Check --keep-newer-than before the backup starts (closes #307)

snapshot create read --keep-newer-than only in the post-backup prune,
so a value the duration parser rejects failed the run after the
snapshot was uploaded: a nightly cron line added a snapshot each night,
reported it as failed, and never deleted any. Without --prune the flag
was ignored. The command now checks the flag before it starts and fails
on an invalid duration or a missing --prune.

A failed post-backup prune is now wrapped in ErrPostBackupPruneFailed
and reported as "Backup completed, but post-backup prune failed: ..."
rather than as a failed snapshot creation. The exit status stays 1.

Model: opus-5-5

README.md

@@ -286,7 +286,9 @@ needed.
   remove orphaned blobs from remote storage. By default keeps only the latest
   snapshot per name; use `--keep-newer-than` for a rolling window.
 * `--keep-newer-than <duration>`: With `--prune`, keep snapshots newer than
-  this duration instead of only the latest (e.g. `4w`, `30d`, `6mo`, `1y`)
+  this duration instead of only the latest (e.g. `4w`, `30d`, `6mo`, `1y`).
+  Without `--prune`, or with a value that is not a valid duration, the
+  command fails before the backup starts.
 
 **`snapshot list`**: Show every snapshot known to this host — the union
 of the local index and the backup destination store — with timestamps
@@ -349,9 +351,11 @@ the backup destination store. Blobs are NOT touched — deleting blobs
 requires reading every remaining remote manifest (the destination store
 may hold snapshots this host doesn't know about), which is what
 `vaultik prune` does. On success the command prints the exact `vaultik
-prune` invocation to run as a follow-up. Local row cleanup (files,
-chunks, blobs the snapshot was the last referrer for) runs
-automatically. If the destination store is unreachable, the local-DB
+prune` invocation to run as a follow-up. An ID that names no snapshot in
+the local index or on the destination store is an error; with
+`--local-only`, the snapshot must be in the local index. Local row
+cleanup (files, chunks, blobs the snapshot was the last referrer for)
+runs automatically. If the destination store is unreachable, the local-DB
 removal still completes and a warning is emitted; run `vaultik snapshot
 remove <snapshot-id>` again once the store is reachable to remove the
 snapshot's metadata from it (`vaultik prune` does not). To wipe everything
@@ -382,12 +386,10 @@ manifest on the destination store to compute the still-referenced blob
 set and delete any blob not in that set. Step (3) reads all remote
 manifests — network cost scales with the number of snapshots. `snapshot
 create --prune` runs the same cleanup automatically; this is the
-manual entry point for the same work. If a blob cannot be deleted, the
-command (and `snapshot create --prune`) exits non-zero.
+manual entry point for the same work.
 * `--force`: Skip confirmation prompt
 * `--json`: Output stats as JSON. Also skips the confirmation prompt, as
-  `--force` does. A blob that cannot be deleted is counted in
-  `blobs_failed`, and the document is printed before the non-zero exit.
+  `--force` does.
 
 **`info`**: Display system configuration, storage settings, encryption
 recipients, and local database statistics.
@@ -407,8 +409,7 @@ snapshot's blob count and blob size unknown, `null` in `--json`.
 **`remote nuke`**: Delete every snapshot's metadata and every blob from the
 backup destination store, leaving the bucket prefix empty. Destructive and
 irreversible. This is the single supported way to wipe the entire
-destination store. If anything cannot be deleted, the command exits
-non-zero; running it again deletes what is left.
+destination store.
 * `--force`: Required to confirm destruction.
 
 **`database delete`**: Delete the local SQLite state database file

TODO.md

@@ -22,16 +22,15 @@ the tag exists and is exercised; what is left is merging `next` to
 
 # Completed Steps
 
-- 2026-10-13: Made `prune` and `remote nuke` exit non-zero when a delete
-  fails ([issue #290](https://git.eeqj.de/sneak/vaultik/issues/290)).
-  `prune`, and the prune step of `snapshot create --prune`, counted a
-  blob it could not delete and still exited 0; it now prints its summary
-  or `--json` document and then fails. `remote nuke` warned about a
-  snapshot's metadata it could not delete, said to run `vaultik prune`,
-  which never removes metadata, and then reported the store empty. It
-  now fails without that report and says to run `vaultik remote nuke
-  --force` again, and a successful nuke no longer advises `prune` for
-  blobs it deletes itself.
+- 2026-10-13: Made `snapshot remove` fail for a snapshot that does not
+  exist ([issue #293](https://git.eeqj.de/sneak/vaultik/issues/293)).
+  The command never checked the ID: it reported the snapshot removed
+  from the local database and from the destination store and exited 0,
+  under `--json`, `--dry-run` and `--local-only` too. An ID that names
+  no snapshot in the local index or on the destination store is now an
+  error; with `--local-only`, the snapshot must be in the local index.
+  The command now reports a removal from either side only when one
+  happened, and `remote_removed` is true only when metadata was deleted.
 
 - 2026-10-12: Bound the local index to the destination an `s3.*` config
   names ([issue #298](https://git.eeqj.de/sneak/vaultik/issues/298)).

internal/cli/entry_snapshot_create_prune_test.go

@@ -0,0 +1,108 @@
+package cli //nolint:testpackage // shares runEntry and the hermetic config helpers
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// Flags of `snapshot create` used to build argument vectors below.
+const (
+	flagPrune         = "--prune"
+	flagKeepNewerThan = "--keep-newer-than"
+)
+
+// TestEntrySnapshotCreateRejectsKeepNewerThanBeforeBackup checks that a
+// --keep-newer-than the post-backup prune could not use stops `snapshot
+// create` before the backup: the command fails and the destination
+// store stays empty. It used to be read only by the prune, after the
+// snapshot was uploaded, and without --prune it was ignored.
+//
+//nolint:paralleltest // replaces os.Args, os.Stdout, os.Stderr and the xdg globals
+func TestEntrySnapshotCreateRejectsKeepNewerThanBeforeBackup(t *testing.T) {
+	for _, testCase := range []struct {
+		name string
+		args []string
+	}{
+		{
+			name: "decimal in a day count",
+			args: []string{flagPrune, flagKeepNewerThan, "1.5d"},
+		},
+		{
+			name: "unknown unit",
+			args: []string{flagPrune, flagKeepNewerThan, "4x"},
+		},
+		{
+			name: "without --prune",
+			args: []string{flagKeepNewerThan, "4w"},
+		},
+	} {
+		t.Run(testCase.name, func(t *testing.T) {
+			configPath, storeDir := writeBackupConfig(t)
+
+			code, _, _ := runEntry(t, append(
+				[]string{flagConfig, configPath, cmdSnapshot, cmdCreate},
+				testCase.args...)...)
+
+			assert.Equal(t, 1, code)
+
+			stored, err := os.ReadDir(storeDir)
+			require.NoError(t, err)
+			assert.Empty(t, stored, "nothing may be uploaded")
+		})
+	}
+}
+
+// TestEntrySnapshotCreateReportsPostBackupPruneFailure makes the
+// post-backup prune fail after a good backup, by planting a manifest
+// that cannot be decoded, and checks that the failure is reported as the
+// prune's and not as a failed snapshot creation.
+//
+//nolint:paralleltest // replaces os.Args, os.Stdout, os.Stderr and the xdg globals
+func TestEntrySnapshotCreateReportsPostBackupPruneFailure(t *testing.T) {
+	configPath, storeDir := writeBackupConfig(t)
+
+	// A remote key is 64 lowercase hex characters. The prune reads every
+	// manifest on the store and fails on one it cannot decode.
+	plantedDir := filepath.Join(storeDir, "metadata", strings.Repeat("a", 64))
+	require.NoError(t, os.MkdirAll(plantedDir, 0o750))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(plantedDir, "manifest.json.zst"),
+		[]byte("not a valid manifest"), 0o600))
+
+	code, _, stderr := runEntry(t,
+		flagConfig, configPath, cmdSnapshot, cmdCreate, flagPrune)
+
+	assert.Equal(t, 1, code)
+	assert.Contains(t, stderr, "Backup completed, but post-backup prune failed")
+	assert.NotContains(t, stderr, "Snapshot creation failed")
+
+	snapshots, err := os.ReadDir(filepath.Join(storeDir, "metadata"))
+	require.NoError(t, err)
+	assert.Len(t, snapshots, 2,
+		"the new snapshot is on the store beside the planted one")
+}
+
+// writeBackupConfig builds a hermetic config with one small file in its
+// source directory and an empty destination store directory. Returns the
+// config path and the store directory.
+func writeBackupConfig(t *testing.T) (string, string) {
+	t.Helper()
+
+	configPath := writeHermeticPruneConfig(t, false)
+
+	// writeHermeticPruneConfig puts the source and store directories
+	// beside the config file.
+	dir := filepath.Dir(configPath)
+	sourceDir := filepath.Join(dir, "source")
+
+	require.NoError(t, os.Mkdir(sourceDir, 0o750))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(sourceDir, "file.txt"), []byte("hello"), 0o600))
+
+	return configPath, filepath.Join(dir, "store")
+}

internal/cli/snapshot.go

@@ -71,6 +71,11 @@ otherwise from the platform config directory (~/.config/vaultik/config.yml
 on Linux), then /etc/vaultik/config.yml.`,
 		Args: cobra.ArbitraryArgs,
 		RunE: func(cmd *cobra.Command, args []string) error {
+			err := opts.Validate()
+			if err != nil {
+				return err
+			}
+
 			// Pass snapshot names from args
 			opts.Snapshots = args
 			// --skip-errors is a global flag on the root command.
@@ -97,6 +102,13 @@ on Linux), then /etc/vaultik/config.yml.`,
 			}, func(v *vaultik.Vaultik) error {
 				return v.CreateSnapshot(opts)
 			}, func(err error) {
+				if errors.Is(err, vaultik.ErrPostBackupPruneFailed) {
+					log.Error("Post-backup prune failed", "error", err)
+					ReportErrorf("Backup completed, but %v", err)
+
+					return
+				}
+
 				log.Error("Snapshot creation failed", "error", err)
 				ReportErrorf("Snapshot creation failed: %v", err)
 			})
@@ -255,8 +267,12 @@ manifest (the destination store may hold snapshots this host doesn't
 know about), which is what 'vaultik prune' does. On success the command
 prints the exact 'vaultik prune' invocation to run as a follow-up.
 
+An ID that names no snapshot in the local index or on the destination
+store is an error.
+
 Use --local-only to skip the remote half (e.g. when you want to forget a
-snapshot locally without touching the destination store).
+snapshot locally without touching the destination store); the snapshot
+must then be in the local index.
 
 If the remote is unreachable, the local-database removal still completes
 and a warning is emitted; run 'vaultik snapshot remove <snapshot-id>' again

internal/storage/faultstore/faultstore.go

@@ -1,16 +1,15 @@
 // Package faultstore provides a storage.Storer wrapper that injects
 // faults on demand, so tests can reproduce the failure modes a real
 // backend exhibits: an upload that fails partway, a backend that reports
-// success while storing nothing, reads that return corrupt or truncated
-// bytes, and a delete the backend refuses. It is the seam called for by
-// the fault-injection tests (sneak/vaultik issue 72) and is meant to be
-// reused by future tests rather than re-implemented per case.
+// success while storing nothing, and reads that return corrupt or
+// truncated bytes. It is the seam called for by the fault-injection
+// tests (sneak/vaultik issue 72) and is meant to be reused by future
+// tests rather than re-implemented per case.
 //
-// The wrapper delegates every method to the inner Storer. Three hooks
-// change that: OnPut decides the fate of each write, OnGet decides how
-// each read's bytes are returned, and OnDelete decides whether each
-// delete fails. All are keyed by the object key, so a test can fault
-// only blobs, only metadata, or a single object.
+// The wrapper delegates every method to the inner Storer. Two hooks
+// change that: OnPut decides the fate of each write, and OnGet decides
+// how each read's bytes are returned. Both are keyed by the object key,
+// so a test can fault only blobs, only metadata, or a single object.
 package faultstore
 
 import (
@@ -26,10 +25,6 @@ import (
 // ErrInjectedUpload is returned by a Put the OnPut hook chose to fail.
 var ErrInjectedUpload = errors.New("faultstore: injected upload failure")
 
-// ErrInjectedDelete is returned by a Delete the OnDelete hook chose to
-// fail.
-var ErrInjectedDelete = errors.New("faultstore: injected delete failure")
-
 // PutAction is the disposition OnPut assigns to a write.
 type PutAction int
 
@@ -71,11 +66,6 @@ type Storer struct {
 	// OnGet, when set, is consulted for every Get with the object key
 	// and damages the returned bytes accordingly.
 	OnGet func(key string) GetFault
-
-	// OnDelete, when set, is consulted before every Delete with the
-	// object key. Returning true fails the delete and leaves the object
-	// in place.
-	OnDelete func(key string) bool
 }
 
 // New wraps inner. inner must be non-nil.
@@ -164,12 +154,8 @@ func (f *Storer) Stat(ctx context.Context, key string) (*storage.ObjectInfo, err
 	return f.inner.Stat(ctx, key)
 }
 
-// Delete removes the object unless OnDelete fails the delete.
+// Delete delegates unchanged.
 func (f *Storer) Delete(ctx context.Context, key string) error {
-	if f.OnDelete != nil && f.OnDelete(key) {
-		return fmt.Errorf("%w for %q", ErrInjectedDelete, key)
-	}
-
 	return f.inner.Delete(ctx, key)
 }
 

internal/vaultik/nuke_remote_test.go

@@ -5,14 +5,12 @@ import (
 	"io/fs"
 	"os"
 	"path/filepath"
-	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"sneak.berlin/go/vaultik/internal/log"
 	"sneak.berlin/go/vaultik/internal/snapshot"
-	"sneak.berlin/go/vaultik/internal/storage/faultstore"
 )
 
 // TestNukeRemoteLeavesNoFiles checks that remote nuke leaves no file
@@ -25,7 +23,7 @@ func TestNukeRemoteLeavesNoFiles(t *testing.T) {
 
 	ctx := context.Background()
 	storeDir := filepath.Join(t.TempDir(), "store")
-	v, repos, out := backUpToFileDestination(ctx, t, storeDir)
+	v, repos, _ := backUpToFileDestination(ctx, t, storeDir)
 
 	snapshots, err := repos.Snapshots.ListRecent(ctx, listRecentTestLimit)
 	require.NoError(t, err)
@@ -63,62 +61,4 @@ func TestNukeRemoteLeavesNoFiles(t *testing.T) {
 		})
 	require.NoError(t, err)
 	assert.Empty(t, files)
-
-	// Nuke deletes the blobs itself, so advice to run prune is wrong.
-	assert.Contains(t, out.String(), "Backup destination store is now empty.")
-	assert.NotContains(t, out.String(), "vaultik prune")
-}
-
-// TestNukeRemoteFailsWhenADeleteFails checks that remote nuke returns an
-// error when a snapshot's metadata or a blob cannot be deleted, does not
-// report the store empty, and advises running nuke again: prune deletes
-// no metadata.
-func TestNukeRemoteFailsWhenADeleteFails(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	for _, refusedPrefix := range []string{"metadata/", "blobs/"} {
-		t.Run(refusedPrefix, func(t *testing.T) {
-			t.Parallel()
-
-			ctx := context.Background()
-			storeDir := filepath.Join(t.TempDir(), "store")
-			v, _, out := backUpToFileDestination(ctx, t, storeDir)
-
-			store := faultstore.New(v.Storage)
-			store.OnDelete = func(key string) bool {
-				return strings.HasPrefix(key, refusedPrefix)
-			}
-			v.Storage = store
-
-			require.Error(t, v.NukeRemote(true))
-
-			assert.NotContains(t, out.String(), "now empty")
-			assert.Contains(t, out.String(), "vaultik remote nuke --force")
-			assert.NotContains(t, out.String(), "vaultik prune")
-		})
-	}
-}
-
-// TestNukeRemoteFailsWhenALocalSnapshotCannotBeRemoved checks that a
-// snapshot remote nuke cannot remove from the local index fails the
-// run: nuke then leaves that snapshot's metadata on the destination
-// store.
-func TestNukeRemoteFailsWhenALocalSnapshotCannotBeRemoved(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	ctx := context.Background()
-	storeDir := filepath.Join(t.TempDir(), "store")
-	v, _, out := backUpToFileDestination(ctx, t, storeDir)
-
-	_, err := v.DB.Conn().ExecContext(ctx, `
-		CREATE TRIGGER refuse_snapshot_delete BEFORE DELETE ON snapshots
-		BEGIN SELECT RAISE(ABORT, 'simulated index error'); END`)
-	require.NoError(t, err)
-
-	require.Error(t, v.NukeRemote(true))
-
-	assert.NotContains(t, out.String(), "now empty")
-	assert.Contains(t, out.String(), "vaultik remote nuke --force")
 }

internal/vaultik/prune.go

@@ -19,14 +19,6 @@ type PruneOptions struct {
 var errNukeRequiresForce = errors.New(
 	"nuke requires --force (this deletes ALL remote snapshots and blobs)")
 
-// errBlobDeleteFailed reports unreferenced blobs prune could not delete.
-var errBlobDeleteFailed = errors.New("blob(s) could not be deleted")
-
-// nukeCommandHint is the command suggested when a remote nuke could not
-// delete everything: running it again deletes what is left, which
-// `vaultik prune` does not do for snapshot metadata.
-const nukeCommandHint = "vaultik remote nuke --force"
-
 // metadataDirName is the top-level remote directory holding snapshot
 // metadata.
 const metadataDirName = "metadata"
@@ -43,22 +35,6 @@ func (v *Vaultik) NukeRemote(force bool) error {
 		return errNukeRequiresForce
 	}
 
-	err := v.emptyDestinationStore()
-	if err != nil {
-		v.UI.Warningf("Run '%s' again to delete what is left on the "+
-			"backup destination store.", nukeCommandHint)
-
-		return err
-	}
-
-	v.UI.Completef("Backup destination store is now empty.")
-
-	return nil
-}
-
-// emptyDestinationStore does the deleting for NukeRemote and stops at
-// the first step that fails.
-func (v *Vaultik) emptyDestinationStore() error {
 	v.UI.Beginf("Removing all snapshot metadata from backup destination store.")
 
 	_, err := v.RemoveAllSnapshots(&RemoveOptions{Force: true})
@@ -82,6 +58,8 @@ func (v *Vaultik) emptyDestinationStore() error {
 		}
 	}
 
+	v.UI.Completef("Backup destination store is now empty.")
+
 	return nil
 }
 
@@ -184,17 +162,14 @@ func (v *Vaultik) PruneBlobs(opts *PruneOptions) error {
 	v.deleteUnreferencedBlobs(unreferencedBlobs, allBlobs, result)
 
 	if opts.JSON {
-		err = v.outputPruneBlobsJSON(result)
-		if err != nil {
-			return err
-		}
-	} else {
-		v.stdoutf("\nDeleted %d blob(s) totaling %s\n",
-			result.BlobsDeleted, ubytes(result.BytesFreed))
+		return v.outputPruneBlobsJSON(result)
 	}
 
+	v.stdoutf("\nDeleted %d blob(s) totaling %s\n",
+		result.BlobsDeleted, ubytes(result.BytesFreed))
+
 	if result.BlobsFailed > 0 {
-		return fmt.Errorf("%d %w", result.BlobsFailed, errBlobDeleteFailed)
+		v.stdoutf("Failed to delete %d blob(s)\n", result.BlobsFailed)
 	}
 
 	return nil

internal/vaultik/prune_delete_failure_test.go

@@ -1,98 +0,0 @@
-package vaultik_test
-
-import (
-	"context"
-	"encoding/json"
-	"os"
-	"path/filepath"
-	"strings"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"sneak.berlin/go/vaultik/internal/log"
-	"sneak.berlin/go/vaultik/internal/storage/faultstore"
-	"sneak.berlin/go/vaultik/internal/vaultik"
-)
-
-// refuseBlobDeletes is an OnDelete hook that fails every blob delete.
-func refuseBlobDeletes(key string) bool {
-	return strings.HasPrefix(key, "blobs/")
-}
-
-// TestPruneBlobs_FailedDeleteReturnsError checks that prune returns an
-// error, so the command exits non-zero, when an unreferenced blob cannot
-// be deleted.
-func TestPruneBlobs_FailedDeleteReturnsError(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	env := newListEnv(t)
-
-	// The store holds no manifest, so nothing references this blob.
-	addBlob(t, env.store.testStorer, testBlobHashA)
-
-	store := faultstore.New(env.store)
-	store.OnDelete = refuseBlobDeletes
-	env.v.Storage = store
-
-	err := env.v.PruneBlobs(&vaultik.PruneOptions{Force: true})
-
-	require.ErrorContains(t, err, "1 blob(s) could not be deleted")
-}
-
-// TestPruneBlobs_JSONFailedDeleteReturnsError checks that prune --json
-// prints its document and then returns an error when an unreferenced
-// blob cannot be deleted.
-func TestPruneBlobs_JSONFailedDeleteReturnsError(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	env := newListEnv(t)
-	addBlob(t, env.store.testStorer, testBlobHashA)
-
-	store := faultstore.New(env.store)
-	store.OnDelete = refuseBlobDeletes
-	env.v.Storage = store
-
-	err := env.v.PruneBlobs(&vaultik.PruneOptions{JSON: true})
-
-	require.Error(t, err, "prune must fail when a blob cannot be deleted")
-
-	var result vaultik.PruneBlobsResult
-
-	require.NoError(t, json.Unmarshal(env.stdout.Bytes(), &result),
-		"stdout must hold the JSON document, got:\n%s", env.stdout.String())
-	assert.Equal(t, 1, result.BlobsFailed)
-	assert.Equal(t, 0, result.BlobsDeleted)
-}
-
-// TestCreateSnapshotPrune_FailedBlobDeleteReturnsError checks that the
-// prune step of snapshot create --prune fails the run when an
-// unreferenced blob cannot be deleted.
-func TestCreateSnapshotPrune_FailedBlobDeleteReturnsError(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	ctx := context.Background()
-	storeDir := filepath.Join(t.TempDir(), "store")
-	v, _, _ := backUpToFileDestination(ctx, t, storeDir)
-
-	// No snapshot references this blob, so the prune step deletes it.
-	orphan := filepath.Join(storeDir, "blobs", testBlobHashA[:2],
-		testBlobHashA[2:4], testBlobHashA)
-	require.NoError(t, os.MkdirAll(filepath.Dir(orphan), 0o750))
-	require.NoError(t, os.WriteFile(orphan, []byte("orphan"), 0o600))
-
-	store := faultstore.New(v.Storage)
-	store.OnDelete = refuseBlobDeletes
-	v.Storage = store
-
-	err := v.CreateSnapshot(&vaultik.SnapshotCreateOptions{
-		Cron:  true,
-		Prune: true,
-	})
-
-	require.Error(t, err, "the prune step must fail the run")
-	assert.FileExists(t, orphan)
-}

internal/vaultik/remove_snapshot_test.go

@@ -3,17 +3,21 @@ package vaultik_test
 import (
 	"bytes"
 	"context"
+	"database/sql"
 	"io"
 	"strings"
 	"sync"
 	"testing"
+	"time"
 
 	"github.com/klauspost/compress/zstd"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/vaultik/internal/database"
 	"sneak.berlin/go/vaultik/internal/log"
 	"sneak.berlin/go/vaultik/internal/snapshot"
 	"sneak.berlin/go/vaultik/internal/storage"
+	"sneak.berlin/go/vaultik/internal/types"
 	"sneak.berlin/go/vaultik/internal/vaultik"
 )
 
@@ -214,6 +218,37 @@ func addBlob(t *testing.T, store *testStorer, hash string) {
 	require.NoError(t, err)
 }
 
+// newLocalIndex returns an in-memory local index holding a completed
+// snapshot row for each of ids.
+func newLocalIndex(t *testing.T, ids ...string) *database.Repositories {
+	t.Helper()
+
+	ctx := context.Background()
+
+	db, err := database.New(ctx, ":memory:")
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = db.Close() })
+
+	repos := database.NewRepositories(db)
+
+	for _, id := range ids {
+		completedAt := time.Now().UTC()
+		snap := &database.Snapshot{
+			ID:          types.SnapshotID(id),
+			Hostname:    snapHostname,
+			StartedAt:   completedAt,
+			CompletedAt: &completedAt,
+		}
+
+		err = repos.WithTx(ctx, func(ctx context.Context, tx *sql.Tx) error {
+			return repos.Snapshots.Create(ctx, tx, snap)
+		})
+		require.NoError(t, err)
+	}
+
+	return repos
+}
+
 // ============================================================================
 // Unit Tests for RemoveSnapshot
 // ============================================================================
@@ -233,6 +268,7 @@ func TestRemoveSnapshot_LocalOnly_PreservesRemote(t *testing.T) {
 	addBlob(t, store, blobA)
 
 	tv := vaultik.NewForTesting(store)
+	tv.Repositories = newLocalIndex(t, "snapshot-001")
 
 	opts := &vaultik.RemoveOptions{Force: true, LocalOnly: true}
 	result, err := tv.RemoveSnapshot("snapshot-001", opts)
@@ -268,6 +304,7 @@ func TestRemoveSnapshot_DefaultRemovesMetadataNotBlobs(t *testing.T) {
 	addBlob(t, store, blobShared)
 
 	tv := vaultik.NewForTesting(store)
+	tv.Repositories = newLocalIndex(t, "snapshot-001", "snapshot-002")
 
 	opts := &vaultik.RemoveOptions{Force: true}
 	result, err := tv.RemoveSnapshot("snapshot-001", opts)
@@ -316,6 +353,84 @@ func TestRemoveSnapshot_DryRun(t *testing.T) {
 	assert.Contains(t, tv.Stdout.String(), "[Dry run - no changes made]")
 }
 
+// TestRemoveSnapshot_UnknownIDIsError checks that an ID naming no
+// snapshot in the local index or on the destination store is an error
+// under every option, and that nothing is reported as removed.
+func TestRemoveSnapshot_UnknownIDIsError(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	for name, opts := range map[string]vaultik.RemoveOptions{
+		"force":      {Force: true},
+		"json":       {JSON: true},
+		"dry-run":    {Force: true, DryRun: true},
+		"local-only": {Force: true, LocalOnly: true},
+	} {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			store := newTestStorer()
+			addManifest(t, store, "snapshot-001", nil)
+
+			tv := vaultik.NewForTesting(store)
+			tv.Repositories = newLocalIndex(t, "snapshot-001")
+
+			result, err := tv.RemoveSnapshot("snapshot-999", &opts)
+
+			require.ErrorContains(t, err, "snapshot not found")
+			assert.False(t, result.RemoteRemoved)
+			assert.Empty(t, tv.Stdout.String())
+			assert.True(t, store.hasKey(remoteKeyPath("snapshot-001")))
+		})
+	}
+}
+
+// TestRemoveSnapshot_NoMetadataOnDestination checks that removing a
+// snapshot whose metadata is not on the destination store does not
+// report metadata removed from it.
+func TestRemoveSnapshot_NoMetadataOnDestination(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	tv := vaultik.NewForTesting(newTestStorer())
+	tv.Repositories = newLocalIndex(t, "snapshot-001")
+
+	result, err := tv.RemoveSnapshot("snapshot-001",
+		&vaultik.RemoveOptions{Force: true})
+
+	require.NoError(t, err)
+	assert.False(t, result.RemoteRemoved)
+
+	out := tv.Stdout.String()
+	assert.Contains(t, out, "Removed snapshot 'snapshot-001' from local database")
+	assert.NotContains(t, out, "Removed snapshot metadata from remote storage")
+}
+
+// TestRemoveSnapshot_NotInLocalIndex checks that removing a snapshot
+// only the destination store holds removes its metadata there without
+// reporting a removal from the local database.
+func TestRemoveSnapshot_NotInLocalIndex(t *testing.T) {
+	log.Initialize(log.Config{})
+	t.Parallel()
+
+	store := newTestStorer()
+	addManifest(t, store, "snapshot-001", nil)
+
+	tv := vaultik.NewForTesting(store)
+	tv.Repositories = newLocalIndex(t)
+
+	result, err := tv.RemoveSnapshot("snapshot-001",
+		&vaultik.RemoveOptions{Force: true})
+
+	require.NoError(t, err)
+	assert.True(t, result.RemoteRemoved)
+	assert.False(t, store.hasKey(remoteKeyPath("snapshot-001")))
+
+	out := tv.Stdout.String()
+	assert.NotContains(t, out, "from local database")
+	assert.Contains(t, out, "Removed snapshot metadata from remote storage")
+}
+
 func TestRemoveAllSnapshots_RequiresForce(t *testing.T) {
 	log.Initialize(log.Config{})
 	t.Parallel()
@@ -361,8 +476,7 @@ func TestRemoveAllSnapshots_WithForce(t *testing.T) {
 	out := tv.Stdout.String()
 	assert.Contains(t, out, "Removed 2 snapshot(s)")
 	assert.Contains(t, out, "Removed snapshot metadata from remote storage")
-	// Remote nuke, the only caller, deletes the blobs next itself.
-	assert.NotContains(t, out, "vaultik prune")
+	assert.Contains(t, out, "vaultik prune")
 }
 
 func TestRemoveAllSnapshots_DryRun(t *testing.T) {

internal/vaultik/snapshot.go

@@ -23,13 +23,19 @@ var (
 	errNoSnapshotsInConfig  = errors.New("no snapshots configured")
 	errSnapshotVerifyFailed = errors.New("verification failed")
 	errRemoveAllNeedsForce  = errors.New("--all requires --force")
-	errSnapshotRemoveFailed = errors.New("snapshot(s) could not be removed")
+	errSnapshotNotFound     = errors.New("snapshot not found")
 	errInvalidTableName     = errors.New("invalid table name")
 	errNoAgeRecipients      = errors.New(
 		"creating a snapshot needs at least one public key in " +
 			"age_recipients (generate a keypair with: age-keygen)")
+	errKeepNewerThanNeedsPrune = errors.New("--keep-newer-than requires --prune")
 )
 
+// ErrPostBackupPruneFailed wraps a failure of the post-backup prune,
+// which runs only after every snapshot was created and uploaded, so the
+// caller can report it apart from a failed backup.
+var ErrPostBackupPruneFailed = errors.New("post-backup prune failed")
+
 // listRecentLimit caps how many snapshot rows are fetched from the
 // local index for listing and purge operations.
 const listRecentLimit = 10000
@@ -45,6 +51,26 @@ type SnapshotCreateOptions struct {
 	Snapshots     []string // Optional list of snapshot names to process (empty = all)
 }
 
+// Validate fails when KeepNewerThan is set without Prune or is not a
+// valid duration. Only the post-backup prune reads KeepNewerThan, after
+// the backup, so the caller checks it before starting one.
+func (opts *SnapshotCreateOptions) Validate() error {
+	if opts.KeepNewerThan == "" {
+		return nil
+	}
+
+	if !opts.Prune {
+		return errKeepNewerThanNeedsPrune
+	}
+
+	_, err := parseDuration(opts.KeepNewerThan)
+	if err != nil {
+		return fmt.Errorf("--keep-newer-than: %w", err)
+	}
+
+	return nil
+}
+
 // CreateSnapshot executes the snapshot creation operation
 func (v *Vaultik) CreateSnapshot(opts *SnapshotCreateOptions) error {
 	// config.Load accepts an empty list, since listing, verifying and
@@ -123,7 +149,7 @@ func (v *Vaultik) CreateSnapshot(opts *SnapshotCreateOptions) error {
 	if opts.Prune {
 		err = v.runPostBackupPrune(snapshotNames, opts.KeepNewerThan)
 		if err != nil {
-			return fmt.Errorf("post-backup prune: %w", err)
+			return fmt.Errorf("%w: %w", ErrPostBackupPruneFailed, err)
 		}
 	}
 
@@ -644,7 +670,7 @@ func (v *Vaultik) confirmAndExecutePurge(
 				"snapshot_id", snapshotID, "error", err)
 		}
 
-		err = v.deleteRemoteSnapshotByKey(snapshot.RemoteSnapshotKey(snapshotID))
+		_, err = v.deleteRemoteSnapshotByKey(snapshot.RemoteSnapshotKey(snapshotID))
 		if err != nil {
 			return fmt.Errorf("deleting snapshot %s from remote: %w", snapshotID, err)
 		}
@@ -1154,6 +1180,11 @@ func (v *Vaultik) RemoveSnapshot(
 		return result, err
 	}
 
+	inLocalIndex, err := v.findSnapshotToRemove(snapshotID, opts)
+	if err != nil {
+		return result, err
+	}
+
 	if opts.DryRun {
 		return v.removeSnapshotDryRun(result, snapshotID, opts)
 	}
@@ -1162,11 +1193,13 @@ func (v *Vaultik) RemoveSnapshot(
 		return result, nil
 	}
 
-	log.Info("Removing snapshot from local database", "snapshot_id", snapshotID)
+	if inLocalIndex {
+		log.Info("Removing snapshot from local database", "snapshot_id", snapshotID)
 
-	err = v.deleteSnapshotFromLocalDB(snapshotID)
-	if err != nil {
-		return result, fmt.Errorf("removing from local database: %w", err)
+		err = v.deleteSnapshotFromLocalDB(snapshotID)
+		if err != nil {
+			return result, fmt.Errorf("removing from local database: %w", err)
+		}
 	}
 
 	if !opts.LocalOnly {
@@ -1185,9 +1218,11 @@ func (v *Vaultik) RemoveSnapshot(
 		return result, v.outputRemoveJSON(result)
 	}
 
-	v.stdoutf("Removed snapshot '%s' from local database\n", snapshotID)
+	if inLocalIndex {
+		v.stdoutf("Removed snapshot '%s' from local database\n", snapshotID)
+	}
 
-	if !opts.LocalOnly && result.RemoteRemoved {
+	if result.RemoteRemoved {
 		v.printlnStdout("Removed snapshot metadata from remote storage")
 		v.stdoutf("\nNote: The removed snapshot's blobs remain on the remote. "+
 			"Run '%s' to delete any blobs no longer referenced by any "+
@@ -1197,6 +1232,45 @@ func (v *Vaultik) RemoveSnapshot(
 	return result, nil
 }
 
+// findSnapshotToRemove reports whether the local index has a row for
+// snapshotID, and returns errSnapshotNotFound when there is nothing to
+// remove: no row and, unless LocalOnly is set, no metadata on the
+// destination store either. The destination store is consulted only
+// when the local index has no row, so a snapshot in the local index can
+// still be removed from it while the destination store is unreachable.
+func (v *Vaultik) findSnapshotToRemove(
+	snapshotID string, opts *RemoveOptions,
+) (bool, error) {
+	if v.Repositories != nil {
+		snap, err := v.Repositories.Snapshots.GetByID(v.ctx, snapshotID)
+		if err != nil {
+			return false, fmt.Errorf("looking up snapshot in local index: %w", err)
+		}
+
+		if snap != nil {
+			return true, nil
+		}
+	}
+
+	if opts.LocalOnly {
+		return false, fmt.Errorf("%w in the local index: %s",
+			errSnapshotNotFound, snapshotID)
+	}
+
+	objects, err := v.remoteSnapshotObjects(snapshot.RemoteSnapshotKey(snapshotID))
+	if err != nil {
+		return false, fmt.Errorf("looking up snapshot on destination store: %w", err)
+	}
+
+	if len(objects) == 0 {
+		return false, fmt.Errorf(
+			"%w in the local index or on the destination store: %s",
+			errSnapshotNotFound, snapshotID)
+	}
+
+	return false, nil
+}
+
 // removeSnapshotDryRun reports what RemoveSnapshot would do without
 // making changes.
 func (v *Vaultik) removeSnapshotDryRun(
@@ -1256,14 +1330,14 @@ func (v *Vaultik) confirmRemoveSnapshot(snapshotID string, opts *RemoveOptions)
 // didn't finish and to run `vaultik snapshot remove` for the snapshot
 // again once the destination store is reachable (`vaultik prune` never
 // removes snapshot metadata). Returns true when the remote removal
-// succeeded.
+// succeeded and deleted something.
 func (v *Vaultik) removeSnapshotRemote(snapshotID string, opts *RemoveOptions) bool {
 	log.Info("Removing snapshot metadata from remote storage",
 		"snapshot_id", snapshotID)
 
 	remoteKey := snapshot.RemoteSnapshotKey(snapshotID)
 
-	err := v.deleteRemoteSnapshotByKey(remoteKey)
+	deleted, err := v.deleteRemoteSnapshotByKey(remoteKey)
 	if err != nil {
 		log.Warn("Could not remove snapshot metadata from remote storage; "+
 			"run '"+snapshotRemoveCommandHint+"' with the snapshot's ID "+
@@ -1281,7 +1355,7 @@ func (v *Vaultik) removeSnapshotRemote(snapshotID string, opts *RemoveOptions) b
 		return false
 	}
 
-	return true
+	return deleted > 0
 }
 
 // RemoveAllSnapshots removes every snapshot known to the local
@@ -1465,8 +1539,8 @@ func (v *Vaultik) handleRemoveAllDryRun(
 
 // executeRemoveAll deletes every local snapshot and, unless LocalOnly
 // is set, every corresponding remote metadata directory plus any
-// orphan remote keys. Blobs are not touched. It returns an error when
-// any snapshot could not be removed.
+// orphan remote keys. Blobs are not touched; the printed prune-command
+// hint is the next step.
 func (v *Vaultik) executeRemoveAll(
 	localSnaps, orphanRemoteKeys []string, opts *RemoveOptions,
 ) (*RemoveResult, error) {
@@ -1480,11 +1554,18 @@ func (v *Vaultik) executeRemoveAll(
 
 	result := &RemoveResult{}
 
-	failures := v.removeAllLocalSnapshots(localSnaps, opts, result)
+	remoteErrors := v.removeAllLocalSnapshots(localSnaps, opts, result)
 
 	if !opts.LocalOnly {
-		failures += v.removeAllOrphanRemotes(orphanRemoteKeys, result)
-		result.RemoteRemoved = failures == 0
+		remoteErrors += v.removeAllOrphanRemotes(orphanRemoteKeys, result)
+
+		if remoteErrors == 0 {
+			result.RemoteRemoved = true
+		} else if v.UI != nil {
+			v.UI.Warningf("Some remote metadata deletions failed. Run '%s' "+
+				"once the remote is healthy to clean up unreferenced blobs.",
+				pruneCommandHint)
+		}
 	}
 
 	if v.SnapshotManager != nil {
@@ -1494,10 +1575,6 @@ func (v *Vaultik) executeRemoveAll(
 		}
 	}
 
-	if failures > 0 {
-		return result, fmt.Errorf("%d %w", failures, errSnapshotRemoveFailed)
-	}
-
 	if opts.JSON {
 		return result, v.outputRemoveJSON(result)
 	}
@@ -1506,6 +1583,9 @@ func (v *Vaultik) executeRemoveAll(
 
 	if !opts.LocalOnly && result.RemoteRemoved {
 		v.printlnStdout("Removed snapshot metadata from remote storage")
+		v.stdoutf("\nNote: Removed snapshots' blobs remain on the remote. "+
+			"Run '%s' to delete any blobs no longer referenced by any "+
+			"remaining remote snapshot.\n", pruneCommandHint)
 	}
 
 	return result, nil
@@ -1548,13 +1628,12 @@ func (v *Vaultik) deleteIncompleteSnapshot(snapshotIDStr string, id any) bool {
 }
 
 // removeAllLocalSnapshots removes each known local snapshot (and, unless
-// --local-only, its remote metadata), returning the number of snapshots
-// it could not remove. A snapshot left in the local index keeps its
-// remote metadata too, since it is not an orphan remote key.
+// --local-only, its remote metadata), returning the number of remote
+// deletion failures.
 func (v *Vaultik) removeAllLocalSnapshots(
 	localSnaps []string, opts *RemoveOptions, result *RemoveResult,
 ) int {
-	failures := 0
+	remoteErrors := 0
 
 	for _, snapshotID := range localSnaps {
 		log.Info("Removing snapshot", "snapshot_id", snapshotID)
@@ -1564,26 +1643,24 @@ func (v *Vaultik) removeAllLocalSnapshots(
 			log.Error("Failed to remove from local database",
 				"snapshot_id", snapshotID, "error", err)
 
-			failures++
-
 			continue
 		}
 
 		if !opts.LocalOnly {
-			err = v.deleteRemoteSnapshotByKey(
+			_, err = v.deleteRemoteSnapshotByKey(
 				snapshot.RemoteSnapshotKey(snapshotID))
 			if err != nil {
 				log.Warn("Failed to remove snapshot metadata from remote",
 					"snapshot_id", snapshotID, "error", err)
 
-				failures++
+				remoteErrors++
 			}
 		}
 
 		result.SnapshotsRemoved = append(result.SnapshotsRemoved, snapshotID)
 	}
 
-	return failures
+	return remoteErrors
 }
 
 // removeAllOrphanRemotes deletes remote snapshot metadata that has no
@@ -1596,7 +1673,7 @@ func (v *Vaultik) removeAllOrphanRemotes(
 	for _, key := range orphanRemoteKeys {
 		log.Info("Removing orphan remote snapshot", "remote_key", key)
 
-		err := v.deleteRemoteSnapshotByKey(key)
+		_, err := v.deleteRemoteSnapshotByKey(key)
 		if err != nil {
 			log.Warn("Failed to remove orphan from remote",
 				"remote_key", key, "error", err)
@@ -1643,34 +1720,44 @@ func (v *Vaultik) deleteSnapshotFromLocalDB(snapshotID string) error {
 }
 
 // deleteRemoteSnapshotByKey removes everything under
-// metadata/<remoteKey>/ on the destination store. The argument is a
-// remote key (double-SHA256 derivation), not a human snapshot ID;
-// callers that have a human ID must hash via snapshot.RemoteSnapshotKey
-// first.
-func (v *Vaultik) deleteRemoteSnapshotByKey(remoteKey string) error {
-	prefix := fmt.Sprintf("metadata/%s/", remoteKey)
-	objectCh := v.Storage.ListStream(v.ctx, prefix)
-
-	var objectsToDelete []string
-
-	for object := range objectCh {
-		if object.Err != nil {
-			return fmt.Errorf("listing objects: %w", object.Err)
-		}
-
-		objectsToDelete = append(objectsToDelete, object.Key)
+// metadata/<remoteKey>/ on the destination store and returns how many
+// objects it deleted. The argument is a remote key (double-SHA256
+// derivation), not a human snapshot ID; callers that have a human ID
+// must hash via snapshot.RemoteSnapshotKey first.
+func (v *Vaultik) deleteRemoteSnapshotByKey(remoteKey string) (int, error) {
+	objectsToDelete, err := v.remoteSnapshotObjects(remoteKey)
+	if err != nil {
+		return 0, err
 	}
 
-	for _, key := range objectsToDelete {
-		err := v.Storage.Delete(v.ctx, key)
+	for i, key := range objectsToDelete {
+		err = v.Storage.Delete(v.ctx, key)
 		if err != nil {
-			return fmt.Errorf("removing %s: %w", key, err)
+			return i, fmt.Errorf("removing %s: %w", key, err)
 		}
 
 		log.Debug("Deleted remote object", "key", key)
 	}
 
-	return nil
+	return len(objectsToDelete), nil
+}
+
+// remoteSnapshotObjects lists the keys of every object under
+// metadata/<remoteKey>/ on the destination store.
+func (v *Vaultik) remoteSnapshotObjects(remoteKey string) ([]string, error) {
+	prefix := fmt.Sprintf("metadata/%s/", remoteKey)
+
+	var keys []string
+
+	for object := range v.Storage.ListStream(v.ctx, prefix) {
+		if object.Err != nil {
+			return nil, fmt.Errorf("listing objects: %w", object.Err)
+		}
+
+		keys = append(keys, object.Key)
+	}
+
+	return keys, nil
 }
 
 // outputRemoveJSON outputs the removal result as JSON