diff --git a/Dockerfile b/Dockerfile
index 038a547..2dea10c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -12,6 +12,4 @@ FROM scratch
 COPY --from=builder /checker-alias /checker-alias
 USER 65534:65534
 EXPOSE 8080
-HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
-  CMD ["/checker-alias", "-healthcheck"]
 ENTRYPOINT ["/checker-alias"]
diff --git a/checker/collect.go b/checker/collect.go
index 426dbc4..cd894be 100644
--- a/checker/collect.go
+++ b/checker/collect.go
@@ -215,7 +215,7 @@ func (c *chainCtx) reanchor(ctx context.Context, name string) (string, []string,
 	return zone, ns, nil
 }
 
-// isReferral detects "NOERROR + no Answer for owner + NS in Authority": the
+// isReferral detects "NOERROR + no Answer for owner + NS in Authority" — the
 // shape of a delegation response from a parent auth.
 func isReferral(r *dns.Msg, owner string) bool {
 	if r == nil || r.Rcode != dns.RcodeSuccess || len(r.Answer) > 0 {
diff --git a/checker/rules_common.go b/checker/rules_common.go
index b267fba..8415eaf 100644
--- a/checker/rules_common.go
+++ b/checker/rules_common.go
@@ -16,7 +16,7 @@ const (
 	defaultRecognizeApexFlattening = true
 
 	// hintKey is the CheckState.Meta key the HTML report reads to render the
-	// "How to fix" block: keep them in sync.
+	// "How to fix" block — keep them in sync.
 	hintKey = "hint"
 )
 
@@ -31,7 +31,7 @@ func loadAlias(ctx context.Context, obs sdk.ObservationGetter) (*AliasData, []sd
 	return &data, nil
 }
 
-// skipped is the "nothing to judge right now" return: rules must produce at
+// skipped is the "nothing to judge right now" return — rules must produce at
 // least one state, otherwise the SDK substitutes StatusUnknown.
 func skipped(reason string) []sdk.CheckState {
 	return []sdk.CheckState{{
diff --git a/checker/types.go b/checker/types.go
index 724ec27..4d7a6a6 100644
--- a/checker/types.go
+++ b/checker/types.go
@@ -61,7 +61,7 @@ type AliasData struct {
 	Chain           []ChainHop       `json:"chain,omitempty"`
 	ChainTerminated ChainTermination `json:"chain_terminated"`
 
-	// FinalTarget is the last name in the chain, equal to Owner when there is
+	// FinalTarget is the last name in the chain — equal to Owner when there is
 	// no indirection.
 	FinalTarget string   `json:"final_target,omitempty"`
 	FinalA      []string `json:"final_a,omitempty"`
diff --git a/go.mod b/go.mod
index 4e885c2..c0bd4cd 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,7 @@ module git.happydns.org/checker-alias
 go 1.25.0
 
 require (
-	git.happydns.org/checker-sdk-go v1.5.0
+	git.happydns.org/checker-sdk-go v1.4.0
 	github.com/miekg/dns v1.1.72
 )
 
diff --git a/go.sum b/go.sum
index 2a80023..fc3939b 100644
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,5 @@
-git.happydns.org/checker-sdk-go v1.5.0 h1:5uD5Cm6xJ+lwnhbJ09iCXGHbYS9zRh+Yh0NeBHkAPBY=
-git.happydns.org/checker-sdk-go v1.5.0/go.mod h1:aNAcfYFfbhvH9kJhE0Njp5GX0dQbxdRB0rJ0KvSC5nI=
+git.happydns.org/checker-sdk-go v1.4.0 h1:sO8EnF3suhNgYLRsbmCZWJOymH/oNMrOUqj3FEzJArs=
+git.happydns.org/checker-sdk-go v1.4.0/go.mod h1:aNAcfYFfbhvH9kJhE0Njp5GX0dQbxdRB0rJ0KvSC5nI=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/miekg/dns v1.1.72 h1:vhmr+TF2A3tuoGNkLDFK9zi36F2LS+hKTRW0Uf8kbzI=