "description": "Chunk uploaded successfully"
+          },
+          "400": {
+            "description": "Invalid request",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "Upload session not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files/uploads/{sessionId}/complete": {
+      "post": {
+        "tags": ["File Uploads"],
+        "operationId": "completeUpload",
+        "summary": "Complete an upload session",
+        "description": "Finalizes the upload by merging all chunks via ComposeObject. Supports retry if previously failed.",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/SessionId"
+          }
+        ],
+        "responses": {
+          "201": {
+            "description": "Upload completed, returns file",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/FileResponse"
+                }
+              }
+            }
+          },
+          "400": {
+            "description": "Invalid request or missing chunks",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "Upload session not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files/uploads/{sessionId}": {
+      "get": {
+        "tags": ["File Uploads"],
+        "operationId": "getUploadStatus",
+        "summary": "Get upload session status",
+        "description": "Returns the current status of an upload session including list of uploaded chunk indices.",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/SessionId"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Upload session status",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/UploadSessionResponse"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "Upload session not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      },
+      "delete": {
+        "tags": ["File Uploads"],
+        "operationId": "cancelUpload",
+        "summary": "Cancel an upload session",
+        "description": "Cancels an in-progress upload, deletes uploaded chunks from MinIO, and removes the session.",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/SessionId"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Upload cancelled successfully"
+          },
+          "404": {
+            "description": "Upload session not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files": {
+      "get": {
+        "tags": ["Files"],
+        "operationId": "listFiles",
+        "summary": "List files with pagination",
+        "parameters": [
+          {
+            "name": "page",
+            "in": "query",
+            "schema": { "type": "integer", "default": 1 }
+          },
+          {
+            "name": "page_size",
+            "in": "query",
+            "schema": { "type": "integer", "default": 20 }
+          },
+          {
+            "name": "folder_id",
+            "in": "query",
+            "required": false,
+            "description": "Filter by folder ID",
+            "schema": { "type": "integer", "format": "int64" }
+          },
+          {
+            "name": "search",
+            "in": "query",
+            "required": false,
+            "description": "Search files by name",
+            "schema": { "type": "string" }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "List of files",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/FileListResponse"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files/{id}": {
+      "get": {
+        "tags": ["Files"],
+        "operationId": "getFile",
+        "summary": "Get file metadata",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/FileId"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "File metadata",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/FileResponse"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "File not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      },
+      "delete": {
+        "tags": ["Files"],
+        "operationId": "deleteFile",
+        "summary": "Delete a file",
+        "description": "Soft-deletes a file. If no other files reference the same blob, the blob is removed from MinIO.",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/FileId"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "File deleted successfully"
+          },
+          "404": {
+            "description": "File not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files/{id}/download": {
+      "get": {
+        "tags": ["Files"],
+        "operationId": "downloadFile",
+        "summary": "Download a file",
+        "description": "Downloads the file content. Supports HTTP Range header for partial content delivery.",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/FileId"
+          },
+          {
+            "name": "Range",
+            "in": "header",
+            "required": false,
+            "description": "Byte range for partial content",
+            "example": "bytes=0-1023",
+            "schema": { "type": "string" }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Full file content",
+            "content": {
+              "application/octet-stream": {
+                "schema": {
+                  "type": "string",
+                  "format": "binary"
+                }
+              }
+            }
+          },
+          "206": {
+            "description": "Partial content",
+            "content": {
+              "application/octet-stream": {
+                "schema": {
+                  "type": "string",
+                  "format": "binary"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "File not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files/folders": {
+      "post": {
+        "tags": ["Folders"],
+        "operationId": "createFolder",
+        "summary": "Create a folder",
+        "requestBody": {
+          "required": true,
+          "content": {
+            "application/json": {
+              "schema": {
+                "$ref": "#/components/schemas/CreateFolderRequest"
+              }
+            }
+          }
+        },
+        "responses": {
+          "201": {
+            "description": "Folder created",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/FolderResponse"
+                }
+              }
+            }
+          },
+          "400": {
+            "description": "Invalid request",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      },
+      "get": {
+        "tags": ["Folders"],
+        "operationId": "listFolders",
+        "summary": "List folders",
+        "parameters": [
+          {
+            "name": "parent_id",
+            "in": "query",
+            "required": false,
+            "description": "Parent folder ID (null for root)",
+            "schema": { "type": "integer", "format": "int64" }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "List of folders",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "type": "array",
+                  "items": {
+                    "$ref": "#/components/schemas/FolderResponse"
+                  }
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/files/folders/{id}": {
+      "get": {
+        "tags": ["Folders"],
+        "operationId": "getFolder",
+        "summary": "Get folder details",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/FolderId"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Folder details",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/FolderResponse"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "Folder not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      },
+      "delete": {
+        "tags": ["Folders"],
+        "operationId": "deleteFolder",
+        "summary": "Delete a folder",
+        "description": "Deletes an empty folder. Cannot delete folders that contain files or sub-folders.",
+        "parameters": [
+          {
+            "$ref": "#/components/parameters/FolderId"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Folder deleted successfully"
+          },
+          "400": {
+            "description": "Folder is not empty",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "Folder not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Internal server error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/ApiResponseError"
+                }
+              }
+            }
+          }
+        }
+      }
     }
   },
   "components": {
@@ -1143,6 +1798,46 @@
           "type": "integer",
           "format": "int64"
         }
+      },
+      "SessionId": {
+        "name": "sessionId",
+        "in": "path",
+        "required": true,
+        "description": "Upload session ID",
+        "schema": {
+          "type": "integer",
+          "format": "int64"
+        }
+      },
+      "ChunkIndex": {
+        "name": "chunkIndex",
+        "in": "path",
+        "required": true,
+        "description": "Chunk index (0-based)",
+        "schema": {
+          "type": "integer",
+          "minimum": 0
+        }
+      },
+      "FileId": {
+        "name": "id",
+        "in": "path",
+        "required": true,
+        "description": "File ID",
+        "schema": {
+          "type": "integer",
+          "format": "int64"
+        }
+      },
+      "FolderId": {
+        "name": "id",
+        "in": "path",
+        "required": true,
+        "description": "Folder ID",
+        "schema": {
+          "type": "integer",
+          "format": "int64"
+        }
       }
     },
     "schemas": {
@@ -1789,6 +2484,198 @@
             "description": "Items per page"
           }
         }
+      },
+      "InitUploadRequest": {
+        "type": "object",
+        "required": ["file_name", "file_size", "sha256", "chunk_size"],
+        "properties": {
+          "file_name": {
+            "type": "string",
+            "description": "File name"
+          },
+          "file_size": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Total file size in bytes"
+          },
+          "sha256": {
+            "type": "string",
+            "description": "SHA256 hash of the entire file (hex encoded)"
+          },
+          "chunk_size": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Chunk size in bytes (must be >= min_chunk_size config)"
+          },
+          "folder_id": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Target folder ID (null for root)",
+            "nullable": true
+          }
+        }
+      },
+      "UploadSessionResponse": {
+        "type": "object",
+        "properties": {
+          "id": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Session ID"
+          },
+          "file_name": {
+            "type": "string",
+            "description": "File name"
+          },
+          "file_size": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Total file size in bytes"
+          },
+          "chunk_size": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Chunk size in bytes"
+          },
+          "total_chunks": {
+            "type": "integer",
+            "description": "Total number of chunks"
+          },
+          "sha256": {
+            "type": "string",
+            "description": "SHA256 hash of the entire file"
+          },
+          "status": {
+            "type": "string",
+            "enum": ["pending", "uploading", "merging", "completed", "failed", "cancelled", "expired"],
+            "description": "Session status"
+          },
+          "uploaded_chunks": {
+            "type": "array",
+            "items": {
+              "type": "integer"
+            },
+            "description": "List of uploaded chunk indices"
+          },
+          "expires_at": {
+            "type": "string",
+            "format": "date-time",
+            "description": "Session expiration time"
+          }
+        }
+      },
+      "FileResponse": {
+        "type": "object",
+        "properties": {
+          "id": {
+            "type": "integer",
+            "format": "int64",
+            "description": "File ID"
+          },
+          "name": {
+            "type": "string",
+            "description": "File name"
+          },
+          "folder_id": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Parent folder ID",
+            "nullable": true
+          },
+          "size": {
+            "type": "integer",
+            "format": "int64",
+            "description": "File size in bytes"
+          },
+          "mime_type": {
+            "type": "string",
+            "description": "MIME type"
+          },
+          "sha256": {
+            "type": "string",
+            "description": "SHA256 hash"
+          },
+          "created_at": {
+            "type": "string",
+            "format": "date-time"
+          },
+          "updated_at": {
+            "type": "string",
+            "format": "date-time"
+          }
+        }
+      },
+      "FileListResponse": {
+        "type": "object",
+        "properties": {
+          "files": {
+            "type": "array",
+            "items": {
+              "$ref": "#/components/schemas/FileResponse"
+            },
+            "description": "List of files"
+          },
+          "total": {
+            "type": "integer",
+            "description": "Total number of matching files"
+          },
+          "page": {
+            "type": "integer",
+            "description": "Current page number"
+          },
+          "page_size": {
+            "type": "integer",
+            "description": "Items per page"
+          }
+        }
+      },
+      "FolderResponse": {
+        "type": "object",
+        "properties": {
+          "id": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Folder ID"
+          },
+          "name": {
+            "type": "string",
+            "description": "Folder name"
+          },
+          "parent_id": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Parent folder ID (null for root)",
+            "nullable": true
+          },
+          "path": {
+            "type": "string",
+            "description": "Materialized path (e.g. /data/reports/)"
+          },
+          "created_at": {
+            "type": "string",
+            "format": "date-time"
+          },
+          "updated_at": {
+            "type": "string",
+            "format": "date-time"
+          }
+        }
+      },
+      "CreateFolderRequest": {
+        "type": "object",
+        "required": ["name"],
+        "properties": {
+          "name": {
+            "type": "string",
+            "description": "Folder name (no path traversal characters)"
+          },
+          "parent_id": {
+            "type": "integer",
+            "format": "int64",
+            "description": "Parent folder ID (null for root)",
+            "nullable": true
+          }
+        }
       }
     }
   }