diff --git a/storage/sealing/fsm.go b/storage/sealing/fsm.go
index bd3031aca..89d27178c 100644
--- a/storage/sealing/fsm.go
+++ b/storage/sealing/fsm.go
@@ -2,6 +2,7 @@ package sealing
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"reflect"
 	"time"
@@ -82,10 +83,17 @@ func (m *Sealing) plan(events []statemachine.Event, state *SectorInfo) (func(sta
 	/////
 	// First process all events
 
+
 	for _, event := range events {
+		e, err := json.Marshal(event)
+		if err != nil {
+			log.Errorf("marshaling event for logging: %+v", err)
+			continue
+		}
+
 		l := Log{
 			Timestamp: uint64(time.Now().Unix()),
-			Message:   fmt.Sprintf("%s", event),
+			Message:   string(e),
 			Kind:      fmt.Sprintf("event;%T", event.User),
 		}
 
@@ -201,7 +209,7 @@ func planCommitting(events []statemachine.Event, state *SectorInfo) error {
 			e.apply(state)
 			state.State = api.CommitWait
 		case SectorSeedReady: // seed changed :/
-			if e.seed.Equals(&state.Seed) {
+			if e.Seed.Equals(&state.Seed) {
 				log.Warnf("planCommitting: got SectorSeedReady, but the seed didn't change")
 				continue // or it didn't!
 			}
diff --git a/storage/sealing/fsm_events.go b/storage/sealing/fsm_events.go
index e809685eb..d358ba360 100644
--- a/storage/sealing/fsm_events.go
+++ b/storage/sealing/fsm_events.go
@@ -3,6 +3,7 @@ package sealing
 import (
 	"github.com/filecoin-project/specs-actors/actors/abi"
 	"github.com/ipfs/go-cid"
+	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/lotus/api"
 )
@@ -25,6 +26,7 @@ type SectorRestart struct{}
 func (evt SectorRestart) applyGlobal(*SectorInfo) bool { return false }
 
 type SectorFatalError struct{ error }
+func (evt SectorFatalError) FormatError(xerrors.Printer) (next error) {return evt.error}
 
 func (evt SectorFatalError) applyGlobal(state *SectorInfo) bool {
 	log.Errorf("Fatal error on sector %d: %+v", state.SectorID, evt.error)
@@ -35,32 +37,32 @@ func (evt SectorFatalError) applyGlobal(state *SectorInfo) bool {
 }
 
 type SectorForceState struct {
-	state api.SectorState
+	State api.SectorState
 }
 
 func (evt SectorForceState) applyGlobal(state *SectorInfo) bool {
-	state.State = evt.state
+	state.State = evt.State
 	return true
 }
 
 // Normal path
 
 type SectorStart struct {
-	id         abi.SectorNumber
-	sectorType abi.RegisteredProof
-	pieces     []Piece
+	ID         abi.SectorNumber
+	SectorType abi.RegisteredProof
+	Pieces     []Piece
 }
 
 func (evt SectorStart) apply(state *SectorInfo) {
-	state.SectorID = evt.id
-	state.Pieces = evt.pieces
-	state.SectorType = evt.sectorType
+	state.SectorID = evt.ID
+	state.Pieces = evt.Pieces
+	state.SectorType = evt.SectorType
 }
 
-type SectorPacked struct{ pieces []Piece }
+type SectorPacked struct{ Pieces []Piece }
 
 func (evt SectorPacked) apply(state *SectorInfo) {
-	state.Pieces = append(state.Pieces, evt.pieces...)
+	state.Pieces = append(state.Pieces, evt.Pieces...)
 }
 
 type SectorPackingFailed struct{ error }
@@ -68,57 +70,59 @@ type SectorPackingFailed struct{ error }
 func (evt SectorPackingFailed) apply(*SectorInfo) {}
 
 type SectorSealed struct {
-	commR  cid.Cid
-	commD  cid.Cid
-	ticket api.SealTicket
+	Sealed   cid.Cid
+	Unsealed cid.Cid
+	Ticket   api.SealTicket
 }
 
 func (evt SectorSealed) apply(state *SectorInfo) {
-	commd := evt.commD
+	commd := evt.Unsealed
 	state.CommD = &commd
-	commr := evt.commR
+	commr := evt.Sealed
 	state.CommR = &commr
-	state.Ticket = evt.ticket
+	state.Ticket = evt.Ticket
 }
 
 type SectorSealFailed struct{ error }
-
+func (evt SectorSealFailed) FormatError(xerrors.Printer) (next error) {return evt.error}
 func (evt SectorSealFailed) apply(*SectorInfo) {}
 
 type SectorPreCommitFailed struct{ error }
-
+func (evt SectorPreCommitFailed) FormatError(xerrors.Printer) (next error) {return evt.error}
 func (evt SectorPreCommitFailed) apply(*SectorInfo) {}
 
 type SectorPreCommitted struct {
-	message cid.Cid
+	Message cid.Cid
 }
 
 func (evt SectorPreCommitted) apply(state *SectorInfo) {
-	state.PreCommitMessage = &evt.message
+	state.PreCommitMessage = &evt.Message
 }
 
 type SectorSeedReady struct {
-	seed api.SealSeed
+	Seed api.SealSeed
 }
 
 func (evt SectorSeedReady) apply(state *SectorInfo) {
-	state.Seed = evt.seed
+	state.Seed = evt.Seed
 }
 
 type SectorComputeProofFailed struct{ error }
+func (evt SectorComputeProofFailed) FormatError(xerrors.Printer) (next error) {return evt.error}
+func (evt SectorComputeProofFailed) apply(*SectorInfo) {}
 
 type SectorCommitFailed struct{ error }
-
+func (evt SectorCommitFailed) FormatError(xerrors.Printer) (next error) {return evt.error}
 func (evt SectorCommitFailed) apply(*SectorInfo) {}
 
 type SectorCommitted struct {
-	message cid.Cid
-	proof   []byte
+	Message cid.Cid
+	Proof   []byte
 }
 
 func (evt SectorCommitted) apply(state *SectorInfo) {
-	state.Proof = evt.proof
-	state.CommitMessage = &evt.message
+	state.Proof = evt.Proof
+	state.CommitMessage = &evt.Message
 }
 
 type SectorProving struct{}
@@ -130,7 +134,7 @@ type SectorFinalized struct{}
 func (evt SectorFinalized) apply(*SectorInfo) {}
 
 type SectorFinalizeFailed struct{ error }
-
+func (evt SectorFinalizeFailed) FormatError(xerrors.Printer) (next error) {return evt.error}
 func (evt SectorFinalizeFailed) apply(*SectorInfo) {}
 
 // Failed state recovery
diff --git a/storage/sealing/fsm_test.go b/storage/sealing/fsm_test.go
index 41becc4f3..9b1a5d3e8 100644
--- a/storage/sealing/fsm_test.go
+++ b/storage/sealing/fsm_test.go
@@ -76,12 +76,12 @@ func TestSeedRevert(t *testing.T) {
 	m.planSingle(SectorSeedReady{})
 	require.Equal(m.t, m.state.State, api.Committing)
 
-	_, err := m.s.plan([]statemachine.Event{{SectorSeedReady{seed: api.SealSeed{Epoch: 5}}}, {SectorCommitted{}}}, m.state)
+	_, err := m.s.plan([]statemachine.Event{{SectorSeedReady{Seed: api.SealSeed{Epoch: 5}}}, {SectorCommitted{}}}, m.state)
 	require.NoError(t, err)
 	require.Equal(m.t, m.state.State, api.Committing)
 
 	// not changing the seed this time
-	_, err = m.s.plan([]statemachine.Event{{SectorSeedReady{seed: api.SealSeed{Epoch: 5}}}, {SectorCommitted{}}}, m.state)
+	_, err = m.s.plan([]statemachine.Event{{SectorSeedReady{Seed: api.SealSeed{Epoch: 5}}}, {SectorCommitted{}}}, m.state)
 	require.Equal(m.t, m.state.State, api.CommitWait)
 
 	m.planSingle(SectorProving{})
diff --git a/storage/sealing/sealing.go b/storage/sealing/sealing.go
index 3c50a1507..bcfdab3b2 100644
--- a/storage/sealing/sealing.go
+++ b/storage/sealing/sealing.go
@@ -150,9 +150,9 @@ func (m *Sealing) SealPiece(ctx context.Context, size abi.UnpaddedPieceSize, r i
 func (m *Sealing) newSector(sid abi.SectorNumber, rt abi.RegisteredProof, pieces []Piece) error {
 	log.Infof("Start sealing %d", sid)
 	return m.sectors.Send(uint64(sid), SectorStart{
-		id:         sid,
-		pieces:     pieces,
-		sectorType: rt,
+		ID:         sid,
+		Pieces:     pieces,
+		SectorType: rt,
 	})
 }
 
diff --git a/storage/sealing/states.go b/storage/sealing/states.go
index 24f44fdf0..3e6037b6d 100644
--- a/storage/sealing/states.go
+++ b/storage/sealing/states.go
@@ -46,7 +46,7 @@ func (m *Sealing) handlePacking(ctx statemachine.Context, sector SectorInfo) err
 		return xerrors.Errorf("filling up the sector (%v): %w", fillerSizes, err)
 	}
 
-	return ctx.Send(SectorPacked{pieces: pieces})
+	return ctx.Send(SectorPacked{Pieces: pieces})
 }
 
 func (m *Sealing) handleUnsealed(ctx statemachine.Context, sector SectorInfo) error {
@@ -81,9 +81,9 @@ func (m *Sealing) handleUnsealed(ctx statemachine.Context, sector SectorInfo) er
 	}
 
 	return ctx.Send(SectorSealed{
-		commD:  cids.Unsealed,
-		commR:  cids.Sealed,
-		ticket: *ticket,
+		Unsealed: cids.Unsealed,
+		Sealed:   cids.Sealed,
+		Ticket:   *ticket,
 	})
 }
 
@@ -132,7 +132,7 @@ func (m *Sealing) handlePreCommitting(ctx statemachine.Context, sector SectorInf
 		return ctx.Send(SectorPreCommitFailed{xerrors.Errorf("pushing message to mpool: %w", err)})
 	}
 
-	return ctx.Send(SectorPreCommitted{message: smsg.Cid()})
+	return ctx.Send(SectorPreCommitted{Message: smsg.Cid()})
 }
 
 func (m *Sealing) handleWaitSeed(ctx statemachine.Context, sector SectorInfo) error {
@@ -162,7 +162,7 @@ func (m *Sealing) handleWaitSeed(ctx statemachine.Context, sector SectorInfo) er
 			return err
 		}
 
-		ctx.Send(SectorSeedReady{seed: api.SealSeed{
+		ctx.Send(SectorSeedReady{Seed: api.SealSeed{
 			Epoch: randHeight,
 			Value: abi.InteractiveSealRandomness(rand),
 		}})
@@ -229,8 +229,8 @@ func (m *Sealing) handleCommitting(ctx statemachine.Context, sector SectorInfo)
 	}
 
 	return ctx.Send(SectorCommitted{
-		proof:   proof,
-		message: smsg.Cid(),
+		Proof:   proof,
+		Message: smsg.Cid(),
 	})
 }