diff --git a/arch/aeslanier/decoder.cc b/arch/aeslanier/decoder.cc
index f5d73a31..f2fcc41e 100644
--- a/arch/aeslanier/decoder.cc
+++ b/arch/aeslanier/decoder.cc
@@ -35,7 +35,7 @@ public:
 		return seekToPattern(SECTOR_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		/* Skip ID mark (we know it's a AESLANIER_RECORD_SEPARATOR). */
 
diff --git a/arch/apple2/decoder.cc b/arch/apple2/decoder.cc
index a076be63..f046e6c8 100644
--- a/arch/apple2/decoder.cc
+++ b/arch/apple2/decoder.cc
@@ -76,7 +76,7 @@ public:
 		return seekToPattern(ANY_RECORD_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		if (readRaw24() != APPLE2_SECTOR_RECORD)
 			return;
@@ -94,7 +94,7 @@ public:
 			_sector->status = Sector::DATA_MISSING; /* unintuitive but correct */
 	}
 
-    void decodeDataRecord()
+    void decodeDataRecord() override
 	{
 		/* Check ID. */
 
diff --git a/arch/brother/decoder.cc b/arch/brother/decoder.cc
index e068aa25..9fbc4072 100644
--- a/arch/brother/decoder.cc
+++ b/arch/brother/decoder.cc
@@ -64,7 +64,7 @@ public:
 		return seekToPattern(ANY_RECORD_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		if (readRaw32() != BROTHER_SECTOR_RECORD)
 			return;
@@ -86,7 +86,7 @@ public:
 		_sector->status = Sector::DATA_MISSING;
 	}
 	
-    void decodeDataRecord()
+    void decodeDataRecord() override
 	{
 		if (readRaw32() != BROTHER_DATA_RECORD)
 			return;
diff --git a/arch/c64/decoder.cc b/arch/c64/decoder.cc
index 4c0c9419..5dd3ed30 100644
--- a/arch/c64/decoder.cc
+++ b/arch/c64/decoder.cc
@@ -63,7 +63,7 @@ public:
 		return seekToPattern(ANY_RECORD_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		if (readRaw20() != C64_SECTOR_RECORD)
 			return;
@@ -79,7 +79,7 @@ public:
 			_sector->status = Sector::DATA_MISSING; /* unintuitive but correct */
 	}
 
-    void decodeDataRecord()
+    void decodeDataRecord() override
 	{
 		if (readRaw20() != C64_DATA_RECORD)
 			return;
diff --git a/arch/f85/decoder.cc b/arch/f85/decoder.cc
index 149ca9b9..96f24815 100644
--- a/arch/f85/decoder.cc
+++ b/arch/f85/decoder.cc
@@ -63,7 +63,7 @@ public:
 		return seekToPattern(ANY_RECORD_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		/* Skip sync bits and ID byte. */
 
@@ -84,7 +84,7 @@ public:
 			_sector->status = Sector::DATA_MISSING; /* unintuitive but correct */
 	}
 
-    void decodeDataRecord()
+    void decodeDataRecord() override
 	{
 		/* Skip sync bits ID byte. */
 
diff --git a/arch/fb100/decoder.cc b/arch/fb100/decoder.cc
index 46fad9ca..fd5891f9 100644
--- a/arch/fb100/decoder.cc
+++ b/arch/fb100/decoder.cc
@@ -109,7 +109,7 @@ public:
 		return seekToPattern(SECTOR_ID_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		auto rawbits = readRawBits(FB100_RECORD_SIZE*16);
 
diff --git a/arch/macintosh/decoder.cc b/arch/macintosh/decoder.cc
index ca17993f..e20c6b37 100644
--- a/arch/macintosh/decoder.cc
+++ b/arch/macintosh/decoder.cc
@@ -134,7 +134,7 @@ public:
 		return seekToPattern(ANY_RECORD_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		if (readRaw24() != MAC_SECTOR_RECORD)
 			return;
@@ -163,7 +163,7 @@ public:
 			_sector->status = Sector::DATA_MISSING; /* unintuitive but correct */
 	}
 
-    void decodeDataRecord()
+    void decodeDataRecord() override
 	{
 		if (readRaw24() != MAC_DATA_RECORD)
 			return;
@@ -183,7 +183,7 @@ public:
 		_sector->data.writer().append(userData.slice(12, 512)).append(userData.slice(0, 12));
 	}
 
-	std::set<unsigned> requiredSectors(unsigned cylinder, unsigned head) const
+	std::set<unsigned> requiredSectors(unsigned cylinder, unsigned head) const override
 	{
 		int count;
 		if (cylinder < 16)
diff --git a/arch/micropolis/decoder.cc b/arch/micropolis/decoder.cc
index 28b774c2..b9ad8146 100644
--- a/arch/micropolis/decoder.cc
+++ b/arch/micropolis/decoder.cc
@@ -106,7 +106,7 @@ public:
 		return clock;
 	}
 
-	void decodeSectorRecord()
+	void decodeSectorRecord() override
 	{
 		readRawBits(48);
 		auto rawbits = readRawBits(MICROPOLIS_ENCODED_SECTOR_SIZE*16);
diff --git a/arch/mx/decoder.cc b/arch/mx/decoder.cc
index 94de4082..670d1517 100644
--- a/arch/mx/decoder.cc
+++ b/arch/mx/decoder.cc
@@ -30,7 +30,7 @@ public:
 		AbstractDecoder(config)
 	{}
 
-    void beginTrack()
+    void beginTrack() override
 	{
 		_clock = _sector->clock = seekToPattern(ID_PATTERN);
 		_currentSector = 0;
@@ -38,7 +38,7 @@ public:
 
     nanoseconds_t advanceToNextRecord() override
 	{
-		if (_currentSector == 10)
+		if (_currentSector == 11)
 		{
 			/* That was the last sector on the disk. */
 			return 0;
@@ -47,7 +47,7 @@ public:
 			return _clock;
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		/* Skip the ID pattern and track word, which is only present on the
 		 * first sector. We don't trust the track word because some driver
diff --git a/arch/tids990/decoder.cc b/arch/tids990/decoder.cc
index c03e28e0..ebb2d2cb 100644
--- a/arch/tids990/decoder.cc
+++ b/arch/tids990/decoder.cc
@@ -52,7 +52,7 @@ public:
 		return seekToPattern(ANY_RECORD_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		auto bits = readRawBits(TIDS990_SECTOR_RECORD_SIZE*16);
 		auto bytes = decodeFmMfm(bits).slice(0, TIDS990_SECTOR_RECORD_SIZE);
@@ -74,7 +74,7 @@ public:
 			_sector->status = Sector::DATA_MISSING; /* correct but unintuitive */
 	}
 
-	void decodeDataRecord()
+	void decodeDataRecord() override
 	{
 		auto bits = readRawBits(TIDS990_DATA_RECORD_SIZE*16);
 		auto bytes = decodeFmMfm(bits).slice(0, TIDS990_DATA_RECORD_SIZE);
diff --git a/arch/victor9k/decoder.cc b/arch/victor9k/decoder.cc
index aa0df30c..50a349ea 100644
--- a/arch/victor9k/decoder.cc
+++ b/arch/victor9k/decoder.cc
@@ -64,7 +64,7 @@ public:
 		return seekToPattern(ANY_RECORD_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		/* Check the ID. */
 
@@ -89,7 +89,7 @@ public:
 			_sector->status = Sector::DATA_MISSING; /* unintuitive but correct */
 	}
 
-    void decodeDataRecord()
+    void decodeDataRecord() override
 	{
 		/* Check the ID. */
 
diff --git a/arch/zilogmcz/decoder.cc b/arch/zilogmcz/decoder.cc
index 20d01ee4..c39f0f6e 100644
--- a/arch/zilogmcz/decoder.cc
+++ b/arch/zilogmcz/decoder.cc
@@ -26,7 +26,7 @@ public:
 		return seekToPattern(SECTOR_START_PATTERN);
 	}
 
-    void decodeSectorRecord()
+    void decodeSectorRecord() override
 	{
 		readRawBits(14);
 
diff --git a/lib/logger.cc b/lib/logger.cc
index 4fceb7d5..b70e3703 100644
--- a/lib/logger.cc
+++ b/lib/logger.cc
@@ -58,17 +58,11 @@ std::string Logger::toString(const AnyLogMessage& message)
                     60e9 / m.rotationalPeriod);
             },
 
-            /* Indicates that we're starting a write operation. */
-            [&](const BeginWriteOperationLogMessage& m)
+(??)            /* Indicates that we're working on a given cylinder and head */
+(??)            [](const DiskContextLogMessage& m)
             {
-                stream << fmt::format("{:2}.{}: ", m.cylinder, m.head);
-                indented = true;
-            },
-
-            /* Indicates that we're starting a read operation. */
-            [&](const BeginReadOperationLogMessage& m)
-            {
-                stream << fmt::format("{:2}.{}: ", m.cylinder, m.head);
+(??)                std::cout << fmt::format("{:2}.{}: ", m.cylinder, m.head)
+(??)                          << std::flush;
                 indented = true;
             },