diff --git a/internal/dhcpd/dhcpd_test.go b/internal/dhcpd/dhcpd_test.go
index f65e6823..f5c34154 100644
--- a/internal/dhcpd/dhcpd_test.go
+++ b/internal/dhcpd/dhcpd_test.go
@@ -45,12 +45,17 @@ func TestDB(t *testing.T) {
 	l.HWAddr, _ = net.ParseMAC("aa:aa:aa:aa:aa:aa")
 	exp1 := time.Now().Add(time.Hour)
 	l.Expiry = exp1
-	s.srv4.(*v4Server).addLease(&l)
+
+	srv4, ok := s.srv4.(*v4Server)
+	assert.True(t, ok)
+
+	srv4.addLease(&l)
 
 	l2 := Lease{}
 	l2.IP = net.IP{192, 168, 10, 101}
 	l2.HWAddr, _ = net.ParseMAC("aa:aa:aa:aa:aa:bb")
-	s.srv4.AddStaticLease(l2)
+	err = s.srv4.AddStaticLease(l2)
+	assert.Nil(t, err)
 
 	_ = os.Remove("leases.db")
 	s.dbStore()
diff --git a/internal/dhcpd/v4_test.go b/internal/dhcpd/v4_test.go
index 74eab484..8edb3113 100644
--- a/internal/dhcpd/v4_test.go
+++ b/internal/dhcpd/v4_test.go
@@ -69,7 +69,8 @@ func TestV4StaticLeaseAddReplaceDynamic(t *testing.T) {
 		notify:     notify4,
 	}
 	sIface, err := v4Create(conf)
-	s := sIface.(*v4Server)
+	s, ok := sIface.(*v4Server)
+	assert.True(t, ok)
 	assert.Nil(t, err)
 
 	// add dynamic lease
@@ -121,7 +122,8 @@ func TestV4StaticLeaseGet(t *testing.T) {
 		notify:     notify4,
 	}
 	sIface, err := v4Create(conf)
-	s := sIface.(*v4Server)
+	s, ok := sIface.(*v4Server)
+	assert.True(t, ok)
 	assert.Nil(t, err)
 	s.conf.dnsIPAddrs = []net.IP{{192, 168, 10, 1}}
 
@@ -184,7 +186,8 @@ func TestV4DynamicLeaseGet(t *testing.T) {
 		},
 	}
 	sIface, err := v4Create(conf)
-	s := sIface.(*v4Server)
+	s, ok := sIface.(*v4Server)
+	assert.True(t, ok)
 	assert.Nil(t, err)
 	s.conf.dnsIPAddrs = []net.IP{{192, 168, 10, 1}}
 
diff --git a/internal/dhcpd/v6_test.go b/internal/dhcpd/v6_test.go
index 1c54163a..9cdf3ee4 100644
--- a/internal/dhcpd/v6_test.go
+++ b/internal/dhcpd/v6_test.go
@@ -64,7 +64,8 @@ func TestV6StaticLeaseAddReplaceDynamic(t *testing.T) {
 		notify:     notify6,
 	}
 	sIface, err := v6Create(conf)
-	s := sIface.(*v6Server)
+	s, ok := sIface.(*v6Server)
+	assert.True(t, ok)
 	assert.Nil(t, err)
 
 	// add dynamic lease
@@ -113,7 +114,8 @@ func TestV6GetLease(t *testing.T) {
 		notify:     notify6,
 	}
 	sIface, err := v6Create(conf)
-	s := sIface.(*v6Server)
+	s, ok := sIface.(*v6Server)
+	assert.True(t, ok)
 	assert.Nil(t, err)
 	s.conf.dnsIPAddrs = []net.IP{net.ParseIP("2000::1")}
 	s.sid = dhcpv6.Duid{
@@ -173,7 +175,8 @@ func TestV6GetDynamicLease(t *testing.T) {
 		notify:     notify6,
 	}
 	sIface, err := v6Create(conf)
-	s := sIface.(*v6Server)
+	s, ok := sIface.(*v6Server)
+	assert.True(t, ok)
 	assert.Nil(t, err)
 	s.conf.dnsIPAddrs = []net.IP{net.ParseIP("2000::1")}
 	s.sid = dhcpv6.Duid{
diff --git a/internal/dnsfilter/dnsfilter_test.go b/internal/dnsfilter/dnsfilter_test.go
index 257953ad..6ab4fbc4 100644
--- a/internal/dnsfilter/dnsfilter_test.go
+++ b/internal/dnsfilter/dnsfilter_test.go
@@ -683,7 +683,10 @@ func TestWhitelist(t *testing.T) {
 		ID: 0, Data: []byte(whiteRules),
 	}}
 	d := newForTest(nil, filters)
-	d.SetFilters(filters, whiteFilters, false)
+
+	err := d.SetFilters(filters, whiteFilters, false)
+	assert.Nil(t, err)
+
 	t.Cleanup(d.Close)
 
 	// Matched by white filter.
diff --git a/internal/dnsforward/dnsforward_test.go b/internal/dnsforward/dnsforward_test.go
index 86356c6b..9b72dd52 100644
--- a/internal/dnsforward/dnsforward_test.go
+++ b/internal/dnsforward/dnsforward_test.go
@@ -1113,8 +1113,10 @@ func TestPTRResponseFromDHCPLeases(t *testing.T) {
 	assert.Equal(t, dns.TypePTR, resp.Answer[0].Header().Rrtype)
 	assert.Equal(t, "1.0.0.127.in-addr.arpa.", resp.Answer[0].Header().Name)
 
-	ptr := resp.Answer[0].(*dns.PTR)
-	assert.Equal(t, "localhost.", ptr.Ptr)
+	ptr, ok := resp.Answer[0].(*dns.PTR)
+	if assert.True(t, ok) {
+		assert.Equal(t, "localhost.", ptr.Ptr)
+	}
 
 	s.Close()
 }
@@ -1158,8 +1160,10 @@ func TestPTRResponseFromHosts(t *testing.T) {
 	assert.Equal(t, dns.TypePTR, resp.Answer[0].Header().Rrtype)
 	assert.Equal(t, "1.0.0.127.in-addr.arpa.", resp.Answer[0].Header().Name)
 
-	ptr := resp.Answer[0].(*dns.PTR)
-	assert.Equal(t, "host.", ptr.Ptr)
+	ptr, ok := resp.Answer[0].(*dns.PTR)
+	if assert.True(t, ok) {
+		assert.Equal(t, "host.", ptr.Ptr)
+	}
 
 	s.Close()
 }
diff --git a/internal/dnsforward/dnsrewrite_test.go b/internal/dnsforward/dnsrewrite_test.go
index b3f5ecf3..4029038a 100644
--- a/internal/dnsforward/dnsrewrite_test.go
+++ b/internal/dnsforward/dnsrewrite_test.go
@@ -130,9 +130,11 @@ func TestServer_FilterDNSRewrite(t *testing.T) {
 		assert.Nil(t, err)
 		assert.Equal(t, dns.RcodeSuccess, d.Res.Rcode)
 		if assert.Len(t, d.Res.Answer, 1) {
-			ans := d.Res.Answer[0].(*dns.MX)
-			assert.Equal(t, mx.Exchange, ans.Mx)
-			assert.Equal(t, mx.Preference, ans.Preference)
+			ans, ok := d.Res.Answer[0].(*dns.MX)
+			if assert.True(t, ok) {
+				assert.Equal(t, mx.Exchange, ans.Mx)
+				assert.Equal(t, mx.Preference, ans.Preference)
+			}
 		}
 	})
 
@@ -145,11 +147,13 @@ func TestServer_FilterDNSRewrite(t *testing.T) {
 		assert.Nil(t, err)
 		assert.Equal(t, dns.RcodeSuccess, d.Res.Rcode)
 		if assert.Len(t, d.Res.Answer, 1) {
-			ans := d.Res.Answer[0].(*dns.SVCB)
-			assert.Equal(t, dns.SVCB_ALPN, ans.Value[0].Key())
-			assert.Equal(t, svcb.Params["alpn"], ans.Value[0].String())
-			assert.Equal(t, svcb.Target, ans.Target)
-			assert.Equal(t, svcb.Priority, ans.Priority)
+			ans, ok := d.Res.Answer[0].(*dns.SVCB)
+			if assert.True(t, ok) {
+				assert.Equal(t, dns.SVCB_ALPN, ans.Value[0].Key())
+				assert.Equal(t, svcb.Params["alpn"], ans.Value[0].String())
+				assert.Equal(t, svcb.Target, ans.Target)
+				assert.Equal(t, svcb.Priority, ans.Priority)
+			}
 		}
 	})
 
@@ -162,11 +166,13 @@ func TestServer_FilterDNSRewrite(t *testing.T) {
 		assert.Nil(t, err)
 		assert.Equal(t, dns.RcodeSuccess, d.Res.Rcode)
 		if assert.Len(t, d.Res.Answer, 1) {
-			ans := d.Res.Answer[0].(*dns.HTTPS)
-			assert.Equal(t, dns.SVCB_ALPN, ans.Value[0].Key())
-			assert.Equal(t, svcb.Params["alpn"], ans.Value[0].String())
-			assert.Equal(t, svcb.Target, ans.Target)
-			assert.Equal(t, svcb.Priority, ans.Priority)
+			ans, ok := d.Res.Answer[0].(*dns.HTTPS)
+			if assert.True(t, ok) {
+				assert.Equal(t, dns.SVCB_ALPN, ans.Value[0].Key())
+				assert.Equal(t, svcb.Params["alpn"], ans.Value[0].String())
+				assert.Equal(t, svcb.Target, ans.Target)
+				assert.Equal(t, svcb.Priority, ans.Priority)
+			}
 		}
 	})
 }
diff --git a/internal/home/auth_test.go b/internal/home/auth_test.go
index 4a4a21c8..e44b7e83 100644
--- a/internal/home/auth_test.go
+++ b/internal/home/auth_test.go
@@ -79,7 +79,6 @@ func TestAuth(t *testing.T) {
 	assert.Equal(t, checkSessionNotFound, a.checkSession(sessStr))
 
 	a.Close()
-	os.Remove(fn)
 }
 
 // implements http.ResponseWriter
diff --git a/internal/home/middlewares_test.go b/internal/home/middlewares_test.go
index 4d6a33d0..53b7a933 100644
--- a/internal/home/middlewares_test.go
+++ b/internal/home/middlewares_test.go
@@ -42,7 +42,10 @@ func TestLimitRequestBody(t *testing.T) {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			var b []byte
 			b, *err = ioutil.ReadAll(r.Body)
-			w.Write(b)
+			_, werr := w.Write(b)
+			if werr != nil {
+				panic(werr)
+			}
 		})
 	}
 
diff --git a/internal/stats/stats_test.go b/internal/stats/stats_test.go
index c4fbe191..06163c6c 100644
--- a/internal/stats/stats_test.go
+++ b/internal/stats/stats_test.go
@@ -34,6 +34,10 @@ func TestStats(t *testing.T) {
 		Filename:  "./stats.db",
 		LimitDays: 1,
 	}
+	t.Cleanup(func() {
+		assert.Nil(t, os.Remove(conf.Filename))
+	})
+
 	s, _ := createObject(conf)
 
 	e := Entry{}
@@ -86,7 +90,6 @@ func TestStats(t *testing.T) {
 
 	s.clear()
 	s.Close()
-	os.Remove(conf.Filename)
 }
 
 func TestLargeNumbers(t *testing.T) {
@@ -102,7 +105,10 @@ func TestLargeNumbers(t *testing.T) {
 		LimitDays: 1,
 		UnitID:    newID,
 	}
-	os.Remove(conf.Filename)
+	t.Cleanup(func() {
+		assert.Nil(t, os.Remove(conf.Filename))
+	})
+
 	s, _ := createObject(conf)
 	e := Entry{}
 
@@ -128,7 +134,6 @@ func TestLargeNumbers(t *testing.T) {
 	assert.EqualValues(t, int(hour)*n, d.NumDNSQueries)
 
 	s.Close()
-	os.Remove(conf.Filename)
 }
 
 // this code is a chunk copied from getData() that generates aggregate data per day
diff --git a/scripts/make/go-lint.sh b/scripts/make/go-lint.sh
index 59c4cbf1..e1aeb9ef 100644
--- a/scripts/make/go-lint.sh
+++ b/scripts/make/go-lint.sh
@@ -140,7 +140,8 @@ ineffassign .
 
 unparam ./...
 
-git ls-files -- '*.go' '*.md' '*.yaml' '*.yml' 'Makefile'\
+git ls-files -- '*.go' '*.md' '*.mod' '*.sh' '*.yaml' '*.yml'\
+	'Makefile'\
 	| xargs misspell --error
 
 looppointer ./...
@@ -157,7 +158,7 @@ nilness ./...
 # errcheck ./...
 exit_on_output sh -c '
 	errcheck --asserts --ignoregenerated ./... |\
-		{ grep -e "defer" -e "_test\.go:" -v || exit 0; }
+		{ grep -e "defer" -v || exit 0; }
 '
 
 staticcheck ./...