fix(handlers): bypass box creation limits for batched uploads

Update `createOrAppendBox` to accept the upload policy and admin status, allowing policy enforcement to be handled during the box creation/append decision process. This ensures that appending files to an existing batch does not incorrectly trigger daily or active box creation limits, as no new box is being created.

Also, add unit tests to verify that batched uploads successfully bypass both daily and active box creation caps.

README.md

@@ -182,7 +182,7 @@ Curl and custom uploaders can use the same endpoint:
 # Terminal-friendly output: one plain box URL.
 curl -F file=@./report.pdf http://localhost:8080/api/v1/upload
 
-# JSON output with boxUrl, manageUrl, deleteUrl, zipUrl, and file entries.
+# JSON output with boxUrl, thumbnailUrl, manageUrl, deleteUrl, zipUrl, and file entries.
 curl -F sharex=@./screenshot.png \
   -H 'Accept: application/json' \
   http://localhost:8080/api/v1/upload
@@ -190,6 +190,19 @@ curl -F sharex=@./screenshot.png \
 
 The upload endpoint accepts multipart fields named `file` and `sharex`. ShareX users can start
 from `examples/sharex/warpbox-anonymous.sxcu`; update `RequestURL` to match your instance URL.
+Authenticated uploads (your account's limits) add an `Authorization: Bearer <token>` header — mint
+a token under **Account → Access tokens**. The JSON response uses ShareX placeholders
+`{json:boxUrl}` (URL), `{json:thumbnailUrl}` (thumbnail), `{json:deleteUrl}` (deletion), and
+`{json:error}` (error message).
+
+### Grouping multiple files into one box (`X-Warpbox-Batch`)
+
+By default every uploaded file becomes its own box. To put several files in a **single** box, send
+the opt-in `X-Warpbox-Batch` header: requests that share the same header value (scoped per account,
+or per IP for anonymous uploads) within 20s are appended to the same box. This lets a multi-file
+ShareX selection — which ShareX sends as separate back-to-back requests — land as one shareable
+link. The shipped `.sxcu` sets `X-Warpbox-Batch: sharex`; remove that header for one box per file.
+Requests without the header behave exactly as before.
 
 ## Stage 4 Accounts + Personal Boxes
 

backend/libs/handlers/accounts_test.go

@@ -414,6 +414,80 @@ func TestLayeredUploadLimits(t *testing.T) {
 	}
 }
 
+func TestBatchedUploadAppendBypassesDailyBoxCreationCap(t *testing.T) {
+	app, cleanup := newTestApp(t)
+	defer cleanup()
+	policy := testPolicy(t, app)
+	policy.AnonymousDailyBoxes = 1
+	policy.AnonymousActiveBoxes = 10
+	if err := app.settingsService.UpdateUploadPolicy(policy); err != nil {
+		t.Fatalf("UpdateUploadPolicy returned error: %v", err)
+	}
+
+	first := multipartUploadRequest(t, "/api/v1/upload", "file", "first.txt", "hello")
+	first.Header.Set("Accept", "application/json")
+	first.Header.Set(uploadBatchHeader, "sharex-test")
+	firstResponse := httptest.NewRecorder()
+	app.Upload(firstResponse, first)
+	if firstResponse.Code != http.StatusCreated {
+		t.Fatalf("first batched status = %d, body = %s", firstResponse.Code, firstResponse.Body.String())
+	}
+
+	second := multipartUploadRequest(t, "/api/v1/upload", "file", "second.txt", "hello")
+	second.Header.Set("Accept", "application/json")
+	second.Header.Set(uploadBatchHeader, "sharex-test")
+	secondResponse := httptest.NewRecorder()
+	app.Upload(secondResponse, second)
+	if secondResponse.Code != http.StatusCreated {
+		t.Fatalf("second batched status = %d, body = %s", secondResponse.Code, secondResponse.Body.String())
+	}
+
+	third := multipartUploadRequest(t, "/api/v1/upload", "file", "third.txt", "hello")
+	third.Header.Set("Accept", "application/json")
+	thirdResponse := httptest.NewRecorder()
+	app.Upload(thirdResponse, third)
+	if thirdResponse.Code != http.StatusTooManyRequests {
+		t.Fatalf("non-batched status = %d, body = %s", thirdResponse.Code, thirdResponse.Body.String())
+	}
+}
+
+func TestBatchedUploadAppendBypassesActiveBoxCreationCap(t *testing.T) {
+	app, cleanup := newTestApp(t)
+	defer cleanup()
+	policy := testPolicy(t, app)
+	policy.AnonymousDailyBoxes = 10
+	policy.AnonymousActiveBoxes = 1
+	if err := app.settingsService.UpdateUploadPolicy(policy); err != nil {
+		t.Fatalf("UpdateUploadPolicy returned error: %v", err)
+	}
+
+	first := multipartUploadRequest(t, "/api/v1/upload", "file", "first.txt", "hello")
+	first.Header.Set("Accept", "application/json")
+	first.Header.Set(uploadBatchHeader, "active-cap")
+	firstResponse := httptest.NewRecorder()
+	app.Upload(firstResponse, first)
+	if firstResponse.Code != http.StatusCreated {
+		t.Fatalf("first batched status = %d, body = %s", firstResponse.Code, firstResponse.Body.String())
+	}
+
+	second := multipartUploadRequest(t, "/api/v1/upload", "file", "second.txt", "hello")
+	second.Header.Set("Accept", "application/json")
+	second.Header.Set(uploadBatchHeader, "active-cap")
+	secondResponse := httptest.NewRecorder()
+	app.Upload(secondResponse, second)
+	if secondResponse.Code != http.StatusCreated {
+		t.Fatalf("second batched status = %d, body = %s", secondResponse.Code, secondResponse.Body.String())
+	}
+
+	third := multipartUploadRequest(t, "/api/v1/upload", "file", "third.txt", "hello")
+	third.Header.Set("Accept", "application/json")
+	thirdResponse := httptest.NewRecorder()
+	app.Upload(thirdResponse, third)
+	if thirdResponse.Code != http.StatusTooManyRequests {
+		t.Fatalf("non-batched status = %d, body = %s", thirdResponse.Code, thirdResponse.Body.String())
+	}
+}
+
 func TestUserPolicyOverrideChangesUploadEnforcement(t *testing.T) {
 	app, cleanup := newTestApp(t)
 	defer cleanup()

backend/libs/handlers/admin.go

@@ -1004,10 +1004,10 @@ func (a *App) AdminUpdateUserPolicy(w http.ResponseWriter, r *http.Request) {
 		MaxUploadMB:         optionalMB(r.FormValue("max_upload_mb")),
 		DailyUploadMB:       optionalMB(r.FormValue("daily_upload_mb")),
 		StorageQuotaMB:      optionalMBAllowZero(r.FormValue("storage_quota_mb")),
-		MaxDays:             optionalInt(r.FormValue("max_days")),
+		MaxDays:             optionalIntAllowUnlimited(r.FormValue("max_days")),
-		DailyBoxes:          optionalInt(r.FormValue("daily_boxes")),
+		DailyBoxes:          optionalIntAllowUnlimited(r.FormValue("daily_boxes")),
-		ActiveBoxes:         optionalInt(r.FormValue("active_boxes")),
+		ActiveBoxes:         optionalIntAllowUnlimited(r.FormValue("active_boxes")),
-		ShortWindowRequests: optionalInt(r.FormValue("short_window_requests")),
+		ShortWindowRequests: optionalIntAllowUnlimited(r.FormValue("short_window_requests")),
 	}
 	if backendID := r.FormValue("storage_backend_id"); backendID != "" {
 		if _, err := a.uploadService.Storage().BackendConfig(backendID); err != nil {
@@ -1036,10 +1036,10 @@ func (a *App) AdminUpdateUser(w http.ResponseWriter, r *http.Request) {
 		MaxUploadMB:         optionalMB(r.FormValue("max_upload_mb")),
 		DailyUploadMB:       optionalMB(r.FormValue("daily_upload_mb")),
 		StorageQuotaMB:      optionalMBAllowZero(r.FormValue("storage_quota_mb")),
-		MaxDays:             optionalInt(r.FormValue("max_days")),
+		MaxDays:             optionalIntAllowUnlimited(r.FormValue("max_days")),
-		DailyBoxes:          optionalInt(r.FormValue("daily_boxes")),
+		DailyBoxes:          optionalIntAllowUnlimited(r.FormValue("daily_boxes")),
-		ActiveBoxes:         optionalInt(r.FormValue("active_boxes")),
+		ActiveBoxes:         optionalIntAllowUnlimited(r.FormValue("active_boxes")),
-		ShortWindowRequests: optionalInt(r.FormValue("short_window_requests")),
+		ShortWindowRequests: optionalIntAllowUnlimited(r.FormValue("short_window_requests")),
 	}
 	if backendID := r.FormValue("storage_backend_id"); backendID != "" {
 		if _, err := a.uploadService.Storage().BackendConfig(backendID); err != nil {
@@ -1206,7 +1206,7 @@ func (a *App) adminBoxes(limit int) ([]adminBoxView, error) {
 			ID:             box.ID,
 			Owner:          owner,
 			CreatedAt:      box.CreatedAt.Format("Jan 2 15:04"),
-			ExpiresAt:      box.ExpiresAt.Format("Jan 2 15:04"),
+			ExpiresAt:      boxExpiryLabel(box.ExpiresAt, "Jan 2 15:04"),
 			FileCount:      box.FileCount,
 			TotalSizeLabel: box.TotalSizeLabel,
 			DownloadCount:  box.DownloadCount,
@@ -1296,7 +1296,8 @@ func optionalMBAllowZero(value string) *float64 {
 		return nil
 	}
 	parsed, err := strconv.ParseFloat(value, 64)
-	if err != nil || parsed < 0 {
+	// 0 and -1 both mean unlimited; reject other negatives.
+	if err != nil || (parsed < 0 && parsed != -1) {
 		return nil
 	}
 	return &parsed
@@ -1313,6 +1314,18 @@ func optionalInt(value string) *int {
 	return &parsed
 }
 
+// optionalIntAllowUnlimited is like optionalInt but also accepts -1 (unlimited).
+func optionalIntAllowUnlimited(value string) *int {
+	if value == "" {
+		return nil
+	}
+	parsed, err := strconv.Atoi(value)
+	if err != nil || (parsed <= 0 && parsed != -1) {
+		return nil
+	}
+	return &parsed
+}
+
 func formatMB(value float64) string {
 	return strconv.FormatFloat(value, 'f', -1, 64) + " MB"
 }

backend/libs/handlers/api_docs.go

@@ -17,6 +17,7 @@ type apiDocsData struct {
 	ShareXExampleURL    string
 	ShareXDownloadURL   string
 	ShareXFileFieldName string
+	ShareXGroupWindow   string
 }
 
 func (a *App) APIDocs(w http.ResponseWriter, r *http.Request) {
@@ -33,6 +34,7 @@ func (a *App) APIDocs(w http.ResponseWriter, r *http.Request) {
 			ShareXExampleURL:    a.cfg.BaseURL + "/api/v1/upload",
 			ShareXDownloadURL:   a.cfg.BaseURL + "/api/v1/sharex/warpbox-anonymous.sxcu",
 			ShareXFileFieldName: "sharex",
+			ShareXGroupWindow:   uploadGroupWindow.String(),
 		},
 	})
 }
@@ -47,11 +49,16 @@ func (a *App) ShareXAnonymousConfig(w http.ResponseWriter, r *http.Request) {
 		"RequestURL":      a.cfg.BaseURL + "/api/v1/upload",
 		"Headers": map[string]string{
 			"Accept": "application/json",
+			// Group a multi-file selection (sent as back-to-back requests) into
+			// one box. Remove this header for one box per file.
+			uploadBatchHeader: "sharex",
 		},
 		"Body":         "MultipartFormData",
 		"FileFormName": "sharex",
-		"URL":          "$json:boxUrl$",
+		"URL":          "{json:boxUrl}",
-		"DeletionURL":  "$json:manageUrl$",
+		"ThumbnailURL": "{json:thumbnailUrl}",
+		"DeletionURL":  "{json:deleteUrl}",
+		"ErrorMessage": "{json:error}",
 	})
 }
 
@@ -112,8 +119,9 @@ func (a *App) UploadResponseSchema(w http.ResponseWriter, r *http.Request) {
 			"boxId":        map[string]any{"type": "string"},
 			"boxUrl":       map[string]any{"type": "string", "format": "uri"},
 			"zipUrl":       map[string]any{"type": "string", "format": "uri"},
+			"thumbnailUrl": map[string]any{"type": "string", "format": "uri", "description": "Thumbnail of the most recently uploaded file (placeholder until generated)."},
 			"manageUrl":    map[string]any{"type": "string", "format": "uri", "description": "Private bearer URL for managing/deleting this upload. Returned only at upload time."},
-			"deleteUrl": map[string]any{"type": "string", "format": "uri", "description": "Private bearer POST URL for deleting this upload. Returned only at upload time."},
+			"deleteUrl":    map[string]any{"type": "string", "format": "uri", "description": "Private bearer URL for deleting this upload (GET or POST). Returned only at upload time."},
 			"expiresAt":    map[string]any{"type": "string", "format": "date-time"},
 			"files": map[string]any{
 				"type": "array",
@@ -125,6 +133,7 @@ func (a *App) UploadResponseSchema(w http.ResponseWriter, r *http.Request) {
 						"name":         map[string]any{"type": "string"},
 						"size":         map[string]any{"type": "string"},
 						"url":          map[string]any{"type": "string", "format": "uri"},
+						"thumbnailUrl": map[string]any{"type": "string", "format": "uri"},
 					},
 				},
 			},

backend/libs/handlers/app.go

@@ -18,6 +18,7 @@ type App struct {
 	settingsService *services.SettingsService
 	banService      *services.BanService
 	rateLimiter     *rateLimiter
+	uploadGroups    *uploadGrouper
 }
 
 func NewApp(cfg config.Config, logger *slog.Logger, renderer *web.Renderer, uploadService *services.UploadService, authService *services.AuthService, settingsService *services.SettingsService, banService *services.BanService) *App {
@@ -30,6 +31,7 @@ func NewApp(cfg config.Config, logger *slog.Logger, renderer *web.Renderer, uplo
 		settingsService: settingsService,
 		banService:      banService,
 		rateLimiter:     newRateLimiter(),
+		uploadGroups:    newUploadGrouper(),
 	}
 }
 
@@ -112,6 +114,9 @@ func (a *App) RegisterRoutes(mux *http.ServeMux) {
 	mux.HandleFunc("GET /d/{boxID}/deleted", a.ManageDeleted)
 	mux.HandleFunc("GET /d/{boxID}/manage/{token}", a.ManageBox)
 	mux.HandleFunc("POST /d/{boxID}/manage/{token}/delete", a.ManageDeleteBox)
+	// GET variant so ShareX (which issues a GET to the configured DeletionURL)
+	// can delete a box via its secret one-time delete token.
+	mux.HandleFunc("GET /d/{boxID}/manage/{token}/delete", a.ManageDeleteBox)
 	mux.HandleFunc("POST /d/{boxID}/unlock", a.UnlockBox)
 	mux.HandleFunc("GET /d/{boxID}/zip", a.DownloadZip)
 	mux.HandleFunc("GET /d/{boxID}/f/{fileID}", a.DownloadFile)

backend/libs/handlers/dashboard.go

@@ -82,7 +82,7 @@ func (a *App) Dashboard(w http.ResponseWriter, r *http.Request) {
 			FileCount:      len(row.Box.Files),
 			Size:           row.TotalSizeLabel,
 			CreatedAt:      row.Box.CreatedAt.Format("Jan 2 15:04"),
-			ExpiresAt:      row.Box.ExpiresAt.Format("Jan 2 15:04"),
+			ExpiresAt:      boxExpiryLabel(row.Box.ExpiresAt, "Jan 2 15:04"),
 			URL:            "/d/" + row.Box.ID,
 		})
 	}

backend/libs/handlers/download.go

@@ -78,7 +78,7 @@ func (a *App) DownloadPage(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	expiresLabel := box.ExpiresAt.Format("Jan 2, 2006 15:04 MST")
+	expiresLabel := boxExpiryLabel(box.ExpiresAt, "Jan 2, 2006 15:04 MST")
 	title := "Shared files on Warpbox"
 	description := fmt.Sprintf("%d file%s shared via Warpbox · expires %s", len(box.Files), plural(len(box.Files)), expiresLabel)
 	if locked && box.Obfuscate {
@@ -337,6 +337,21 @@ func unlockCookieName(boxID string) string {
 	return "warpbox_unlock_" + strings.NewReplacer("-", "_", ".", "_").Replace(boxID)
 }
 
+// neverExpires reports whether a box's expiry is far enough out to be treated as
+// "forever" (set via the unlimited / -1 expiry option).
+func neverExpires(t time.Time) bool {
+	return time.Until(t) > 50*365*24*time.Hour
+}
+
+// boxExpiryLabel formats a box's expiry with the given layout, rendering
+// "forever" boxes as "Never" instead of a meaningless far-future date.
+func boxExpiryLabel(t time.Time, layout string) string {
+	if neverExpires(t) {
+		return "Never"
+	}
+	return t.Format(layout)
+}
+
 func absoluteURL(r *http.Request, path string) string {
 	if strings.HasPrefix(path, "http://") || strings.HasPrefix(path, "https://") {
 		return path

backend/libs/handlers/manage.go

@@ -82,7 +82,7 @@ func (a *App) managePageData(box services.Box, token string) managePageData {
 		Token:           token,
 		FileCount:       len(box.Files),
 		TotalSize:       helpers.FormatBytes(totalSize),
-		ExpiresLabel:    box.ExpiresAt.Format("Jan 2, 2006 15:04 MST"),
+		ExpiresLabel:    boxExpiryLabel(box.ExpiresAt, "Jan 2, 2006 15:04 MST"),
 		DownloadCount:   box.DownloadCount,
 		MaxDownloads:    box.MaxDownloads,
 		Protected:       a.uploadService.IsProtected(box),

backend/libs/handlers/pages.go

@@ -75,6 +75,10 @@ func (a *App) homeExpiryOptions(settings services.UploadPolicySettings, user ser
 		unlimited = true
 	case loggedIn:
 		maxDays = a.settingsService.EffectivePolicyForUser(settings, user).MaxDays
+		// A negative per-user MaxDays override means unlimited retention.
+		if maxDays < 0 {
+			unlimited = true
+		}
 	}
 	return buildExpiryOptions(maxDays, unlimited)
 }
@@ -103,6 +107,10 @@ func buildExpiryOptions(maxDays int, unlimited bool) ([]expiryOption, int) {
 	if len(options) == 0 {
 		options = append(options, expiryOption{Minutes: capMinutes, Label: expiryLabel(capMinutes)})
 	}
+	// Unlimited uploaders can pick "never expires" (sentinel -1) after the ladder.
+	if unlimited {
+		options = append(options, expiryOption{Minutes: -1, Label: "Unlimited (never expires)"})
+	}
 
 	// Default to 24h when available, otherwise the smallest option offered.
 	defaultMinutes := options[0].Minutes
@@ -154,5 +162,9 @@ func (a *App) homeUploadPolicyLabels(settings services.UploadPolicySettings, use
 	if policy.StorageQuotaSet {
 		quota = services.FormatMegabytesLabel(policy.StorageQuotaMB)
 	}
-	return maxUpload, "Daily cap: " + services.FormatMegabytesLabel(policy.DailyUploadMB) + " · Storage quota: " + quota + " · " + strconv.Itoa(policy.MaxDays) + " day max."
+	expiryLimit := strconv.Itoa(policy.MaxDays) + " day max."
+	if policy.MaxDays < 0 {
+		expiryLimit = "no expiry limit."
+	}
+	return maxUpload, "Daily cap: " + services.FormatMegabytesLabel(policy.DailyUploadMB) + " · Storage quota: " + quota + " · " + expiryLimit
 }

backend/libs/handlers/upload.go

@@ -36,7 +36,7 @@ func (a *App) Upload(w http.ResponseWriter, r *http.Request) {
 	}
 	effectivePolicy := a.effectiveUploadPolicy(settings, user, loggedIn)
 	rateKey := uploadRateKey(r, user, loggedIn)
-	if !isAdminUpload && !a.rateLimiter.Allow("upload:"+rateKey, effectivePolicy.ShortRequests, effectivePolicy.ShortWindow, time.Now().UTC()) {
+	if !isAdminUpload && effectivePolicy.ShortRequests > 0 && !a.rateLimiter.Allow("upload:"+rateKey, effectivePolicy.ShortRequests, effectivePolicy.ShortWindow, time.Now().UTC()) {
 		a.logger.Warn("upload rate limited", "source", "user-upload", "severity", "warn", "code", 4290, "ip", uploadClientIP(r), "user_id", user.ID)
 		helpers.WriteJSONError(w, http.StatusTooManyRequests, "too many upload requests, please slow down")
 		return
@@ -77,22 +77,39 @@ func (a *App) Upload(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 	}
-	maxDays := parseInt(r.FormValue("max_days"))
+	// Unlimited expiry: admins, or users whose effective MaxDays is negative.
+	unlimitedExpiry := isAdminUpload || effectivePolicy.MaxDays < 0
+
+	rawMaxDays := parseInt(r.FormValue("max_days"))
+	maxDays := rawMaxDays
 	if maxDays <= 0 {
-		maxDays = min(7, effectivePolicy.MaxDays)
+		maxDays = 7
+		if effectivePolicy.MaxDays > 0 && effectivePolicy.MaxDays < maxDays {
+			maxDays = effectivePolicy.MaxDays
 		}
-	if !isAdminUpload && maxDays > effectivePolicy.MaxDays {
+	}
+	if !unlimitedExpiry && maxDays > effectivePolicy.MaxDays {
 		a.logger.Warn("upload rejected expiration days", "source", "user-upload", "severity", "warn", "code", 4131, "ip", uploadClientIP(r), "user_id", user.ID, "requested_days", maxDays, "max_days", effectivePolicy.MaxDays)
 		helpers.WriteJSONError(w, http.StatusRequestEntityTooLarge, fmt.Sprintf("expiration cannot exceed %d days", effectivePolicy.MaxDays))
 		return
 	}
+
 	expiresMinutes := parseInt(r.FormValue("expires_minutes"))
-	if expiresMinutes > 0 && !isAdminUpload && expiresMinutes > effectivePolicy.MaxDays*24*60 {
+	// A negative expires_minutes (or max_days) is the "never expires" request.
+	// Only honour it for unlimited uploaders; otherwise it's an invalid value.
+	if expiresMinutes < 0 || rawMaxDays < 0 {
+		if !unlimitedExpiry {
+			a.logger.Warn("upload rejected unlimited expiration", "source", "user-upload", "severity", "warn", "code", 4133, "ip", uploadClientIP(r), "user_id", user.ID)
+			helpers.WriteJSONError(w, http.StatusRequestEntityTooLarge, fmt.Sprintf("expiration cannot exceed %d days", effectivePolicy.MaxDays))
+			return
+		}
+		expiresMinutes = -1
+	} else if expiresMinutes > 0 && !unlimitedExpiry && expiresMinutes > effectivePolicy.MaxDays*24*60 {
 		a.logger.Warn("upload rejected expiration minutes", "source", "user-upload", "severity", "warn", "code", 4132, "ip", uploadClientIP(r), "user_id", user.ID, "requested_minutes", expiresMinutes, "max_days", effectivePolicy.MaxDays)
 		helpers.WriteJSONError(w, http.StatusRequestEntityTooLarge, fmt.Sprintf("expiration cannot exceed %d days", effectivePolicy.MaxDays))
 		return
 	}
-	result, err := a.uploadService.CreateBox(files, services.UploadOptions{
+	opts := services.UploadOptions{
 		MaxDays:           maxDays,
 		ExpiresInMinutes:  expiresMinutes,
 		MaxDownloads:      parseInt(r.FormValue("max_downloads")),
@@ -103,14 +120,20 @@ func (a *App) Upload(w http.ResponseWriter, r *http.Request) {
 		SkipSizeLimit:     isAdminUpload || effectivePolicy.MaxUploadMB < 0,
 		CreatorIP:         uploadClientIP(r),
 		StorageBackendID:  effectivePolicy.StorageBackendID,
-	})
+	}
+	result, boxesAdded, status, policyMessage, err := a.createOrAppendBox(r, user, loggedIn, effectivePolicy, files, opts, !isAdminUpload)
+	if policyMessage != "" {
+		a.logger.Warn("upload rejected by policy", "source", "quota", "severity", "warn", "code", status, "ip", uploadClientIP(r), "user_id", user.ID, "message", policyMessage, "bytes", totalBytes, "files", len(files))
+		helpers.WriteJSONError(w, status, policyMessage)
+		return
+	}
 	if err != nil {
 		a.logger.Warn("upload failed", "source", "user-upload", "severity", "warn", "code", 4001, "ip", uploadClientIP(r), "user_id", user.ID, "error", err.Error())
 		helpers.WriteJSONError(w, http.StatusBadRequest, err.Error())
 		return
 	}
 	if !isAdminUpload {
-		if err := a.recordUploadUsage(r, user, loggedIn, totalBytes, 1); err != nil {
+		if err := a.recordUploadUsage(r, user, loggedIn, totalBytes, boxesAdded); err != nil {
 			a.logger.Warn("failed to record upload usage", "source", "quota", "severity", "warn", "code", 4402, "error", err.Error())
 		}
 		if err := a.settingsService.CleanupUsage(time.Now().UTC(), settings.UsageRetentionDays); err != nil {
@@ -130,6 +153,77 @@ func (a *App) Upload(w http.ResponseWriter, r *http.Request) {
 	_, _ = fmt.Fprintln(w, result.BoxURL)
 }
 
+// createOrAppendBox creates a new box. It only ever appends to an existing box
+// when the request opts in via the X-Warpbox-Batch header: requests sharing the
+// same batch value (per account, or per IP for anonymous) within
+// uploadGroupWindow are folded into one box. Without the header the behaviour is
+// identical to creating a fresh box every time. Returns the result and how many
+// boxes were created (1 for a new box, 0 for an append) for usage accounting.
+func (a *App) createOrAppendBox(r *http.Request, user services.User, loggedIn bool, policy services.EffectiveUploadPolicy, files []*multipart.FileHeader, opts services.UploadOptions, enforceBoxLimits bool) (services.UploadResult, int, int, string, error) {
+	batch := strings.TrimSpace(r.Header.Get(uploadBatchHeader))
+	if batch == "" {
+		if enforceBoxLimits {
+			if status, message := a.checkBoxCreationPolicy(r, user, loggedIn, policy); message != "" {
+				return services.UploadResult{}, 0, status, message, nil
+			}
+		}
+		result, err := a.uploadService.CreateBox(files, opts)
+		if err != nil {
+			return services.UploadResult{}, 0, 0, "", err
+		}
+		return result, 1, 0, "", nil
+	}
+
+	// Group key is scoped to the uploader so batches never cross accounts/IPs.
+	identity := "ip:" + uploadClientIP(r)
+	if loggedIn {
+		identity = "user:" + user.ID
+	}
+	entry := a.uploadGroups.entryFor(identity + "|" + batch)
+
+	// Hold the per-key lock across the whole create/append so concurrent batched
+	// uploads serialise into the same box instead of racing.
+	entry.mu.Lock()
+	defer entry.mu.Unlock()
+
+	if entry.boxID != "" && time.Since(entry.at) < uploadGroupWindow {
+		if box, err := a.uploadService.GetBox(entry.boxID); err == nil && a.batchBoxMatches(box, user, loggedIn, r) && a.uploadService.CanDownload(box) == nil {
+			if result, err := a.uploadService.AppendFiles(entry.boxID, files, opts); err == nil {
+				// Re-attach the manage/delete URLs from the box's creation so every
+				// upload in the batch returns a working deletion URL.
+				result.ManageURL = entry.manageURL
+				result.DeleteURL = entry.deleteURL
+				entry.at = time.Now()
+				return result, 0, 0, "", nil
+			}
+		}
+	}
+
+	if enforceBoxLimits {
+		if status, message := a.checkBoxCreationPolicy(r, user, loggedIn, policy); message != "" {
+			return services.UploadResult{}, 0, status, message, nil
+		}
+	}
+	result, err := a.uploadService.CreateBox(files, opts)
+	if err != nil {
+		return services.UploadResult{}, 0, 0, "", err
+	}
+	entry.boxID = result.BoxID
+	entry.manageURL = result.ManageURL
+	entry.deleteURL = result.DeleteURL
+	entry.at = time.Now()
+	return result, 1, 0, "", nil
+}
+
+// batchBoxMatches guards that a batched append only ever touches a box owned by
+// the same uploader (account for logged-in users, creator IP for anonymous).
+func (a *App) batchBoxMatches(box services.Box, user services.User, loggedIn bool, r *http.Request) bool {
+	if loggedIn {
+		return box.OwnerID == user.ID
+	}
+	return box.OwnerID == "" && box.CreatorIP == uploadClientIP(r)
+}
+
 func (a *App) checkUploadPolicy(r *http.Request, user services.User, loggedIn bool, settings services.UploadPolicySettings, policy services.EffectiveUploadPolicy, files []*multipart.FileHeader, totalBytes int64) (int, string) {
 	if len(files) == 0 {
 		return 0, ""
@@ -151,16 +245,6 @@ func (a *App) checkUploadPolicy(r *http.Request, user services.User, loggedIn bo
 		if policy.DailyUploadMB > 0 && usage.UploadedBytes+totalBytes > services.MegabytesToBytes(policy.DailyUploadMB) {
 			return http.StatusTooManyRequests, "anonymous daily upload limit reached"
 		}
-		if usage.UploadedBoxes+1 > policy.DailyBoxes {
-			return http.StatusTooManyRequests, "anonymous daily box limit reached"
-		}
-		activeBoxes, err := a.uploadService.ActiveBoxCountForIP(uploadClientIP(r))
-		if err != nil {
-			return http.StatusInternalServerError, "active box limit could not be checked"
-		}
-		if activeBoxes+1 > policy.ActiveBoxes {
-			return http.StatusTooManyRequests, "anonymous active box limit reached"
-		}
 		if status, message := a.checkStorageBackendCapacity(policy.StorageBackendID, settings, totalBytes); message != "" {
 			return status, message
 		}
@@ -174,16 +258,6 @@ func (a *App) checkUploadPolicy(r *http.Request, user services.User, loggedIn bo
 	if policy.DailyUploadMB > 0 && usage.UploadedBytes+totalBytes > services.MegabytesToBytes(policy.DailyUploadMB) {
 		return http.StatusTooManyRequests, "daily upload limit reached"
 	}
-	if usage.UploadedBoxes+1 > policy.DailyBoxes {
-		return http.StatusTooManyRequests, "daily box limit reached"
-	}
-	activeBoxes, err := a.uploadService.ActiveBoxCountForUser(user.ID)
-	if err != nil {
-		return http.StatusInternalServerError, "active box limit could not be checked"
-	}
-	if activeBoxes+1 > policy.ActiveBoxes {
-		return http.StatusTooManyRequests, "active box limit reached"
-	}
 	activeStorage, err := a.uploadService.UserActiveStorageUsed(user.ID)
 	if err != nil {
 		return http.StatusInternalServerError, "storage quota could not be checked"
@@ -197,6 +271,42 @@ func (a *App) checkUploadPolicy(r *http.Request, user services.User, loggedIn bo
 	return 0, ""
 }
 
+func (a *App) checkBoxCreationPolicy(r *http.Request, user services.User, loggedIn bool, policy services.EffectiveUploadPolicy) (int, string) {
+	now := time.Now().UTC()
+	if !loggedIn {
+		usage, err := a.settingsService.UsageForIP(uploadClientIP(r), now)
+		if err != nil {
+			return http.StatusInternalServerError, "upload usage could not be checked"
+		}
+		if policy.DailyBoxes > 0 && usage.UploadedBoxes+1 > policy.DailyBoxes {
+			return http.StatusTooManyRequests, "anonymous daily box limit reached"
+		}
+		activeBoxes, err := a.uploadService.ActiveBoxCountForIP(uploadClientIP(r))
+		if err != nil {
+			return http.StatusInternalServerError, "active box limit could not be checked"
+		}
+		if policy.ActiveBoxes > 0 && activeBoxes+1 > policy.ActiveBoxes {
+			return http.StatusTooManyRequests, "anonymous active box limit reached"
+		}
+		return 0, ""
+	}
+	usage, err := a.settingsService.UsageForUser(user.ID, now)
+	if err != nil {
+		return http.StatusInternalServerError, "upload usage could not be checked"
+	}
+	if policy.DailyBoxes > 0 && usage.UploadedBoxes+1 > policy.DailyBoxes {
+		return http.StatusTooManyRequests, "daily box limit reached"
+	}
+	activeBoxes, err := a.uploadService.ActiveBoxCountForUser(user.ID)
+	if err != nil {
+		return http.StatusInternalServerError, "active box limit could not be checked"
+	}
+	if policy.ActiveBoxes > 0 && activeBoxes+1 > policy.ActiveBoxes {
+		return http.StatusTooManyRequests, "active box limit reached"
+	}
+	return 0, ""
+}
+
 func (a *App) recordUploadUsage(r *http.Request, user services.User, loggedIn bool, totalBytes int64, boxes int) error {
 	now := time.Now().UTC()
 	if loggedIn {

backend/libs/handlers/upload_group.go

@@ -0,0 +1,76 @@
+package handlers
+
+import (
+	"sync"
+	"time"
+)
+
+// uploadGroupWindow is how long after a batched upload a follow-up upload with
+// the same X-Warpbox-Batch value (and same account/IP) is folded into the same
+// box. ShareX sends a multi-file selection as separate back-to-back requests;
+// the batch header lets it land them in one box.
+const uploadGroupWindow = 20 * time.Second
+
+// uploadBatchHeader is the opt-in request header. Without it, uploads behave
+// exactly as before (one box per request). With it, requests sharing the same
+// value (per account/IP) within uploadGroupWindow are grouped into one box.
+const uploadBatchHeader = "X-Warpbox-Batch"
+
+// uploadGroupPruneInterval is how often entryFor drops stale entries so the map
+// can't grow without bound (one key per account/IP + batch value otherwise).
+const uploadGroupPruneInterval = 5 * time.Minute
+
+// uploadGrouper tracks the most recent box per batch key so opt-in batched
+// uploads land in a single box. Each key has its own lock, which also serialises
+// that key's concurrent uploads so they append to the same box instead of racing
+// to create several.
+type uploadGrouper struct {
+	mu        sync.Mutex
+	entries   map[string]*uploadGroupEntry
+	lastPrune time.Time
+}
+
+type uploadGroupEntry struct {
+	mu        sync.Mutex
+	boxID     string
+	manageURL string
+	deleteURL string
+	at        time.Time
+}
+
+func newUploadGrouper() *uploadGrouper {
+	return &uploadGrouper{entries: make(map[string]*uploadGroupEntry)}
+}
+
+func (g *uploadGrouper) entryFor(key string) *uploadGroupEntry {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+	g.pruneLocked(time.Now())
+	entry, ok := g.entries[key]
+	if !ok {
+		entry = &uploadGroupEntry{at: time.Now()}
+		g.entries[key] = entry
+	}
+	return entry
+}
+
+// pruneLocked drops entries whose last use is well past the grouping window so
+// the map stays bounded to recently-active keys. Callers must hold g.mu. Entries
+// currently in use are kept to avoid removing one a request is about to
+// populate.
+func (g *uploadGrouper) pruneLocked(now time.Time) {
+	if now.Sub(g.lastPrune) < uploadGroupPruneInterval {
+		return
+	}
+	g.lastPrune = now
+	for key, entry := range g.entries {
+		if !entry.mu.TryLock() {
+			continue
+		}
+		stale := now.Sub(entry.at) > 2*uploadGroupWindow
+		entry.mu.Unlock()
+		if stale {
+			delete(g.entries, key)
+		}
+	}
+}

backend/libs/handlers/upload_group_test.go

@@ -0,0 +1,24 @@
+package handlers
+
+import (
+	"testing"
+	"time"
+)
+
+func TestUploadGroupPrunesFailedEntries(t *testing.T) {
+	g := newUploadGrouper()
+	entry := g.entryFor("ip:203.0.113.1|failed")
+	entry.mu.Lock()
+	entry.at = time.Now().Add(-3 * uploadGroupWindow)
+	entry.mu.Unlock()
+	g.lastPrune = time.Now().Add(-uploadGroupPruneInterval)
+
+	_ = g.entryFor("ip:203.0.113.1|next")
+
+	if _, ok := g.entries["ip:203.0.113.1|failed"]; ok {
+		t.Fatalf("stale failed entry was not pruned")
+	}
+	if _, ok := g.entries["ip:203.0.113.1|next"]; !ok {
+		t.Fatalf("new entry was not created")
+	}
+}

backend/libs/middleware/bans.go

@@ -26,10 +26,20 @@ func Bans(logger *slog.Logger, bans *services.BanService, trustedProxies []strin
 					return
 				}
 
+				settings, err := bans.Settings()
+				if err != nil {
+					logger.Error("ban settings load failed", "source", "ban", "severity", "error", "code", 5004, "ip", ip, "error", err.Error())
+					next.ServeHTTP(w, r)
+					return
+				}
+				if !settings.AutoBanEnabled {
+					next.ServeHTTP(w, r)
+					return
+				}
 				if pattern, err := bans.MaliciousPattern(r.URL.Path); err != nil {
 					logger.Error("malicious path check failed", "source", "ban", "severity", "error", "code", 5002, "ip", ip, "error", err.Error())
 				} else if pattern != "" {
-					if result, err := bans.RecordAbuse(ip, services.AbuseKindMaliciousPath, r.URL.Path, banThreshold(bans, services.AbuseKindMaliciousPath), now); err != nil {
+					if result, err := bans.RecordAbuse(ip, services.AbuseKindMaliciousPath, r.URL.Path, settings.MaliciousPathThreshold, now); err != nil {
 						logger.Error("malicious path event failed", "source", "ban", "severity", "error", "code", 5003, "ip", ip, "path", r.URL.Path, "error", err.Error())
 					} else if result.Enabled {
 						logger.Warn("malicious path requested", "source", "ban", "severity", "warn", "code", 4302, "ip", ip, "path", r.URL.Path, "pattern", pattern, "count", result.Event.Count)
@@ -48,18 +58,3 @@ func Bans(logger *slog.Logger, bans *services.BanService, trustedProxies []strin
 		})
 	}
 }
-
-func banThreshold(bans *services.BanService, kind string) int {
-	settings, err := bans.Settings()
-	if err != nil {
-		return 0
-	}
-	switch kind {
-	case services.AbuseKindAdminLogin:
-		return settings.AdminLoginFailureThreshold
-	case services.AbuseKindUserLogin:
-		return settings.UserLoginFailureThreshold
-	default:
-		return settings.MaliciousPathThreshold
-	}
-}

backend/libs/middleware/bans_test.go

@@ -79,6 +79,26 @@ func TestBansMiddlewareAutoBansMaliciousPaths(t *testing.T) {
 	}
 }
 
+func TestBansMiddlewareSkipsAutoBanWhenDisabled(t *testing.T) {
+	bans := newMiddlewareBanService(t)
+	handler := Chain(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.NotFound(w, r)
+	}), Bans(slog.New(slog.NewTextHandler(io.Discard, nil)), bans, nil))
+
+	for i := 0; i < 5; i++ {
+		request := httptest.NewRequest(http.MethodGet, "/.env", nil)
+		request.RemoteAddr = "203.0.113.23:6070"
+		response := httptest.NewRecorder()
+		handler.ServeHTTP(response, request)
+		if response.Code == http.StatusForbidden {
+			t.Fatalf("request %d was blocked while auto-ban disabled", i+1)
+		}
+	}
+	if _, ok, err := bans.Match("203.0.113.23", time.Now().UTC()); err != nil || ok {
+		t.Fatalf("disabled auto-ban Match = %v, %v", ok, err)
+	}
+}
+
 func newMiddlewareBanService(t *testing.T) *services.BanService {
 	t.Helper()
 	root := t.TempDir()

backend/libs/services/auth.go

@@ -862,20 +862,20 @@ func validateUserPolicy(policy UserPolicy) error {
 	if policy.DailyUploadMB != nil && ((*policy.DailyUploadMB < 0 && *policy.DailyUploadMB != -1) || *policy.DailyUploadMB == 0) {
 		return fmt.Errorf("daily upload override must be positive or -1 for unlimited")
 	}
-	if policy.StorageQuotaMB != nil && *policy.StorageQuotaMB < 0 {
+	if policy.StorageQuotaMB != nil && *policy.StorageQuotaMB < 0 && *policy.StorageQuotaMB != -1 {
-		return fmt.Errorf("storage quota override cannot be negative")
+		return fmt.Errorf("storage quota override must be 0/positive or -1 for unlimited")
 	}
-	if policy.MaxDays != nil && *policy.MaxDays <= 0 {
+	if policy.MaxDays != nil && *policy.MaxDays <= 0 && *policy.MaxDays != -1 {
-		return fmt.Errorf("expiration override must be positive")
+		return fmt.Errorf("expiration override must be positive or -1 for unlimited")
 	}
-	if policy.DailyBoxes != nil && *policy.DailyBoxes <= 0 {
+	if policy.DailyBoxes != nil && *policy.DailyBoxes <= 0 && *policy.DailyBoxes != -1 {
-		return fmt.Errorf("daily box override must be positive")
+		return fmt.Errorf("daily box override must be positive or -1 for unlimited")
 	}
-	if policy.ActiveBoxes != nil && *policy.ActiveBoxes <= 0 {
+	if policy.ActiveBoxes != nil && *policy.ActiveBoxes <= 0 && *policy.ActiveBoxes != -1 {
-		return fmt.Errorf("active box override must be positive")
+		return fmt.Errorf("active box override must be positive or -1 for unlimited")
 	}
-	if policy.ShortWindowRequests != nil && *policy.ShortWindowRequests <= 0 {
+	if policy.ShortWindowRequests != nil && *policy.ShortWindowRequests <= 0 && *policy.ShortWindowRequests != -1 {
-		return fmt.Errorf("short-window request override must be positive")
+		return fmt.Errorf("short-window request override must be positive or -1 for unlimited")
 	}
 	return nil
 }

backend/libs/services/bans.go

@@ -312,7 +312,11 @@ func (s *BanService) Match(ip string, now time.Time) (MatchedBan, bool, error) {
 	}
 	now = now.UTC()
 	var matched BanRecord
-	err := s.db.Update(func(tx *bbolt.Tx) error {
+	var matchedKey []byte
+	// Read-only scan first: the common case (no match) only takes a concurrent
+	// read transaction, instead of grabbing the single bbolt write lock on every
+	// request that flows through the ban middleware.
+	err := s.db.View(func(tx *bbolt.Tx) error {
 		bucket := tx.Bucket(bansBucket)
 		return bucket.ForEach(func(key, value []byte) error {
 			if matched.ID != "" {
@@ -325,20 +329,37 @@ func (s *BanService) Match(ip string, now time.Time) (MatchedBan, bool, error) {
 			if !record.Active(now) || !banTargetMatches(record.Normalized, parsed) {
 				return nil
 			}
+			matched = record
+			matchedKey = append([]byte(nil), key...) // key bytes are only valid within the txn
+			return nil
+		})
+	})
+	if err != nil || matched.ID == "" {
+		return MatchedBan{Ban: matched, IP: ip}, matched.ID != "", err
+	}
+
+	// On a hit, record the match time in a short write transaction.
+	matched.LastMatchedAt = &now
+	matched.UpdatedAt = now
+	_ = s.db.Update(func(tx *bbolt.Tx) error {
+		bucket := tx.Bucket(bansBucket)
+		data := bucket.Get(matchedKey)
+		if data == nil {
+			return nil
+		}
+		var record BanRecord
+		if err := json.Unmarshal(data, &record); err != nil {
+			return nil
+		}
 		record.LastMatchedAt = &now
 		record.UpdatedAt = now
 		next, err := json.Marshal(record)
 		if err != nil {
-				return err
-			}
-			if err := bucket.Put(key, next); err != nil {
-				return err
-			}
-			matched = record
 			return nil
+		}
+		return bucket.Put(matchedKey, next)
 	})
-	})
+	return MatchedBan{Ban: matched, IP: ip}, true, nil
-	return MatchedBan{Ban: matched, IP: ip}, matched.ID != "", err
 }
 
 func (r BanRecord) Active(now time.Time) bool {
@@ -498,6 +519,11 @@ func (s *BanService) RecordAbuse(ip, kind, detail string, threshold int, now tim
 	if err != nil || !triggered {
 		return AbuseResult{Event: event, Triggered: false, Enabled: true}, err
 	}
+	if matched, ok, err := s.Match(ip, now); err != nil {
+		return AbuseResult{}, err
+	} else if ok {
+		return AbuseResult{Event: event, Ban: matched.Ban, Triggered: true, Enabled: true}, nil
+	}
 	reason := fmt.Sprintf("%s threshold reached: %s", strings.ReplaceAll(kind, "_", " "), detail)
 	ban, err = s.createBan(ip, reason, BanSourceAuto, "", now.Add(time.Duration(settings.AutoBanDurationHours)*time.Hour), now)
 	if err != nil {

backend/libs/services/bans_test.go

@@ -79,6 +79,17 @@ func TestBanServiceAutoBanThresholdsAndDisabled(t *testing.T) {
 	if err != nil || !result.Triggered || result.Ban.ID == "" {
 		t.Fatalf("RecordAbuse threshold = %+v, %v", result, err)
 	}
+	again, err := bans.RecordAbuse("203.0.113.8", AbuseKindMaliciousPath, "/.env", 3, now.Add(4*time.Minute))
+	if err != nil || !again.Triggered || again.Ban.ID != result.Ban.ID {
+		t.Fatalf("RecordAbuse duplicate = %+v, %v", again, err)
+	}
+	records, err := bans.ListBans()
+	if err != nil {
+		t.Fatalf("ListBans returned error: %v", err)
+	}
+	if len(records) != 1 {
+		t.Fatalf("ban count = %d, want 1", len(records))
+	}
 }
 
 func TestBanServiceMaliciousPathRules(t *testing.T) {

backend/libs/services/upload.go

@@ -85,6 +85,7 @@ type UploadResult struct {
 	BoxID        string       `json:"boxId"`
 	BoxURL       string       `json:"boxUrl"`
 	ZipURL       string       `json:"zipUrl"`
+	ThumbnailURL string       `json:"thumbnailUrl"`
 	ManageURL    string       `json:"manageUrl"`
 	DeleteURL    string       `json:"deleteUrl"`
 	ExpiresAt    string       `json:"expiresAt"`
@@ -96,6 +97,7 @@ type ResultFile struct {
 	Name         string `json:"name"`
 	Size         string `json:"size"`
 	URL          string `json:"url"`
+	ThumbnailURL string `json:"thumbnailUrl"`
 }
 
 type AdminStats struct {
@@ -196,14 +198,21 @@ func (s *UploadService) CreateBox(files []*multipart.FileHeader, opts UploadOpti
 	if len(files) == 0 {
 		return UploadResult{}, fmt.Errorf("no files were uploaded")
 	}
-	if opts.MaxDays <= 0 {
-		opts.MaxDays = 7
-	}
-
 	now := time.Now().UTC()
-	expiresAt := now.Add(time.Duration(opts.MaxDays) * 24 * time.Hour)
+	var expiresAt time.Time
-	if opts.ExpiresInMinutes > 0 {
+	switch {
+	case opts.ExpiresInMinutes < 0 || opts.MaxDays < 0:
+		// "Forever" — a date far enough out that the box effectively never
+		// expires. No schema change; CanDownload/cleanup keep working as-is.
+		expiresAt = now.AddDate(100, 0, 0)
+	case opts.ExpiresInMinutes > 0:
 		expiresAt = now.Add(time.Duration(opts.ExpiresInMinutes) * time.Minute)
+	default:
+		days := opts.MaxDays
+		if days <= 0 {
+			days = 7
+		}
+		expiresAt = now.Add(time.Duration(days) * 24 * time.Hour)
 	}
 
 	box := Box{
@@ -226,15 +235,66 @@ func (s *UploadService) CreateBox(files []*multipart.FileHeader, opts UploadOpti
 		box.PasswordHash = hash
 	}
 
-	backend, err := s.storage.Backend(box.StorageBackendID)
+	if err := s.writeFilesToBox(&box, files, opts); err != nil {
+		return UploadResult{}, err
+	}
+
+	if err := s.SaveBox(box); err != nil {
+		return UploadResult{}, err
+	}
+
+	s.logger.Info("upload complete",
+		"source", "user-upload",
+		"severity", "user_activity",
+		"code", 2001,
+		"box_id", box.ID,
+		"file_count", len(box.Files),
+	)
+
+	return s.resultForBox(box, deleteToken), nil
+}
+
+// AppendFiles adds files to an existing box (used to group a ShareX multi-file
+// selection into a single box). The box keeps its original expiry, password and
+// other settings; only the new files are written.
+func (s *UploadService) AppendFiles(boxID string, files []*multipart.FileHeader, opts UploadOptions) (UploadResult, error) {
+	if len(files) == 0 {
+		return UploadResult{}, fmt.Errorf("no files were uploaded")
+	}
+	box, err := s.GetBox(boxID)
 	if err != nil {
 		return UploadResult{}, err
 	}
+	if err := s.writeFilesToBox(&box, files, opts); err != nil {
+		return UploadResult{}, err
+	}
+	if err := s.SaveBox(box); err != nil {
+		return UploadResult{}, err
+	}
+	s.logger.Info("upload appended",
+		"source", "user-upload",
+		"severity", "user_activity",
+		"code", 2001,
+		"box_id", box.ID,
+		"added", len(files),
+		"file_count", len(box.Files),
+	)
+	return s.resultForBox(box, ""), nil
+}
+
+// writeFilesToBox streams each uploaded file into the box's storage backend and
+// appends the file metadata to box.Files. The box's StorageBackendID determines
+// where files land, so it works for both new and existing boxes.
+func (s *UploadService) writeFilesToBox(box *Box, files []*multipart.FileHeader, opts UploadOptions) error {
+	backend, err := s.storage.Backend(box.StorageBackendID)
+	if err != nil {
+		return err
+	}
 
 	for _, header := range files {
 		if !opts.SkipSizeLimit {
 			if err := s.ValidateSize(header.Size); err != nil {
-				return UploadResult{}, err
+				return err
 			}
 		}
 
@@ -245,7 +305,7 @@ func (s *UploadService) CreateBox(files []*multipart.FileHeader, opts UploadOpti
 
 		file, err := header.Open()
 		if err != nil {
-			return UploadResult{}, err
+			return err
 		}
 
 		fileID := randomID(8)
@@ -263,7 +323,7 @@ func (s *UploadService) CreateBox(files []*multipart.FileHeader, opts UploadOpti
 
 		if err := s.writeUploadedObject(context.Background(), backend, objectKey, file, header.Size, maxSize, contentType); err != nil {
 			file.Close()
-			return UploadResult{}, err
+			return err
 		}
 		file.Close()
 
@@ -278,20 +338,7 @@ func (s *UploadService) CreateBox(files []*multipart.FileHeader, opts UploadOpti
 			UploadedAt:  time.Now().UTC(),
 		})
 	}
-
+	return nil
-	if err := s.SaveBox(box); err != nil {
-		return UploadResult{}, err
-	}
-
-	s.logger.Info("upload complete",
-		"source", "user-upload",
-		"severity", "user_activity",
-		"code", 2001,
-		"box_id", box.ID,
-		"file_count", len(box.Files),
-	)
-
-	return s.resultForBox(box, deleteToken), nil
 }
 
 func (s *UploadService) GetBox(id string) (Box, error) {
@@ -730,13 +777,22 @@ func (s *UploadService) resultForBox(box Box, deleteToken string) UploadResult {
 			Name:         file.Name,
 			Size:         helpers.FormatBytes(file.Size),
 			URL:          fmt.Sprintf("%s/d/%s/f/%s", s.baseURL, box.ID, file.ID),
+			ThumbnailURL: fmt.Sprintf("%s/d/%s/thumb/%s", s.baseURL, box.ID, file.ID),
 		})
 	}
 
+	// The box-level thumbnail points at the most recently added file, so a
+	// per-file ShareX upload previews the file it just sent.
+	thumbnailURL := fmt.Sprintf("%s/d/%s/og-image.jpg", s.baseURL, box.ID)
+	if len(files) > 0 {
+		thumbnailURL = files[len(files)-1].ThumbnailURL
+	}
+
 	result := UploadResult{
 		BoxID:        box.ID,
 		BoxURL:       fmt.Sprintf("%s/d/%s", s.baseURL, box.ID),
 		ZipURL:       fmt.Sprintf("%s/d/%s/zip", s.baseURL, box.ID),
+		ThumbnailURL: thumbnailURL,
 		ExpiresAt:    box.ExpiresAt.Format(time.RFC3339),
 		Files:        files,
 	}

backend/static/css/40-docs.css

@@ -36,6 +36,22 @@
   font-size: 1rem;
 }
 
+.docs-card h3 {
+  margin: 1.35rem 0 0;
+  font-size: 0.9rem;
+  font-weight: 650;
+  color: var(--foreground);
+}
+
+/* Highlights where the API token goes in the ShareX config snippet. */
+.sxcu-highlight {
+  background: #fde047;
+  color: #1a1a1a;
+  font-weight: 700;
+  padding: 0 0.2rem;
+  border-radius: 3px;
+}
+
 .docs-card p {
   margin: 0.65rem 0 0;
   color: var(--muted-foreground);

backend/templates/layouts/base.html

@@ -60,7 +60,7 @@
   </main>
 
   <footer class="site-footer">
-    <span>{{.AppName}} · {{.AppVersion}} · {{.CurrentYear}} · self-hosted</span>
+    <span>{{.AppName}} · {{.AppVersion}} · {{.CurrentYear}}</span>
     <label class="theme-picker">
       <span>Theme</span>
       <select data-theme-select aria-label="Site theme">

backend/templates/pages/admin_user_edit.html

@@ -52,7 +52,7 @@
         <div class="table-header">
           <div>
             <h2>Identity and limits</h2>
-            <p>Blank limit fields inherit the global user defaults. Use -1 for unlimited upload size or daily upload caps. Storage quota set to 0 means unlimited.</p>
+            <p>Blank limit fields inherit the global user defaults. Use <code>-1</code> for unlimited in any limit field — upload size, daily caps, storage quota, max expiration (the box can then last forever), daily boxes, active boxes, and short-window requests. Storage quota <code>0</code> also means unlimited.</p>
           </div>
         </div>
         <form class="settings-form" action="/admin/users/{{.Data.UserEdit.ID}}/edit" method="post">
@@ -89,10 +89,10 @@
             <h3 class="settings-section-title">Upload limits</h3>
             <label><span>Max upload size (MB)</span><input name="max_upload_mb" value="{{.Data.UserEdit.MaxUploadMB}}" placeholder="inherit"></label>
             <label><span>Daily upload cap (MB)</span><input name="daily_upload_mb" value="{{.Data.UserEdit.DailyUploadMB}}" placeholder="inherit"></label>
-            <label><span>Max expiration (days)</span><input type="number" min="1" name="max_days" value="{{.Data.UserEdit.MaxDays}}" placeholder="inherit"></label>
+            <label><span>Max expiration (days)</span><input type="number" min="-1" name="max_days" value="{{.Data.UserEdit.MaxDays}}" placeholder="inherit"></label>
-            <label><span>Daily boxes</span><input type="number" min="1" name="daily_boxes" value="{{.Data.UserEdit.DailyBoxes}}" placeholder="inherit"></label>
+            <label><span>Daily boxes</span><input type="number" min="-1" name="daily_boxes" value="{{.Data.UserEdit.DailyBoxes}}" placeholder="inherit"></label>
-            <label><span>Active boxes</span><input type="number" min="1" name="active_boxes" value="{{.Data.UserEdit.ActiveBoxes}}" placeholder="inherit"></label>
+            <label><span>Active boxes</span><input type="number" min="-1" name="active_boxes" value="{{.Data.UserEdit.ActiveBoxes}}" placeholder="inherit"></label>
-            <label><span>Short-window requests</span><input type="number" min="1" name="short_window_requests" value="{{.Data.UserEdit.ShortWindowRequests}}" placeholder="inherit"></label>
+            <label><span>Short-window requests</span><input type="number" min="-1" name="short_window_requests" value="{{.Data.UserEdit.ShortWindowRequests}}" placeholder="inherit"></label>
           </div>
 
           <button class="button button-primary" type="submit">Save user</button>

backend/templates/pages/api.html

@@ -36,11 +36,12 @@
     <article class="card docs-card">
       <div class="card-content">
         <h2>JSON response</h2>
-        <p>The raw delete token is returned only once inside <code>manageUrl</code> and <code>deleteUrl</code>. Keep those links private.</p>
+        <p>The raw delete token is returned only once inside <code>manageUrl</code> and <code>deleteUrl</code>. Keep those links private. On error the body is <code>{ "error": "message" }</code> with a non-2xx status (e.g. rate limited or over a limit).</p>
         <pre><code>{
   "boxId": "abc123",
   "boxUrl": "{{.Data.BaseURL}}/d/abc123",
   "zipUrl": "{{.Data.BaseURL}}/d/abc123/zip",
+  "thumbnailUrl": "{{.Data.BaseURL}}/d/abc123/thumb/file123",
   "manageUrl": "{{.Data.BaseURL}}/d/abc123/manage/private-token",
   "deleteUrl": "{{.Data.BaseURL}}/d/abc123/manage/private-token/delete",
   "expiresAt": "2026-06-05T12:00:00Z",
@@ -49,7 +50,8 @@
       "id": "file123",
       "name": "report.pdf",
       "size": "2.4 MiB",
-      "url": "{{.Data.BaseURL}}/d/abc123/f/file123"
+      "url": "{{.Data.BaseURL}}/d/abc123/f/file123",
+      "thumbnailUrl": "{{.Data.BaseURL}}/d/abc123/thumb/file123"
     }
   ]
 }</code></pre>
@@ -59,22 +61,44 @@
     <article class="card docs-card">
       <div class="card-content">
         <h2>ShareX setup</h2>
+        <p>Import the uploader, then add your API key to upload as your account — with your account's size, daily, and retention limits — instead of as an anonymous guest.</p>
+
+        <h3>1 · Import the uploader</h3>
         <ol class="docs-steps">
-          <li>Download the instance config: <a href="/api/v1/sharex/warpbox-anonymous.sxcu"><code>/api/v1/sharex/warpbox-anonymous.sxcu</code></a>.</li>
+          <li>Download <a href="/api/v1/sharex/warpbox-anonymous.sxcu"><code>warpbox-anonymous.sxcu</code></a>.</li>
-          <li>Or open the tracked template at <code>{{.Data.ShareXExamplePath}}</code> and change <code>RequestURL</code> to <code>{{.Data.ShareXExampleURL}}</code>.</li>
+          <li>In ShareX: <code>Destinations → Custom uploader settings → Import → From file</code>, then pick the <code>.sxcu</code>.</li>
-          <li>Keep <code>FileFormName</code> as <code>{{.Data.ShareXFileFieldName}}</code>.</li>
-          <li>Import the <code>.sxcu</code> file into ShareX as a custom uploader.</li>
-          <li>Upload a file. ShareX will use <code>boxUrl</code> as the public URL and <code>manageUrl</code> as the deletion URL.</li>
         </ol>
+
+        <h3>2 · Add your API key (upload as your account)</h3>
+        <ol class="docs-steps">
+          <li>Create a personal access token under <a href="/account/settings">Account → Access tokens</a> and copy it.</li>
+          <li>In <code>Custom uploader settings</code>, select the Warpbox uploader and open the <code>Headers</code> section.</li>
+          <li>Add a header — Name <code>Authorization</code>, Value <code>Bearer &lt;your token&gt;</code>.</li>
+        </ol>
+        <p class="muted-copy">Without that header, uploads stay anonymous. With it, they're attributed to your account and use your account's limits.</p>
+
         <pre><code>{
+  "Version": "1.0.0",
+  "Name": "Warpbox (my account)",
+  "DestinationType": "ImageUploader, FileUploader, TextUploader",
   "RequestMethod": "POST",
   "RequestURL": "{{.Data.ShareXExampleURL}}",
-  "Headers": { "Accept": "application/json" },
+  "Headers": {
+    "Accept": "application/json",
+    "Authorization": "Bearer <span class="sxcu-highlight">YOUR_API_TOKEN</span>",
+    "X-Warpbox-Batch": "sharex"
+  },
   "Body": "MultipartFormData",
   "FileFormName": "{{.Data.ShareXFileFieldName}}",
-  "URL": "$json:boxUrl$",
+  "URL": "{json:boxUrl}",
-  "DeletionURL": "$json:manageUrl$"
+  "ThumbnailURL": "{json:thumbnailUrl}",
+  "DeletionURL": "{json:deleteUrl}",
+  "ErrorMessage": "{json:error}"
 }</code></pre>
+
+        <h3>Grouping multiple files into one box</h3>
+        <p>Grouping is <strong>opt-in via the <code>X-Warpbox-Batch</code> request header</strong> — without it, every file becomes its own box (the default). When the header is present, uploads sharing the same value (per account, or per IP for anonymous) within {{.Data.ShareXGroupWindow}} of each other are added to the <strong>same</strong> box, so a multi-file ShareX selection produces one shareable link instead of one per file. The shipped config sets <code>X-Warpbox-Batch: sharex</code>; remove that header for one box per file.</p>
+        <p class="muted-copy">The response also exposes <code>{json:thumbnailUrl}</code> for ShareX previews, <code>{json:deleteUrl}</code> for the deletion URL, and <code>{json:error}</code> so ShareX surfaces messages like rate limiting.</p>
       </div>
     </article>
 

examples/sharex/warpbox-anonymous.sxcu

@@ -5,10 +5,13 @@
   "RequestMethod": "POST",
   "RequestURL": "https://warpbox.dev/api/v1/upload",
   "Headers": {
-    "Accept": "application/json"
+    "Accept": "application/json",
+    "X-Warpbox-Batch": "sharex"
   },
   "Body": "MultipartFormData",
   "FileFormName": "sharex",
-  "URL": "$json:boxUrl$",
+  "URL": "{json:boxUrl}",
-  "DeletionURL": "$json:manageUrl$"
+  "ThumbnailURL": "{json:thumbnailUrl}",
+  "DeletionURL": "{json:deleteUrl}",
+  "ErrorMessage": "{json:error}"
 }