Set the chart's placeholder version to 0.22.1

Cosmetic: make helm-package sets the published version and appVersion
from the tag, so these two fields decide nothing (see the comment
above them). Kept in step anyway, same as 71d7e18 and 734cd9c, so a
tree heading for v0.22.1 doesn't say 0.22.0.

Claude-Session: https://claude.ai/code/session_01MMados3BD1oSjevHxbmVqU

charts/terdut-server/Chart.yaml

@@ -15,5 +15,5 @@ type: application
 # appVersion and image.tag in values.yaml no longer agree, and that is not an oversight:
 # image.tag stays "latest", which is what a local install actually pulls. appVersion is
 # metadata and drives nothing.
-version: 0.21.0
-appVersion: "v0.21.0"
+version: 0.22.1
+appVersion: "v0.22.1"

internal/api/alertmanager.go

@@ -384,10 +384,10 @@ func openIncident(ctx context.Context, q querier, notify NotifyConfig, teamID in
 
 	var id int64
 	err = q.QueryRowContext(ctx, `
-		INSERT INTO incidents (team_id, group_key, title, group_labels, status, severity, triggered_at, assigned_to)
-		VALUES ($1, $2, $3, $4::jsonb, 'triggered', $5, $6, $7)
+		INSERT INTO incidents (team_id, group_key, title, group_labels, signature, status, severity, triggered_at, assigned_to)
+		VALUES ($1, $2, $3, $4::jsonb, $5, 'triggered', $6, $7, $8)
 		RETURNING id`,
-		teamID, groupKey, title, string(labelsJSON), severity,
+		teamID, groupKey, title, string(labelsJSON), incidentSignature(groupLabels, title), severity,
 		time.Now().Unix(), onCall).Scan(&id)
 	if err != nil {
 		return 0, err

internal/api/incident_store.go

@@ -36,6 +36,10 @@ const (
 	evUnsnoozed      = "unsnoozed"
 	evResolved       = "resolved"
 	evNote           = "note"
+	// evResolutionNote is the note worth finding again: what fixed it. The
+	// similar-incidents lookup and the page lead with these; plain notes are
+	// the working chatter and stay one click away.
+	evResolutionNote = "resolution_note"
 	evDeadmanSilent  = "deadman_silent"
 )
 
@@ -295,6 +299,34 @@ func openIncidentForAlert(ctx context.Context, q querier, alertID int64) (int64,
 	return id, err
 }
 
+// volatileLabels say where a problem ran this time, not what the problem is, so
+// they stay out of the signature. Migration 008's backfill lists the same set.
+var volatileLabels = map[string]bool{
+	"instance": true, "pod": true, "pod_name": true, "pod_ip": true,
+	"container": true, "container_name": true, "endpoint": true,
+}
+
+// incidentSignature identifies "the same problem" across incidents: the alert
+// name plus the stable group labels, sorted. Incidents in one team with equal
+// signatures are what the similar-incidents lookup returns. title stands in for
+// the name when the payload carried no alertname (groupless and dead man's
+// switch incidents).
+func incidentSignature(groupLabels map[string]string, title string) string {
+	name := groupLabels["alertname"]
+	if name == "" {
+		name = title
+	}
+	rest := make([]string, 0, len(groupLabels))
+	for k, v := range groupLabels {
+		if k == "alertname" || volatileLabels[k] {
+			continue
+		}
+		rest = append(rest, k+"="+v)
+	}
+	sort.Strings(rest)
+	return name + "|" + strings.Join(rest, ",")
+}
+
 // incidentTitle renders a human-readable title from Alertmanager's groupLabels,
 // leading with the alert name and appending whatever else the operator grouped
 // by. Falls back to the alert's own name when the payload carried no groupLabels.

internal/api/incidents.go

@@ -3,6 +3,7 @@ package api
 import (
 	"database/sql"
 	"fmt"
+	"io"
 	"net/http"
 	"strconv"
 	"strings"
@@ -237,6 +238,15 @@ func handleIncidentResolve(db *sql.DB) http.HandlerFunc {
 			return
 		}
 		user, _ := userFromContext(r.Context())
+		// The body is optional: clients that predate resolution notes send none.
+		var req struct {
+			Resolution string `json:"resolution"`
+		}
+		if err := decodeJSON(r, &req); err != nil && err != io.EOF {
+			respond(w, http.StatusBadRequest, errResp("invalid request body"))
+			return
+		}
+		req.Resolution = strings.TrimSpace(req.Resolution)
 		if !updateOpenIncident(w, r, db, id,
 			`UPDATE incidents SET status = 'resolved', resolved_at = $1, resolution_source = $2
 			  WHERE id = $3 AND resolved_at IS NULL`,
@@ -252,6 +262,12 @@ func handleIncidentResolve(db *sql.DB) http.HandlerFunc {
 			respond(w, http.StatusInternalServerError, errResp("internal error"))
 			return
 		}
+		if req.Resolution != "" {
+			if err := logEvent(r.Context(), db, id, evResolutionNote, &user.ID, nil, &req.Resolution); err != nil {
+				respond(w, http.StatusInternalServerError, errResp("internal error"))
+				return
+			}
+		}
 		respondIncident(w, r, db, id)
 	}
 }
@@ -421,11 +437,17 @@ func handleCreateNote(db *sql.DB) http.HandlerFunc {
 		}
 		var req struct {
 			Content string `json:"content"`
+			// Pinned files the note as the resolution note: what fixed it.
+			Pinned bool `json:"pinned"`
 		}
 		if err := decodeJSON(r, &req); err != nil {
 			respond(w, http.StatusBadRequest, errResp("invalid request body"))
 			return
 		}
+		noteType := evNote
+		if req.Pinned {
+			noteType = evResolutionNote
+		}
 		if req.Content == "" {
 			respond(w, http.StatusBadRequest, errResp("content is required"))
 			return
@@ -440,7 +462,7 @@ func handleCreateNote(db *sql.DB) http.HandlerFunc {
 		err := db.QueryRowContext(r.Context(), `
 			INSERT INTO incident_events (incident_id, type, user_id, detail, created_at)
 			VALUES ($1, $2, $3, $4, $5)
-			RETURNING id`, id, evNote, user.ID, req.Content, now.Unix()).Scan(&eventID)
+			RETURNING id`, id, noteType, user.ID, req.Content, now.Unix()).Scan(&eventID)
 		if err != nil {
 			respond(w, http.StatusInternalServerError, errResp("internal error"))
 			return
@@ -449,7 +471,7 @@ func handleCreateNote(db *sql.DB) http.HandlerFunc {
 		respond(w, http.StatusCreated, models.IncidentEvent{
 			ID:         eventID,
 			IncidentID: id,
-			Type:       evNote,
+			Type:       noteType,
 			UserID:     &user.ID,
 			Username:   &user.Username,
 			Detail:     &req.Content,
@@ -475,8 +497,8 @@ func handleDeleteNote(db *sql.DB) http.HandlerFunc {
 		user, _ := userFromContext(r.Context())
 		res, err := db.ExecContext(r.Context(), `
 			DELETE FROM incident_events
-			 WHERE id = $1 AND incident_id = $2 AND type = $3 AND user_id = $4`,
-			eventID, id, evNote, user.ID)
+			 WHERE id = $1 AND incident_id = $2 AND type IN ($3, $4) AND user_id = $5`,
+			eventID, id, evNote, evResolutionNote, user.ID)
 		if err != nil {
 			respond(w, http.StatusInternalServerError, errResp("internal error"))
 			return

internal/api/notifier.go

@@ -330,6 +330,16 @@ func deliver(ctx context.Context, db *sql.DB, cfg NotifyConfig, n outboxRow) err
 
 	msg := renderNotification(inc, n, firing, cfg)
 
+	// The page that opens an incident carries what fixed it last time, so the
+	// person woken up starts from that. Best effort: a failed lookup must not
+	// hold back the page itself.
+	if n.kind == notifyTriggered {
+		if sim, err := similarIncidents(ctx, db, n.incidentID, 1); err == nil && len(sim) > 0 && len(sim[0].ResolutionNotes) > 0 {
+			notes := sim[0].ResolutionNotes
+			msg.Message += "\nLast time: " + shorten(derefString(notes[len(notes)-1].Detail), 160)
+		}
+	}
+
 	// An Acknowledge button needs both a user to attribute the acknowledgement
 	// to and a URL the phone can reach. Minted per delivery, so every push
 	// carries its own short-lived token rather than reusing one.
@@ -573,6 +583,17 @@ func plural(n int) string {
 	return "s"
 }
 
+// shorten cuts s to at most n runes, marking the cut, and flattens newlines so
+// a multi-line note stays one line in a push.
+func shorten(s string, n int) string {
+	s = strings.Join(strings.Fields(s), " ")
+	r := []rune(s)
+	if len(r) <= n {
+		return s
+	}
+	return string(r[:n-1]) + "…"
+}
+
 // derefString reads a nullable text column as a plain string.
 func derefString(s *string) string {
 	if s == nil {

internal/api/router.go

@@ -112,6 +112,7 @@ func NewRouter(db *sql.DB, notify NotifyConfig, cfg config.Config) http.Handler
 		r.Get("/api/incidents/{id}", handleGetIncident(db))
 		r.Get("/api/incidents/{id}/alerts", handleIncidentAlerts(db))
 		r.Get("/api/incidents/{id}/timeline", handleIncidentTimeline(db))
+		r.Get("/api/incidents/{id}/similar", handleIncidentSimilar(db))
 		r.Post("/api/incidents/{id}/acknowledge", handleIncidentAcknowledge(db))
 		r.Delete("/api/incidents/{id}/acknowledge", handleIncidentUnacknowledge(db))
 		r.Post("/api/incidents/{id}/resolve", handleIncidentResolve(db))

internal/api/similar.go

@@ -0,0 +1,113 @@
+package api
+
+import (
+	"context"
+	"database/sql"
+	"net/http"
+	"strconv"
+	"time"
+
+	"git.ryuvia.com/niklas/terdut-server/internal/models"
+)
+
+const (
+	similarDefaultLimit = 5
+	similarMaxLimit     = 20
+)
+
+// handleIncidentSimilar lists earlier, resolved incidents in the same team with
+// the same signature that someone left notes on, incidents with a resolution
+// note first. This is the "have we seen this before" answer for a responder
+// looking at a fresh incident; the plain notes are one timeline fetch away.
+func handleIncidentSimilar(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, ok := incidentIDParam(w, r, db)
+		if !ok {
+			return
+		}
+		limit := similarDefaultLimit
+		if v := r.URL.Query().Get("limit"); v != "" {
+			n, err := strconv.Atoi(v)
+			if err != nil || n < 1 {
+				respond(w, http.StatusBadRequest, errResp("invalid limit"))
+				return
+			}
+			limit = min(n, similarMaxLimit)
+		}
+
+		out, err := similarIncidents(r.Context(), db, id, limit)
+		if err != nil {
+			respond(w, http.StatusInternalServerError, errResp("internal error"))
+			return
+		}
+		respond(w, http.StatusOK, out)
+	}
+}
+
+func similarIncidents(ctx context.Context, q querier, id int64, limit int) ([]models.SimilarIncident, error) {
+	rows, err := q.QueryContext(ctx, `
+		SELECT o.id, o.title, o.triggered_at, o.resolved_at,
+		       (SELECT COUNT(*) FROM incident_events e
+		         WHERE e.incident_id = o.id AND e.type = $3)
+		FROM   incidents i
+		JOIN   incidents o ON o.team_id = i.team_id AND o.signature = i.signature
+		WHERE  i.id = $1 AND o.id <> i.id AND o.resolved_at IS NOT NULL
+		  AND  EXISTS (SELECT 1 FROM incident_events e
+		                WHERE e.incident_id = o.id AND e.type IN ($3, $4))
+		ORDER  BY EXISTS (SELECT 1 FROM incident_events e
+		                   WHERE e.incident_id = o.id AND e.type = $4) DESC,
+		          o.triggered_at DESC
+		LIMIT  $2`, id, limit, evNote, evResolutionNote)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	out := []models.SimilarIncident{}
+	ids := []int64{}
+	for rows.Next() {
+		var s models.SimilarIncident
+		var triggered, resolved int64
+		if err := rows.Scan(&s.ID, &s.Title, &triggered, &resolved, &s.NoteCount); err != nil {
+			return nil, err
+		}
+		s.TriggeredAt = time.Unix(triggered, 0).UTC()
+		s.ResolvedAt = time.Unix(resolved, 0).UTC()
+		s.ResolutionNotes = []models.IncidentEvent{}
+		out = append(out, s)
+		ids = append(ids, s.ID)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	if len(out) == 0 {
+		return out, nil
+	}
+
+	nrows, err := q.QueryContext(ctx, `
+		SELECT e.id, e.incident_id, e.type, e.user_id, u.username, e.detail, e.created_at
+		FROM   incident_events e
+		LEFT   JOIN users u ON u.id = e.user_id
+		WHERE  e.incident_id = ANY($1) AND e.type = $2
+		ORDER  BY e.created_at, e.id`, ids, evResolutionNote)
+	if err != nil {
+		return nil, err
+	}
+	defer nrows.Close()
+
+	byID := make(map[int64]*models.SimilarIncident, len(out))
+	for i := range out {
+		byID[out[i].ID] = &out[i]
+	}
+	for nrows.Next() {
+		var e models.IncidentEvent
+		var ts int64
+		if err := nrows.Scan(&e.ID, &e.IncidentID, &e.Type, &e.UserID, &e.Username, &e.Detail, &ts); err != nil {
+			return nil, err
+		}
+		e.CreatedAt = time.Unix(ts, 0).UTC()
+		s := byID[e.IncidentID]
+		s.ResolutionNotes = append(s.ResolutionNotes, e)
+	}
+	return out, nrows.Err()
+}

internal/api/similar_test.go

@@ -0,0 +1,99 @@
+package api_test
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"strconv"
+	"testing"
+)
+
+// postGrouped posts a firing webhook whose group labels are exactly the given
+// map, unlike postWebhook, which only ever groups by alertname.
+func postGrouped(t *testing.T, s *ts, fingerprint, startsAt string, groupLabels map[string]string) {
+	t.Helper()
+	labels := map[string]string{}
+	for k, v := range groupLabels {
+		labels[k] = v
+	}
+	payload := map[string]any{
+		"version": "4", "status": "firing",
+		"groupKey":    fingerprint,
+		"groupLabels": groupLabels,
+		"alerts": []map[string]any{
+			amAlert(fingerprint, groupLabels["alertname"], "firing", startsAt, zeroTime, labels),
+		},
+	}
+	data, _ := json.Marshal(payload)
+	resp, err := http.Post(s.URL+"/api/integrations/"+s.ingestKey+"/alertmanager",
+		"application/json", bytes.NewReader(data))
+	if err != nil {
+		t.Fatalf("post webhook: %v", err)
+	}
+	resp.Body.Close()
+}
+
+func similar(t *testing.T, s *ts, id int) []map[string]any {
+	t.Helper()
+	var out []map[string]any
+	decode(t, s.req(t, http.MethodGet, "/api/incidents/"+strconv.Itoa(id)+"/similar", nil), &out)
+	return out
+}
+
+// Same alert on another instance is the same problem; a resolution note left on
+// the first one is what the second one should be shown.
+func TestSimilar_IgnoresVolatileLabelsAndLeadsWithResolutionNote(t *testing.T) {
+	s := newTS(t)
+	postGrouped(t, s, "fp-a", "2026-05-20T10:00:00Z",
+		map[string]string{"alertname": "DiskFull", "instance": "web-1", "job": "node"})
+	s.req(t, http.MethodPost, "/api/incidents/1/resolve",
+		map[string]string{"resolution": "rotated the logs"}).Body.Close()
+
+	postGrouped(t, s, "fp-b", "2026-05-21T10:00:00Z",
+		map[string]string{"alertname": "DiskFull", "instance": "web-2", "job": "node"})
+
+	got := similar(t, s, 2)
+	if len(got) != 1 || int(got[0]["id"].(float64)) != 1 {
+		t.Fatalf("expected incident 1 as the only similar one, got %v", got)
+	}
+	notes := got[0]["resolution_notes"].([]any)
+	if len(notes) != 1 || notes[0].(map[string]any)["detail"] != "rotated the logs" {
+		t.Fatalf("expected the resolution note, got %v", notes)
+	}
+}
+
+// A different stable label (job) is a different problem, and an incident nobody
+// wrote a note on has nothing to show.
+func TestSimilar_DifferentSignatureOrNoNotesIsExcluded(t *testing.T) {
+	s := newTS(t)
+	postGrouped(t, s, "fp-1", "2026-05-20T10:00:00Z",
+		map[string]string{"alertname": "DiskFull", "job": "node"})
+	s.req(t, http.MethodPost, "/api/incidents/1/notes", map[string]string{"content": "checked"}).Body.Close()
+	s.req(t, http.MethodPost, "/api/incidents/1/resolve", nil).Body.Close()
+
+	postGrouped(t, s, "fp-2", "2026-05-20T11:00:00Z",
+		map[string]string{"alertname": "DiskFull", "job": "db"})
+	s.req(t, http.MethodPost, "/api/incidents/2/resolve", nil).Body.Close()
+
+	postGrouped(t, s, "fp-3", "2026-05-21T10:00:00Z",
+		map[string]string{"alertname": "DiskFull", "job": "db"})
+
+	// Incident 3 matches 2 by signature, but 2 has no notes.
+	if got := similar(t, s, 3); len(got) != 0 {
+		t.Fatalf("expected nothing similar to incident 3, got %v", got)
+	}
+}
+
+// An open incident is not "earlier experience" yet, and the incident itself is
+// never its own match.
+func TestSimilar_OpenIncidentsAreNotListed(t *testing.T) {
+	s := newTS(t)
+	postGrouped(t, s, "fp-o1", "2026-05-20T10:00:00Z", map[string]string{"alertname": "Flap"})
+	s.req(t, http.MethodPost, "/api/incidents/1/notes",
+		map[string]any{"content": "still open", "pinned": true}).Body.Close()
+	postGrouped(t, s, "fp-o2", "2026-05-21T10:00:00Z", map[string]string{"alertname": "Flap"})
+
+	if got := similar(t, s, 2); len(got) != 0 {
+		t.Fatalf("expected an open incident not to be listed, got %v", got)
+	}
+}

internal/db/migrations/008_incident_signature.sql

@@ -0,0 +1,23 @@
+-- Similar incidents: a signature per incident, so "has this happened before"
+-- is an indexed equality instead of a search.
+--
+-- The signature is the alert name plus the group labels that identify WHAT is
+-- broken, minus the ones that only say WHERE it happened to run this time
+-- (instance, pod, ...). Two incidents with the same signature in the same team
+-- are the same problem for a responder's purposes.
+--
+-- Computed in Go for new incidents (incidentSignature in incident_store.go).
+-- The backfill below MUST produce the same string; keep the volatile list in
+-- both places in step.
+ALTER TABLE incidents ADD COLUMN signature TEXT NOT NULL DEFAULT '';
+
+UPDATE incidents SET signature =
+    COALESCE(NULLIF(group_labels->>'alertname', ''), title) || '|' ||
+    COALESCE((
+        SELECT string_agg(e.k || '=' || e.v, ',' ORDER BY e.k)
+          FROM jsonb_each_text(incidents.group_labels) AS e(k, v)
+         WHERE e.k <> 'alertname'
+           AND e.k NOT IN ('instance', 'pod', 'pod_name', 'pod_ip', 'container', 'container_name', 'endpoint')
+    ), '');
+
+CREATE INDEX incidents_signature_idx ON incidents(team_id, signature, triggered_at DESC);

internal/models/incident.go

@@ -79,3 +79,15 @@ type IncidentEvent struct {
 	Detail     *string   `json:"detail,omitempty"`
 	CreatedAt  time.Time `json:"created_at"`
 }
+
+// SimilarIncident is an earlier, resolved incident with the same signature as
+// the one being looked at. ResolutionNotes are the "what fixed it" notes;
+// NoteCount counts the plain working notes, which live on the timeline.
+type SimilarIncident struct {
+	ID              int64           `json:"id"`
+	Title           string          `json:"title"`
+	TriggeredAt     time.Time       `json:"triggered_at"`
+	ResolvedAt      time.Time       `json:"resolved_at"`
+	NoteCount       int             `json:"note_count"`
+	ResolutionNotes []IncidentEvent `json:"resolution_notes"`
+}

internal/web/static/app.css

@@ -450,11 +450,16 @@ details[open] > summary { margin-bottom: 8px; }
 .tl-text { overflow-wrap: anywhere; }
 .tl-text .who { font-weight: 650; }
 .tl-time { color: var(--faint); font-size: 12px; }
-.tl-note .note {
+.note {
   margin-top: 6px; padding: 10px 12px;
   background: var(--surface-2); border-radius: var(--radius-sm);
   white-space: pre-wrap; overflow-wrap: anywhere;
 }
+.note-fix { background: var(--ok-soft); border-left: 3px solid var(--ok); }
+.similar { list-style: none; margin: 0; padding: 0; }
+.similar-item { padding: 10px 0; }
+.similar-item + .similar-item { border-top: 1px solid var(--border, var(--surface-2)); }
+.check { display: flex; align-items: center; gap: 8px; font-size: 14px; color: var(--muted); }
 .note-actions { display: flex; justify-content: flex-end; }
 .note-actions .btn { color: var(--muted); }
 
@@ -633,6 +638,10 @@ kbd {
   .view-queue .pane { overflow: auto; height: 100dvh; }
   .pane-list { border-right: 1px solid var(--border); }
   .pane-list .chips { position: sticky; top: 0; z-index: 2; background: var(--bg); padding-top: 16px; }
+  /* The pane is 340-420px wide and a mouse cannot scroll a row whose scrollbar
+     is hidden, so the chips wrap here instead: Archived stays reachable. */
+  .pane-list .chips { flex-wrap: wrap; overflow-x: visible; }
+  .pane-list .chip-sep { display: none; }
   .view-queue:not(.has-detail) .pane-detail { display: block; }
 
   /* On desktop the list stays visible next to the detail. */

internal/web/static/js/api.js

@@ -83,13 +83,14 @@ export const timeline = (id) => call('GET', `/incidents/${id}/timeline`);
 
 export const acknowledge = (id) => call('POST', `/incidents/${id}/acknowledge`);
 export const unacknowledge = (id) => call('DELETE', `/incidents/${id}/acknowledge`);
-export const resolve = (id) => call('POST', `/incidents/${id}/resolve`);
+export const resolve = (id, resolution) => call('POST', `/incidents/${id}/resolve`, resolution ? { body: { resolution } } : {});
 export const assign = (id, userID) => call('POST', `/incidents/${id}/assign`, { body: { user_id: userID } });
 export const snooze = (id, spec) => call('POST', `/incidents/${id}/snooze`, { body: spec });
 export const unsnooze = (id) => call('DELETE', `/incidents/${id}/snooze`);
 export const archive = (id) => call('POST', `/incidents/${id}/archive`);
 export const unarchive = (id) => call('DELETE', `/incidents/${id}/archive`);
-export const addNote = (id, content) => call('POST', `/incidents/${id}/notes`, { body: { content } });
+export const addNote = (id, content, pinned = false) => call('POST', `/incidents/${id}/notes`, { body: { content, pinned } });
+export const similar = (id) => call('GET', `/incidents/${id}/similar`);
 export const deleteNote = (id, eventID) => call('DELETE', `/incidents/${id}/notes/${eventID}`);
 
 // stats

internal/web/static/js/incident.js

@@ -17,6 +17,7 @@ const pane = () => document.getElementById('detail');
 let currentID = null;
 let inc = null;
 let events = [];
+let similarList = [];
 let error = null;
 let busy = false;
 
@@ -38,10 +39,15 @@ export async function refresh() {
   const id = currentID;
   if (id == null) return;
   try {
-    const [i, t] = await Promise.all([api.incident(id), api.timeline(id)]);
+    // Similar incidents are a courtesy: an older server answers 404 and a
+    // failure here must not hide the incident itself.
+    const [i, t, sim] = await Promise.all([
+      api.incident(id), api.timeline(id), api.similar(id).catch(() => []),
+    ]);
     if (id !== currentID) return;
     inc = i;
     events = t;
+    similarList = sim;
     error = null;
   } catch (err) {
     if (id !== currentID) return;
@@ -81,6 +87,7 @@ function render() {
       facts(),
       groupLabels(),
       alertsSection(),
+      similarSection(),
       timelineSection(),
     ),
     actionBar(),
@@ -197,6 +204,7 @@ function eventText(ev) {
     case 'unsnoozed': return [strong(person), ' ended the snooze'];
     case 'resolved': return person ? [strong(person), ' resolved the incident'] : ['Resolved: every alert stopped firing'];
     case 'note': return [strong(person), ' added a note'];
+    case 'resolution_note': return [strong(person), ' noted what fixed it'];
     case 'notified': {
       const to = person ? strong(person) : 'the fallback topic';
       if (ev.detail === 'reminder') return ['Reminder sent to ', to];
@@ -209,6 +217,22 @@ function eventText(ev) {
   }
 }
 
+// Earlier incidents with the same signature that someone left notes on, the
+// ones that recorded what fixed it first. Plain notes are on that incident's
+// own page.
+function similarSection() {
+  if (!similarList.length) return null;
+  return h('section', { class: 'section' },
+    h('h2', { class: 'section-title' }, h('span', { text: 'Seen before' })),
+    h('div', { class: 'card' },
+      h('ul', { class: 'similar' }, similarList.map((s) => h('li', { class: 'similar-item' },
+        h('a', { href: `/incidents/${s.id}`, text: `#${s.id} ${s.title}` }),
+        h('div', { class: 'sub', text: `${when(s.resolved_at)} · ${ago(s.resolved_at)}${s.note_count ? ` · ${s.note_count} note${s.note_count === 1 ? '' : 's'}` : ''}` }),
+        ...s.resolution_notes.map((n) => h('div', { class: 'note note-fix', text: n.detail || '' })),
+      )))),
+  );
+}
+
 function timelineSection() {
   const sorted = [...events].sort((a, b) => Date.parse(a.created_at) - Date.parse(b.created_at) || a.id - b.id);
   return h('section', { class: 'section' },
@@ -223,14 +247,16 @@ function timelineSection() {
   );
 }
 
+const isNote = (ev) => ev.type === 'note' || ev.type === 'resolution_note';
+
 function timelineItem(ev) {
-  const mine = ev.type === 'note' && ev.user_id === myID();
+  const mine = isNote(ev) && ev.user_id === myID();
   return h('li', { class: `tl-item tl-${ev.type}` },
     h('span', { class: 'tl-dot' }),
     h('div', { class: 'tl-body' },
       h('div', { class: 'tl-text' }, eventText(ev)),
       h('div', { class: 'tl-time', title: ev.created_at, text: `${when(ev.created_at)} · ${ago(ev.created_at)}` }),
-      ev.type === 'note' && h('div', { class: 'note', text: ev.detail || '' }),
+      isNote(ev) && h('div', { class: ev.type === 'resolution_note' ? 'note note-fix' : 'note', text: ev.detail || '' }),
       mine && h('div', { class: 'note-actions' },
         h('button', { class: 'btn btn-ghost btn-sm', type: 'button', onclick: () => deleteNote(ev) }, icon('trash'), 'Delete')),
     ),
@@ -296,15 +322,35 @@ function unacknowledge() {
 
 async function resolve() {
   const id = inc.id;
-  const ok = await confirm({
-    title: 'Resolve this incident?',
-    text: 'Resolving is final. If these alerts fire again they open a new incident, '
-      + 'and if any are still firing this one stays closed regardless. '
-      + 'Use snooze if you only need it out of the way.',
-    confirmLabel: 'Resolve',
-    danger: true,
+  const res = await openSheet(() => {
+    const textarea = h('textarea', {
+      name: 'resolution', autofocus: true, maxlength: '10000',
+      placeholder: 'What fixed it? Optional, shown on the next similar incident.',
+    });
+    const form = h('form', {
+      class: 'sheet-form',
+      onsubmit: (e) => {
+        e.preventDefault();
+        closeSheet({ resolution: textarea.value.trim() });
+      },
+    },
+      h('h2', { class: 'sheet-title', text: 'Resolve this incident?' }),
+      h('p', {
+        text: 'Resolving is final. If these alerts fire again they open a new incident, '
+          + 'and if any are still firing this one stays closed regardless. '
+          + 'Use snooze if you only need it out of the way.',
+      }),
+      textarea,
+      h('div', { class: 'sheet-actions' },
+        h('button', { class: 'btn', type: 'button', onclick: () => closeSheet(null), text: 'Cancel' }),
+        h('button', { class: 'btn btn-danger', type: 'submit', text: 'Resolve' })),
+    );
+    textarea.addEventListener('keydown', (e) => {
+      if (e.key === 'Enter' && (e.ctrlKey || e.metaKey)) form.requestSubmit();
+    });
+    return form;
   });
-  if (ok) await run(() => api.resolve(id), 'Resolved');
+  if (res) await run(() => api.resolve(id, res.resolution), 'Resolved');
 }
 
 function archive() {
@@ -382,16 +428,18 @@ async function addNote() {
     const textarea = h('textarea', {
       name: 'content', required: true, autofocus: true, placeholder: 'What did you find? What did you do?', maxlength: '10000',
     });
+    const fix = h('input', { type: 'checkbox', name: 'fix' });
     const form = h('form', {
       class: 'sheet-form',
       onsubmit: (e) => {
         e.preventDefault();
         const v = textarea.value.trim();
-        if (v) closeSheet(v);
+        if (v) closeSheet({ content: v, pinned: fix.checked });
       },
     },
       h('h2', { class: 'sheet-title', text: 'Add note' }),
       textarea,
+      h('label', { class: 'check' }, fix, ' This is what fixed it (shown on similar incidents)'),
       h('div', { class: 'sheet-actions' },
         h('button', { class: 'btn', type: 'button', onclick: () => closeSheet(null), text: 'Cancel' }),
         h('button', { class: 'btn btn-primary', type: 'submit', text: 'Save note' })),
@@ -402,7 +450,7 @@ async function addNote() {
     });
     return form;
   });
-  if (content) await run(() => api.addNote(id, content), 'Note added');
+  if (content) await run(() => api.addNote(id, content.content, content.pinned), 'Note added');
 }
 
 async function deleteNote(ev) {