Case
sendspin-go -> sendspin-go
Start the server first, then the client. The server loads the PCM audio derived from almost_silent.flac, the client advertises a listener and FLAC as its only supported audio format, the server connects in, uses the SDK to encode the PCM into FLAC, streams it to the client, and the matrix compares the transported FLAC header and chunk bytes as received by the client.
Server
sendspin-go
Client
sendspin-go
Status
Passed
FLAC header and chunk bytes match exactly
Inspection
Summaries, logs, and builds
Matrix result
RAW{
"case_dir": "artifacts/results/data/macos__server-initiated-flac__sendspin-go__to__sendspin-go",
"client_exit_code": 0,
"client_impl": "sendspin-go",
"reason": "FLAC header and chunk bytes match exactly",
"scenario_id": "server-initiated-flac",
"server_exit_code": 0,
"server_impl": "sendspin-go",
"status": "passed"
}Server summary (JSON)
RAW{
"audio": {
"bit_depth": 24,
"channels": 1,
"clip_seconds": 5,
"duration_seconds": 5,
"fixture": "/Users/runner/work/conformance/conformance/repos/sendspin-cli/tests/fixtures/almost_silent.flac",
"frame_count": 40000,
"sample_rate": 8000,
"sent_audio_chunk_count": 1,
"sent_codec_header_sha256": "f7c0c5cea7e7afcc5cad7f40b3c292c811132bd60d65f8a55c383722ce6c1edb",
"sent_encoded_byte_count": 14698,
"sent_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"source_flac_sha256": "8fdda8244e318c63cd8b699fe461cd7cdddbb729327a0ba00d1bfdbe2192fe17",
"source_pcm_sha256": "f9ae8fe5e6c34fc6baa67cbb4a97224d777a0bfacf6d996449be1054824f66bf"
},
"client": {
"client_id": "sendspin-go-client-id",
"name": "sendspin-go-client",
"supported_roles": [
"player@v1"
]
},
"discovery_method": "registry_advertised",
"implementation": "sendspin-go",
"initiator_role": "server",
"peer_hello": {
"payload": {
"client_id": "sendspin-go-client-id",
"device_info": {
"manufacturer": "Sendspin Conformance",
"product_name": "sendspin-go Conformance Client",
"software_version": "0.1.0"
},
"name": "sendspin-go-client",
"player@v1_support": {
"buffer_capacity": 2000000,
"supported_commands": [
"volume",
"mute"
],
"supported_formats": [
{
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
{
"bit_depth": 24,
"channels": 1,
"codec": "pcm",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 1,
"codec": "pcm",
"sample_rate": 8000
}
]
},
"supported_roles": [
"player@v1"
],
"version": 1
},
"type": "client/hello"
},
"preferred_codec": "flac",
"role": "server",
"scenario_id": "server-initiated-flac",
"server_id": "sendspin-go-server",
"server_name": "sendspin-go server",
"status": "ok",
"stream": {
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000
}
}Server log
RAW{
"audio": {
"bit_depth": 24,
"channels": 1,
"clip_seconds": 5,
"duration_seconds": 5,
"fixture": "/Users/runner/work/conformance/conformance/repos/sendspin-cli/tests/fixtures/almost_silent.flac",
"frame_count": 40000,
"sample_rate": 8000,
"sent_audio_chunk_count": 1,
"sent_codec_header_sha256": "f7c0c5cea7e7afcc5cad7f40b3c292c811132bd60d65f8a55c383722ce6c1edb",
"sent_encoded_byte_count": 14698,
"sent_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"source_flac_sha256": "8fdda8244e318c63cd8b699fe461cd7cdddbb729327a0ba00d1bfdbe2192fe17",
"source_pcm_sha256": "f9ae8fe5e6c34fc6baa67cbb4a97224d777a0bfacf6d996449be1054824f66bf"
},
"client": {
"client_id": "sendspin-go-client-id",
"name": "sendspin-go-client",
"supported_roles": [
"player@v1"
]
},
"discovery_method": "registry_advertised",
"implementation": "sendspin-go",
"initiator_role": "server",
"peer_hello": {
"payload": {
"client_id": "sendspin-go-client-id",
"device_info": {
"manufacturer": "Sendspin Conformance",
"product_name": "sendspin-go Conformance Client",
"software_version": "0.1.0"
},
"name": "sendspin-go-client",
"player@v1_support": {
"buffer_capacity": 2000000,
"supported_commands": [
"volume",
"mute"
],
"supported_formats": [
{
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 1,
"codec": "flac",
"sample_rate": 8000
},
{
"bit_depth": 24,
"channels": 1,
"codec": "pcm",
"sample_rate": 8000
},
{
"bit_depth": 16,
"channels": 1,
"codec": "pcm",
"sample_rate": 8000
}
]
},
"supported_roles": [
"player@v1"
],
"version": 1
},
"type": "client/hello"
},
"preferred_codec": "flac",
"role": "server",
"scenario_id": "server-initiated-flac",
"server_id": "sendspin-go-server",
"server_name": "sendspin-go server",
"status": "ok",
"stream": {
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000
}
}
Client summary (JSON)
RAW{
"audio": {
"audio_chunk_count": 1,
"received_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"received_pcm_sha256": null,
"received_sample_count": 0
},
"client_id": "sendspin-go-client-id",
"client_name": "sendspin-go-client",
"implementation": "sendspin-go",
"initiator_role": "server",
"peer_hello": {
"payload": {
"active_roles": [
"player@v1"
],
"connection_reason": "playback",
"name": "sendspin-go server",
"server_id": "sendspin-go-server",
"version": 1
},
"type": "server/hello"
},
"preferred_codec": "flac",
"role": "client",
"scenario_id": "server-initiated-flac",
"server": {
"active_roles": [
"player@v1"
],
"connection_reason": "playback",
"name": "sendspin-go server",
"server_id": "sendspin-go-server",
"version": 1
},
"status": "ok",
"stream": {
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000
}
}Client log
RAW2026/05/16 05:36:31.887913 Handshake complete with server
2026/05/16 05:36:31.888753 Metadata: Sendspin Conformance - Almost Silent (Protocol Fixtures)
2026/05/16 05:36:31.888842 Group update: id=sendspin-go-server, state=playing
2026/05/16 05:36:32.017227 Read error: websocket: close 1000 (normal): done
2026/05/16 05:36:32.017506 Connection closed
{
"audio": {
"audio_chunk_count": 1,
"received_encoded_sha256": "7bc1b2ee421ee57d7ea84fee6b2a8301c83c56264081475e2c3f4ca7bd53a070",
"received_pcm_sha256": null,
"received_sample_count": 0
},
"client_id": "sendspin-go-client-id",
"client_name": "sendspin-go-client",
"implementation": "sendspin-go",
"initiator_role": "server",
"peer_hello": {
"payload": {
"active_roles": [
"player@v1"
],
"connection_reason": "playback",
"name": "sendspin-go server",
"server_id": "sendspin-go-server",
"version": 1
},
"type": "server/hello"
},
"preferred_codec": "flac",
"role": "client",
"scenario_id": "server-initiated-flac",
"server": {
"active_roles": [
"player@v1"
],
"connection_reason": "playback",
"name": "sendspin-go server",
"server_id": "sendspin-go-server",
"version": 1
},
"status": "ok",
"stream": {
"bit_depth": 24,
"channels": 1,
"codec": "flac",
"codec_header": "ZkxhQ4AAACICQAJAAAAMAADIAfQBcAAHkwCKnZ7FLvzY30lWx+3k6wJC",
"sample_rate": 8000
}
}