diff --git a/go/seats/nodeengine/contract.go b/go/seats/nodeengine/contract.go
index f8267e8..b0d565a 100644
--- a/go/seats/nodeengine/contract.go
+++ b/go/seats/nodeengine/contract.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strings"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -348,7 +349,7 @@ func DecodeFindingsByKeyValue(raw []byte) (FindingsByKeyValue, error) {
 // AccountsHanded is the hashes of the users of the list, sealed to the vault.
 type AccountsHanded struct {
 	// when
-	At   string    `json:"at"`
+	At   time.Time `json:"at"`
 	Box  SealedBox `json:"box"`
 	From string    `json:"from"`
 	// the fingerprint of the vault's key
@@ -557,8 +558,8 @@ type FailedUnit struct {
 	Result   string `json:"result,omitempty"`
 	Scope    string `json:"scope"`
 	// since when
-	Since string `json:"since"`
-	Unit  string `json:"unit"`
+	Since time.Time `json:"since"`
+	Unit  string    `json:"unit"`
 }
 
 // FindingAction is one answer the operator may give from a notification.
@@ -579,8 +580,8 @@ const (
 
 // FindingEvidence is one observation, as it was said.
 type FindingEvidence struct {
-	At   string `json:"at"`
-	Said string `json:"said"`
+	At   time.Time `json:"at"`
+	Said string    `json:"said"`
 }
 
 // FindingSubject is what the condition is about.
@@ -598,10 +599,10 @@ type FindingSubject struct {
 // LoginFallback is a login that fell back to another node.
 type LoginFallback struct {
 	// when
-	At   string `json:"at"`
-	From string `json:"from"`
-	Node string `json:"node"`
-	Why  string `json:"why"`
+	At   time.Time `json:"at"`
+	From string    `json:"from"`
+	Node string    `json:"node"`
+	Why  string    `json:"why"`
 }
 
 // ManifestReadsChanged is what a node-engine says when what it reads changed or its node returned (ADR 0618 §4).
@@ -651,7 +652,7 @@ const (
 type NetworkHealth struct {
 	Parts []NetworkPart `json:"parts"`
 	// since when
-	Since string `json:"since"`
+	Since time.Time `json:"since"`
 	// running, degraded or unknown
 	State string `json:"state"`
 }
@@ -663,12 +664,12 @@ type NetworkPart struct {
 	Reason string `json:"reason,omitempty"`
 	Said   string `json:"said,omitempty"`
 	// since when
-	Since   string   `json:"since"`
-	State   string   `json:"state"`
-	Streak  int64    `json:"streak,omitempty"`
-	Targets []string `json:"targets,omitempty"`
-	Toward  []string `json:"toward,omitempty"`
-	Writer  string   `json:"writer,omitempty"`
+	Since   time.Time `json:"since"`
+	State   string    `json:"state"`
+	Streak  int64     `json:"streak,omitempty"`
+	Targets []string  `json:"targets,omitempty"`
+	Toward  []string  `json:"toward,omitempty"`
+	Writer  string    `json:"writer,omitempty"`
 }
 
 // NodeAccount is an account the node needs to log in again.
@@ -678,7 +679,7 @@ type NodeAccount struct {
 	Reason   string `json:"reason"`
 	Resource string `json:"resource,omitempty"`
 	// since when
-	Since string `json:"since"`
+	Since time.Time `json:"since"`
 }
 
 // NodeDirectory is a directory found where the node expected none.
@@ -688,7 +689,7 @@ type NodeDirectory struct {
 	Reason   string `json:"reason"`
 	Resource string `json:"resource"`
 	// since when
-	Since string `json:"since"`
+	Since time.Time `json:"since"`
 }
 
 // NodeOwn is what a node's own composition carries beside its resources.
@@ -744,14 +745,14 @@ type PlacedDataItem struct {
 // PullWait is the pull from a store a failed apply waits on.
 type PullWait struct {
 	// when the pull began
-	Began string `json:"began"`
+	Began time.Time `json:"began"`
 	// that seat's holder, whose settling the apply waits for
 	Holder string `json:"holder"`
 	Image  string `json:"image"`
 	// what triggered the last try again, in words
 	Retried string `json:"retried,omitempty"`
 	// when the apply was last tried again
-	RetriedAt string `json:"retried-at,omitempty"`
+	RetriedAt *time.Time `json:"retried-at,omitempty"`
 	// the seat the pull came through
 	Seat string `json:"seat,omitempty"`
 }
@@ -779,8 +780,8 @@ type RootAccountVerdict struct {
 	Reason   string `json:"reason,omitempty"`
 	Resource string `json:"resource"`
 	// since when
-	Since string `json:"since"`
-	State string `json:"state"`
+	Since time.Time `json:"since"`
+	State string    `json:"state"`
 }
 
 // RootVerdict is the engine's root-free verdict (ADR 0563 §6).
@@ -859,7 +860,7 @@ type UnitsHealth struct {
 // UserListWritten is the bus's user list as the engine of the bus node wrote it to the bus module's file.
 type UserListWritten struct {
 	// when
-	At string `json:"at"`
+	At time.Time `json:"at"`
 	// the digest of the file on the machine after the write
 	Digest string `json:"digest,omitempty"`
 	// why a write failed
@@ -1361,7 +1362,7 @@ type PackagesByNodeValue struct {
 // HealthByNodeValue is one value of the state health under the key <node>.
 type HealthByNodeValue struct {
 	// when
-	At       string               `json:"at"`
+	At       time.Time            `json:"at"`
 	Contract int64                `json:"contract,omitempty"`
 	Fallback *LoginFallback       `json:"fallback,omitempty"`
 	Found    []NodeDirectory      `json:"found,omitempty"`
@@ -1377,7 +1378,7 @@ type HealthByNodeValue struct {
 // FindingsByKeyValue is one value of the state findings under the key <key>.
 type FindingsByKeyValue struct {
 	Actions []FindingAction `json:"actions,omitempty"`
-	At      string          `json:"at"`
+	At      time.Time       `json:"at"`
 	// newest first, at most 10
 	Evidence    []FindingEvidence `json:"evidence,omitempty"`
 	Explanation string            `json:"explanation,omitempty"`
diff --git a/health-and-repair/go/clients/meshconditionsclient/client.go b/health-and-repair/go/clients/meshconditionsclient/client.go
index 8e3a014..2931dc8 100644
--- a/health-and-repair/go/clients/meshconditionsclient/client.go
+++ b/health-and-repair/go/clients/meshconditionsclient/client.go
@@ -146,7 +146,7 @@ func CheckFinding(f seat.FindingsByKeyValue) error {
 
 // Order sorts conditions as a person reads them: urgent first, then oldest raised, then by key.
 func Order(list []seat.ConditionsByKeyValue) {
-	raised := func(c seat.ConditionsByKeyValue) time.Time { t, _ := time.Parse(time.RFC3339Nano, c.Raised); return t }
+	raised := func(c seat.ConditionsByKeyValue) time.Time { return c.Raised }
 	sort.SliceStable(list, func(i, j int) bool {
 		if list[i].Severity != list[j].Severity {
 			return list[i].Severity == Urgent
@@ -163,8 +163,8 @@ func SilencedAt(c seat.ConditionsByKeyValue, now time.Time) bool {
 	if c.Silenced == nil {
 		return false
 	}
-	until, err := time.Parse(time.RFC3339Nano, c.Silenced.Until)
-	return err == nil && now.Before(until)
+	until := c.Silenced.Until
+	return until != nil && now.Before(*until)
 }
 
 // Escalated says the condition waits on the operator after healers tried.
@@ -191,7 +191,7 @@ var _ views.FindingWriter = FindingWriter{}
 
 // FindingFor is the value and key of the seat's finding for f.
 func FindingFor(f views.Finding) seat.FindingsByKeyValue {
-	at := f.At.UTC().Format(time.RFC3339Nano)
+	at := f.At.UTC()
 	return seat.FindingsByKeyValue{V: FindingVersion, Key: Key(ScopeModule, f.ID, f.Kind), Kind: f.Kind,
 		Subject: seat.Subject{Scope: ScopeModule, ID: f.ID}, Severity: Warning, Summary: f.Summary, Headline: f.Headline,
 		Explanation: f.Explanation, Evidence: []seat.Evidence{{At: at, Said: f.Summary}}, Source: f.Observer + "." + f.Kind,
diff --git a/health-and-repair/go/clients/meshconditionsclient/client_test.go b/health-and-repair/go/clients/meshconditionsclient/client_test.go
index 746368a..c9ba6df 100644
--- a/health-and-repair/go/clients/meshconditionsclient/client_test.go
+++ b/health-and-repair/go/clients/meshconditionsclient/client_test.go
@@ -41,9 +41,9 @@ func TestAFindingsKeyAndTheOrderOfConditions(t *testing.T) {
 		}
 	}
 	list := []seat.ConditionsByKeyValue{
-		{Key: "b", Severity: Warning, Raised: "2026-11-01T10:00:00Z"},
-		{Key: "c", Severity: Urgent, Raised: "2026-11-02T10:00:00Z"},
-		{Key: "a", Severity: Urgent, Raised: "2026-11-01T10:00:00.5Z", Silenced: &seat.ConditionsByKeyValueSilenced{Until: "2026-11-03T00:00:00Z"}},
+		{Key: "b", Severity: Warning, Raised: when("2026-11-01T10:00:00Z")},
+		{Key: "c", Severity: Urgent, Raised: when("2026-11-02T10:00:00Z")},
+		{Key: "a", Severity: Urgent, Raised: when("2026-11-01T10:00:00.5Z"), Silenced: &seat.ConditionsByKeyValueSilenced{Until: ptr(when("2026-11-03T00:00:00Z"))}},
 	}
 	Order(list)
 	if got := list[0].Key + list[1].Key + list[2].Key; got != "acb" {
@@ -99,3 +99,13 @@ func TestTheFindingWriterWritesAndClearsAModulesFindingInTheSeatsLayout(t *testi
 		t.Error("a finding that says nothing was written")
 	}
 }
+
+func when(s string) time.Time {
+	t, err := time.Parse(time.RFC3339Nano, s)
+	if err != nil {
+		panic(err)
+	}
+	return t
+}
+
+func ptr(t time.Time) *time.Time { return &t }
diff --git a/health-and-repair/go/seats/meshconditions/contract.go b/health-and-repair/go/seats/meshconditions/contract.go
index eddd19d..0757680 100644
--- a/health-and-repair/go/seats/meshconditions/contract.go
+++ b/health-and-repair/go/seats/meshconditions/contract.go
@@ -7,6 +7,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -134,50 +135,50 @@ const (
 
 // ConditionEventGapsItem is a type of the contract.
 type ConditionEventGapsItem struct {
-	Cleared  string `json:"cleared,omitempty"`
-	Reopened string `json:"reopened,omitempty"`
+	Cleared  *time.Time `json:"cleared,omitempty"`
+	Reopened *time.Time `json:"reopened,omitempty"`
 }
 
 // ConditionEventSilenced is a type of the contract.
 type ConditionEventSilenced struct {
-	By    string `json:"by,omitempty"`
-	Since string `json:"since,omitempty"`
-	Until string `json:"until,omitempty"`
-	Why   string `json:"why,omitempty"`
+	By    string     `json:"by,omitempty"`
+	Since *time.Time `json:"since,omitempty"`
+	Until *time.Time `json:"until,omitempty"`
+	Why   string     `json:"why,omitempty"`
 }
 
 // ConditionEventTriedItem is a type of the contract.
 type ConditionEventTriedItem struct {
-	At      string `json:"at,omitempty"`
-	By      string `json:"by,omitempty"`
-	Outcome string `json:"outcome,omitempty"`
-	What    string `json:"what,omitempty"`
+	At      *time.Time `json:"at,omitempty"`
+	By      string     `json:"by,omitempty"`
+	Outcome string     `json:"outcome,omitempty"`
+	What    string     `json:"what,omitempty"`
 }
 
 // ConditionEvent is a condition and what changed.
 type ConditionEvent struct {
-	Actions []Action `json:"actions,omitempty"`
-	At      string   `json:"at"`
-	Change  string   `json:"change"`
-	Cleared string   `json:"cleared,omitempty"`
-	Count   int64    `json:"count,omitempty"`
-	Epoch   int64    `json:"epoch,omitempty"`
-	Event   string   `json:"event"`
+	Actions []Action   `json:"actions,omitempty"`
+	At      time.Time  `json:"at"`
+	Change  string     `json:"change"`
+	Cleared *time.Time `json:"cleared,omitempty"`
+	Count   int64      `json:"count,omitempty"`
+	Epoch   int64      `json:"epoch,omitempty"`
+	Event   string     `json:"event"`
 	// newest first, at most 10
 	Evidence    []Evidence               `json:"evidence,omitempty"`
 	Explanation string                   `json:"explanation,omitempty"`
-	First       string                   `json:"first,omitempty"`
+	First       *time.Time               `json:"first,omitempty"`
 	Gaps        []ConditionEventGapsItem `json:"gaps,omitempty"`
 	Headline    string                   `json:"headline,omitempty"`
 	// scope.id.token
-	Key          string `json:"key"`
-	Kind         string `json:"kind,omitempty"`
-	LastObserved string `json:"last-observed,omitempty"`
-	LooksUnread  string `json:"looks-unread,omitempty"`
-	Needs        string `json:"needs,omitempty"`
-	Observations int64  `json:"observations,omitempty"`
-	Raised       string `json:"raised,omitempty"`
-	Resolved     string `json:"resolved,omitempty"`
+	Key          string     `json:"key"`
+	Kind         string     `json:"kind,omitempty"`
+	LastObserved *time.Time `json:"last-observed,omitempty"`
+	LooksUnread  string     `json:"looks-unread,omitempty"`
+	Needs        string     `json:"needs,omitempty"`
+	Observations int64      `json:"observations,omitempty"`
+	Raised       *time.Time `json:"raised,omitempty"`
+	Resolved     string     `json:"resolved,omitempty"`
 	// self, operator, agent or healer:<name>
 	Resolver string `json:"resolver,omitempty"`
 	Severity string `json:"severity,omitempty"`
@@ -214,8 +215,8 @@ const (
 
 // Evidence is one observation, as it was said.
 type Evidence struct {
-	At   string `json:"at"`
-	Said string `json:"said"`
+	At   time.Time `json:"at"`
+	Said string    `json:"said"`
 }
 
 // Subject is what the condition is about.
@@ -288,24 +289,24 @@ type ConditionClearedEvent = ConditionEvent
 
 // ConditionsByKeyValueGapsItem is a type of the contract.
 type ConditionsByKeyValueGapsItem struct {
-	Cleared  string `json:"cleared,omitempty"`
-	Reopened string `json:"reopened,omitempty"`
+	Cleared  *time.Time `json:"cleared,omitempty"`
+	Reopened *time.Time `json:"reopened,omitempty"`
 }
 
 // ConditionsByKeyValueSilenced is a type of the contract.
 type ConditionsByKeyValueSilenced struct {
-	By    string `json:"by,omitempty"`
-	Since string `json:"since,omitempty"`
-	Until string `json:"until,omitempty"`
-	Why   string `json:"why,omitempty"`
+	By    string     `json:"by,omitempty"`
+	Since *time.Time `json:"since,omitempty"`
+	Until *time.Time `json:"until,omitempty"`
+	Why   string     `json:"why,omitempty"`
 }
 
 // ConditionsByKeyValueTriedItem is a type of the contract.
 type ConditionsByKeyValueTriedItem struct {
-	At      string `json:"at,omitempty"`
-	By      string `json:"by,omitempty"`
-	Outcome string `json:"outcome,omitempty"`
-	What    string `json:"what,omitempty"`
+	At      *time.Time `json:"at,omitempty"`
+	By      string     `json:"by,omitempty"`
+	Outcome string     `json:"outcome,omitempty"`
+	What    string     `json:"what,omitempty"`
 }
 
 // ConditionsByKeyValue is one value of the state conditions under the key <key>.
@@ -316,18 +317,18 @@ type ConditionsByKeyValue struct {
 	// newest first, at most 10
 	Evidence    []Evidence                     `json:"evidence,omitempty"`
 	Explanation string                         `json:"explanation,omitempty"`
-	First       string                         `json:"first,omitempty"`
+	First       *time.Time                     `json:"first,omitempty"`
 	Gaps        []ConditionsByKeyValueGapsItem `json:"gaps,omitempty"`
 	Headline    string                         `json:"headline,omitempty"`
 	// scope.id.token
-	Key          string `json:"key"`
-	Kind         string `json:"kind"`
-	LastObserved string `json:"last-observed"`
-	LooksUnread  string `json:"looks-unread,omitempty"`
-	Needs        string `json:"needs,omitempty"`
-	Observations int64  `json:"observations,omitempty"`
-	Raised       string `json:"raised"`
-	Resolved     string `json:"resolved,omitempty"`
+	Key          string    `json:"key"`
+	Kind         string    `json:"kind"`
+	LastObserved time.Time `json:"last-observed"`
+	LooksUnread  string    `json:"looks-unread,omitempty"`
+	Needs        string    `json:"needs,omitempty"`
+	Observations int64     `json:"observations,omitempty"`
+	Raised       time.Time `json:"raised"`
+	Resolved     string    `json:"resolved,omitempty"`
 	// self, operator, agent or healer:<name>
 	Resolver string                        `json:"resolver,omitempty"`
 	Severity string                        `json:"severity"`
@@ -348,8 +349,8 @@ const (
 
 // FindingsByKeyValue is one value of the state findings under the key <key>.
 type FindingsByKeyValue struct {
-	Actions []Action `json:"actions,omitempty"`
-	At      string   `json:"at"`
+	Actions []Action  `json:"actions,omitempty"`
+	At      time.Time `json:"at"`
 	// newest first, at most 10
 	Evidence    []Evidence `json:"evidence,omitempty"`
 	Explanation string     `json:"explanation,omitempty"`
diff --git a/health-and-repair/go/seats/meshhandacts/contract.go b/health-and-repair/go/seats/meshhandacts/contract.go
index dfe00ce..12c84db 100644
--- a/health-and-repair/go/seats/meshhandacts/contract.go
+++ b/health-and-repair/go/seats/meshhandacts/contract.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strings"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -116,9 +117,9 @@ func DecodeWarrantsByAskerAskValue(raw []byte) (WarrantsByAskerAskValue, error)
 
 // Act is one act done by hand.
 type Act struct {
-	Arguments []string `json:"arguments,omitempty"`
-	Ask       string   `json:"ask,omitempty"`
-	At        string   `json:"at"`
+	Arguments []string  `json:"arguments,omitempty"`
+	Ask       string    `json:"ask,omitempty"`
+	At        time.Time `json:"at"`
 	// the caller the runtime proved
 	By        string   `json:"by"`
 	Carried   []string `json:"carried,omitempty"`
@@ -191,9 +192,9 @@ type ActRecordedEvent = Act
 
 // ActsByIDValue is one value of the state acts under the key <id>.
 type ActsByIDValue struct {
-	Arguments []string `json:"arguments,omitempty"`
-	Ask       string   `json:"ask,omitempty"`
-	At        string   `json:"at"`
+	Arguments []string  `json:"arguments,omitempty"`
+	Ask       string    `json:"ask,omitempty"`
+	At        time.Time `json:"at"`
 	// the caller the runtime proved
 	By        string   `json:"by"`
 	Carried   []string `json:"carried,omitempty"`
@@ -214,9 +215,9 @@ type ActsByIDValue struct {
 
 // WarrantsByAskerAskValue is one value of the state warrants under the key <asker>.<ask>.
 type WarrantsByAskerAskValue struct {
-	Ask    string `json:"ask"`
-	Asker  string `json:"asker"`
-	At     string `json:"at,omitempty"`
-	By     string `json:"by,omitempty"`
-	Option string `json:"option,omitempty"`
+	Ask    string     `json:"ask"`
+	Asker  string     `json:"asker"`
+	At     *time.Time `json:"at,omitempty"`
+	By     string     `json:"by,omitempty"`
+	Option string     `json:"option,omitempty"`
 }
diff --git a/health-and-repair/go/seats/meshhealers/contract.go b/health-and-repair/go/seats/meshhealers/contract.go
index b26eaaf..4733ebc 100644
--- a/health-and-repair/go/seats/meshhealers/contract.go
+++ b/health-and-repair/go/seats/meshhealers/contract.go
@@ -7,6 +7,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -143,17 +144,17 @@ type DrillAnswer = map[string]any
 
 // HealerActedEvent is the body of the event healer-acted.
 type HealerActedEvent struct {
-	Act       string `json:"act,omitempty"`
-	At        string `json:"at"`
-	Budget    string `json:"budget,omitempty"`
-	By        string `json:"by,omitempty"`
-	Condition string `json:"condition"`
-	Event     string `json:"event"`
-	Healer    string `json:"healer"`
-	Kind      string `json:"kind,omitempty"`
-	Outcome   string `json:"outcome"`
-	Said      string `json:"said,omitempty"`
-	Show      string `json:"show,omitempty"`
+	Act       string    `json:"act,omitempty"`
+	At        time.Time `json:"at"`
+	Budget    string    `json:"budget,omitempty"`
+	By        string    `json:"by,omitempty"`
+	Condition string    `json:"condition"`
+	Event     string    `json:"event"`
+	Healer    string    `json:"healer"`
+	Kind      string    `json:"kind,omitempty"`
+	Outcome   string    `json:"outcome"`
+	Said      string    `json:"said,omitempty"`
+	Show      string    `json:"show,omitempty"`
 }
 
 // The values of HealerActedEvent's outcome.
@@ -166,16 +167,16 @@ const (
 
 // AttemptsByAttemptValue is one value of the state attempts under the key <attempt>.
 type AttemptsByAttemptValue struct {
-	Act   string `json:"act"`
-	Begun string `json:"begun"`
+	Act   string    `json:"act"`
+	Begun time.Time `json:"begun"`
 	// what the budget counts by: the condition's key unless the healer says another
-	BudgetKey string `json:"budget-key"`
-	Condition string `json:"condition"`
-	Finished  string `json:"finished,omitempty"`
-	Healer    string `json:"healer"`
-	Kind      string `json:"kind"`
-	Outcome   string `json:"outcome"`
-	Said      string `json:"said,omitempty"`
+	BudgetKey string     `json:"budget-key"`
+	Condition string     `json:"condition"`
+	Finished  *time.Time `json:"finished,omitempty"`
+	Healer    string     `json:"healer"`
+	Kind      string     `json:"kind"`
+	Outcome   string     `json:"outcome"`
+	Said      string     `json:"said,omitempty"`
 }
 
 // The values of AttemptsByAttemptValue's outcome.
@@ -188,10 +189,10 @@ const (
 
 // WouldByWouldValue is one value of the state would under the key <would>.
 type WouldByWouldValue struct {
-	Act       string `json:"act"`
-	At        string `json:"at"`
-	Condition string `json:"condition"`
-	Healer    string `json:"healer"`
-	Kind      string `json:"kind,omitempty"`
-	Why       string `json:"why,omitempty"`
+	Act       string    `json:"act"`
+	At        time.Time `json:"at"`
+	Condition string    `json:"condition"`
+	Healer    string    `json:"healer"`
+	Kind      string    `json:"kind,omitempty"`
+	Why       string    `json:"why,omitempty"`
 }
diff --git a/health-and-repair/go/seats/meshselfcheck/contract.go b/health-and-repair/go/seats/meshselfcheck/contract.go
index 2c67551..ad3b5cb 100644
--- a/health-and-repair/go/seats/meshselfcheck/contract.go
+++ b/health-and-repair/go/seats/meshselfcheck/contract.go
@@ -3,6 +3,8 @@
 // Package meshselfcheck is the contract of the seat "mesh-self-check", defined whole (seats/mesh-self-check/seat.json): The mesh checking itself (ADR 0564): probes run every five minutes, each failure a finding the seat's conditions raise.
 package meshselfcheck
 
+import "time"
+
 // Seat is the seat's name.
 const Seat = "mesh-self-check"
 
@@ -88,13 +90,13 @@ type CheckedEventCounts struct {
 
 // CheckedEvent is the body of the event checked.
 type CheckedEvent struct {
-	At              string              `json:"at"`
+	At              time.Time           `json:"at"`
 	Controller      string              `json:"controller,omitempty"`
 	Counts          *CheckedEventCounts `json:"counts,omitempty"`
 	IntervalSeconds int64               `json:"interval-seconds,omitempty"`
 	Probes          []ProbeVerdict      `json:"probes"`
 	Run             string              `json:"run"`
-	Started         string              `json:"started,omitempty"`
+	Started         *time.Time          `json:"started,omitempty"`
 	Took            string              `json:"took,omitempty"`
 	Unsaid          int64               `json:"unsaid,omitempty"`
 	Why             string              `json:"why,omitempty"`
diff --git a/health-and-repair/go/seats/meshwatchdogs/contract.go b/health-and-repair/go/seats/meshwatchdogs/contract.go
index 05c76ca..286d7dd 100644
--- a/health-and-repair/go/seats/meshwatchdogs/contract.go
+++ b/health-and-repair/go/seats/meshwatchdogs/contract.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strings"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -258,9 +259,9 @@ type StuckByBucketKeyValue struct {
 	Bucket string `json:"bucket"`
 	Key    string `json:"key"`
 	// it has moved again
-	Moved bool   `json:"moved,omitempty"`
-	Since string `json:"since"`
-	V     int64  `json:"v,omitempty"`
+	Moved bool      `json:"moved,omitempty"`
+	Since time.Time `json:"since"`
+	V     int64     `json:"v,omitempty"`
 	// what it waited for, in words
 	Waited string `json:"waited,omitempty"`
 }
diff --git a/identity-and-access/go/clients/meshvaultclient/client_test.go b/identity-and-access/go/clients/meshvaultclient/client_test.go
index 2c00bf5..77dba63 100644
--- a/identity-and-access/go/clients/meshvaultclient/client_test.go
+++ b/identity-and-access/go/clients/meshvaultclient/client_test.go
@@ -36,7 +36,7 @@ func TestSigningNodeLoginsAndOwnDrift(t *testing.T) {
 	}
 
 	// A node's two logins: the first, the second, a rotation to the other only, a stage only with a rotation.
-	since := "2026-11-02T01:00:00Z"
+	since := time.Date(2026, 11, 2, 1, 0, 0, 0, time.UTC)
 	for name, c := range map[string]struct {
 		l  seat.NodeLoginsByNodeValue
 		ok bool
@@ -56,7 +56,7 @@ func TestSigningNodeLoginsAndOwnDrift(t *testing.T) {
 	} else if back, err := DecodeNodeLogin(raw); err != nil || Rotates(back) {
 		t.Errorf("round trip: %+v %v", back, err)
 	}
-	if _, err := DecodeNodeLogin([]byte(`{"v":9,"node":"g14","login":"node.g14","since":"` + since + `"}`)); err == nil {
+	if _, err := DecodeNodeLogin([]byte(`{"v":9,"node":"g14","login":"node.g14","since":"` + since.Format(time.RFC3339) + `"}`)); err == nil {
 		t.Error("version 9 was taken")
 	}
 	if n, ok := LoginNode("node.g14--b"); !ok || n != "g14" {
diff --git a/identity-and-access/go/clients/meshvaultclient/signers.go b/identity-and-access/go/clients/meshvaultclient/signers.go
index 1ef79ce..476b4e6 100644
--- a/identity-and-access/go/clients/meshvaultclient/signers.go
+++ b/identity-and-access/go/clients/meshvaultclient/signers.go
@@ -87,7 +87,7 @@ func ParseCertificate(text string) (*x509.Certificate, error) {
 
 // NewSignerKey is the value of `key` for pub.
 func NewSignerKey(pub ed25519.PublicKey, made time.Time) seat.SignersByKeyValue {
-	return seat.SignersByKeyValue{V: 1, Key: base64.StdEncoding.EncodeToString(pub), Fingerprint: SignerFingerprint(pub), Made: made.UTC().Format(time.RFC3339Nano)}
+	return seat.SignersByKeyValue{V: 1, Key: base64.StdEncoding.EncodeToString(pub), Fingerprint: SignerFingerprint(pub), Made: made.UTC()}
 }
 
 // PublicKey is k's key, checked: an ed25519 public key whose fingerprint is the one k names.
diff --git a/identity-and-access/go/seats/meshnodeenroller/contract.go b/identity-and-access/go/seats/meshnodeenroller/contract.go
index 3cdab36..fc7f677 100644
--- a/identity-and-access/go/seats/meshnodeenroller/contract.go
+++ b/identity-and-access/go/seats/meshnodeenroller/contract.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strings"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -137,14 +138,14 @@ func DecodeEnrolmentsByAddressAddressValue(raw []byte) (EnrolmentsByAddressAddre
 
 // Enrolment is one open enrolment.
 type Enrolment struct {
-	Address    string `json:"address"`
-	Ask        string `json:"ask,omitempty"`
-	Caller     string `json:"caller,omitempty"`
-	Expires    string `json:"expires,omitempty"`
-	Issued     string `json:"issued,omitempty"`
-	KeysDigest string `json:"keys-digest,omitempty"`
-	Node       string `json:"node"`
-	OverlayKey string `json:"overlay-key,omitempty"`
+	Address    string     `json:"address"`
+	Ask        string     `json:"ask,omitempty"`
+	Caller     string     `json:"caller,omitempty"`
+	Expires    *time.Time `json:"expires,omitempty"`
+	Issued     *time.Time `json:"issued,omitempty"`
+	KeysDigest string     `json:"keys-digest,omitempty"`
+	Node       string     `json:"node"`
+	OverlayKey string     `json:"overlay-key,omitempty"`
 	// asked, live or redeeming
 	Stage string `json:"stage"`
 	V     int64  `json:"v,omitempty"`
@@ -266,8 +267,8 @@ type EnrolmentsByNodeNodeValue = Enrolment
 
 // EnrolmentsByAddressAddressValue is one value of the state enrolments under the key address.<address>.
 type EnrolmentsByAddressAddressValue struct {
-	Ask    string `json:"ask,omitempty"`
-	Issued string `json:"issued,omitempty"`
-	Node   string `json:"node"`
-	V      int64  `json:"v,omitempty"`
+	Ask    string     `json:"ask,omitempty"`
+	Issued *time.Time `json:"issued,omitempty"`
+	Node   string     `json:"node"`
+	V      int64      `json:"v,omitempty"`
 }
diff --git a/identity-and-access/go/seats/meshvault/contract.go b/identity-and-access/go/seats/meshvault/contract.go
index 2f3fe11..9d51257 100644
--- a/identity-and-access/go/seats/meshvault/contract.go
+++ b/identity-and-access/go/seats/meshvault/contract.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strings"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -539,18 +540,18 @@ type OwnRetiredHolderEvent struct {
 type SignersByKeyValue struct {
 	Fingerprint string `json:"fingerprint"`
 	// the signing key's public half, standard base64
-	Key  string `json:"key"`
-	Made string `json:"made"`
-	V    int64  `json:"v,omitempty"`
+	Key  string    `json:"key"`
+	Made time.Time `json:"made"`
+	V    int64     `json:"v,omitempty"`
 }
 
 // SignersByAuthorityValue is one value of the state signers under the key authority.
 type SignersByAuthorityValue struct {
 	// the authority certificate, PEM
-	Certificate string `json:"certificate"`
-	Fingerprint string `json:"fingerprint"`
-	Made        string `json:"made"`
-	V           int64  `json:"v,omitempty"`
+	Certificate string    `json:"certificate"`
+	Fingerprint string    `json:"fingerprint"`
+	Made        time.Time `json:"made"`
+	V           int64     `json:"v,omitempty"`
 }
 
 // NodeLoginsByNodeValue is one value of the state node-logins under the key <node>.
@@ -562,8 +563,8 @@ type NodeLoginsByNodeValue struct {
 	Login string `json:"login"`
 	Node  string `json:"node"`
 	// the login rotating to, empty when none
-	Rotating string `json:"rotating,omitempty"`
-	Since    string `json:"since"`
+	Rotating string    `json:"rotating,omitempty"`
+	Since    time.Time `json:"since"`
 	// begun, ready or confirmed; empty when no rotation
 	Stage string `json:"stage,omitempty"`
 	V     int64  `json:"v,omitempty"`
diff --git a/placement/go/seats/meshmoduleassigner/contract.go b/placement/go/seats/meshmoduleassigner/contract.go
index 843340f..85f9ec8 100644
--- a/placement/go/seats/meshmoduleassigner/contract.go
+++ b/placement/go/seats/meshmoduleassigner/contract.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strings"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -403,9 +404,9 @@ type Placement struct {
 
 // PlacementEventWarrant is who approved it, through which channel, when.
 type PlacementEventWarrant struct {
-	At      string `json:"at"`
-	Warrant string `json:"warrant"`
-	Words   string `json:"words"`
+	At      time.Time `json:"at"`
+	Warrant string    `json:"warrant"`
+	Words   string    `json:"words"`
 }
 
 // PlacementEvent is what each placement event carries.
@@ -421,9 +422,9 @@ type PlacementEvent struct {
 
 // Proposal is an open proposal.
 type Proposal struct {
-	Again string `json:"again,omitempty"`
-	Ask   string `json:"ask,omitempty"`
-	At    string `json:"at"`
+	Again *time.Time `json:"again,omitempty"`
+	Ask   string     `json:"ask,omitempty"`
+	At    time.Time  `json:"at"`
 	// by node whose key it changes, the revision of the key it was laid over (0: none)
 	Base         map[string]int64 `json:"base"`
 	By           string           `json:"by"`
@@ -434,14 +435,14 @@ type Proposal struct {
 	Must         []string         `json:"must,omitempty"`
 	Seed         bool             `json:"seed,omitempty"`
 	// answering, failed or asked
-	State     string   `json:"state"`
-	V         int64    `json:"v,omitempty"`
-	Verdict   *Verdict `json:"verdict,omitempty"`
-	Warrant   *Warrant `json:"warrant,omitempty"`
-	Why       string   `json:"why"`
-	Withdrawn string   `json:"withdrawn,omitempty"`
-	Words     string   `json:"words,omitempty"`
-	Written   string   `json:"written,omitempty"`
+	State     string     `json:"state"`
+	V         int64      `json:"v,omitempty"`
+	Verdict   *Verdict   `json:"verdict,omitempty"`
+	Warrant   *Warrant   `json:"warrant,omitempty"`
+	Why       string     `json:"why"`
+	Withdrawn string     `json:"withdrawn,omitempty"`
+	Words     string     `json:"words,omitempty"`
+	Written   *time.Time `json:"written,omitempty"`
 }
 
 // ProposalChangeKeys is the public halves of a joining node's keys.
@@ -507,7 +508,7 @@ type SeatHolders struct {
 type Verdict struct {
 	// every node's answer to its candidate, by node
 	Answers  map[string]map[string]any `json:"answers,omitempty"`
-	At       string                    `json:"at"`
+	At       time.Time                 `json:"at"`
 	Carried  map[string][]string       `json:"carried,omitempty"`
 	Fails    []string                  `json:"fails,omitempty"`
 	Intended map[string][]string       `json:"intended,omitempty"`
@@ -516,7 +517,7 @@ type Verdict struct {
 	// waits, pass or fail
 	State      string              `json:"state"`
 	Unintended map[string][]string `json:"unintended,omitempty"`
-	Until      string              `json:"until,omitempty"`
+	Until      *time.Time          `json:"until,omitempty"`
 }
 
 // Warrant is the enrolment's warrant an add-node carries.
diff --git a/provisioning/go/seats/meshprovisioner/contract.go b/provisioning/go/seats/meshprovisioner/contract.go
index 3d54da9..7e2325e 100644
--- a/provisioning/go/seats/meshprovisioner/contract.go
+++ b/provisioning/go/seats/meshprovisioner/contract.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strings"
+	"time"
 )
 
 // Seat is the seat's name.
@@ -217,16 +218,16 @@ type ProvisionsByNodeConsumerProvisionValueReference struct {
 
 // ProvisionsByNodeConsumerProvisionValueWarrant is a type of the contract.
 type ProvisionsByNodeConsumerProvisionValueWarrant struct {
-	Ask    string `json:"ask,omitempty"`
-	At     string `json:"at,omitempty"`
-	By     string `json:"by,omitempty"`
-	Option string `json:"option,omitempty"`
+	Ask    string     `json:"ask,omitempty"`
+	At     *time.Time `json:"at,omitempty"`
+	By     string     `json:"by,omitempty"`
+	Option string     `json:"option,omitempty"`
 }
 
 // ProvisionsByNodeConsumerProvisionValue is one value of the state provisions under the key <node>.<consumer>.<provision>.
 type ProvisionsByNodeConsumerProvisionValue struct {
 	Ask       string                                         `json:"ask,omitempty"`
-	At        string                                         `json:"at"`
+	At        time.Time                                      `json:"at"`
 	Consumer  ProvisionsByNodeConsumerProvisionValueConsumer `json:"consumer"`
 	DependsOn []string                                       `json:"depends-on,omitempty"`
 	Local     string                                         `json:"local,omitempty"`
@@ -289,16 +290,16 @@ type ProvisionsByNodeConsumerProvisionLocalValueReference struct {
 
 // ProvisionsByNodeConsumerProvisionLocalValueWarrant is a type of the contract.
 type ProvisionsByNodeConsumerProvisionLocalValueWarrant struct {
-	Ask    string `json:"ask,omitempty"`
-	At     string `json:"at,omitempty"`
-	By     string `json:"by,omitempty"`
-	Option string `json:"option,omitempty"`
+	Ask    string     `json:"ask,omitempty"`
+	At     *time.Time `json:"at,omitempty"`
+	By     string     `json:"by,omitempty"`
+	Option string     `json:"option,omitempty"`
 }
 
 // ProvisionsByNodeConsumerProvisionLocalValue is one value of the state provisions under the key <node>.<consumer>.<provision>.<local>.
 type ProvisionsByNodeConsumerProvisionLocalValue struct {
 	Ask       string                                              `json:"ask,omitempty"`
-	At        string                                              `json:"at"`
+	At        time.Time                                           `json:"at"`
 	Consumer  ProvisionsByNodeConsumerProvisionLocalValueConsumer `json:"consumer"`
 	DependsOn []string                                            `json:"depends-on,omitempty"`
 	Local     string                                              `json:"local,omitempty"`