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mirror

mirror

github.com/goldsky-ioData & databases124.1k installsUpdated today
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About mirror

mirror is a skill for configuring and operating Goldsky Mirror streaming pipelines. It covers subgraph and direct-indexing sources, optional transformations, and delivery to databases or queues; it is especially relevant when a pipeline needs a subgraph source.

Key features

  1. 01Subgraph and dataset sources
  2. 02Optional SQL and HTTP transforms
  3. 03Database, queue, and object-storage sinks
  4. 04YAML pipeline configuration
  5. 05CLI deployment and lifecycle operations

Use cases

  1. 01Stream subgraph entities into PostgreSQL
  2. 02Filter or reshape onchain data with SQL
  3. 03Deliver records to Kafka or object storage

Install

Copy the command and run it in a terminal.

$npx skills add https://github.com/goldsky-io/goldsky-agent --skill mirror

After installing, type/mirrorin Claude Code to confirm it loaded.

Bundled filesevals/trigger-eval.json

Details

From the project README

Goldsky Mirror Pipelines

Mirror is Goldsky's original streaming pipeline product. It reads onchain data from a source (a subgraph entity or a direct-indexing dataset), optionally applies transforms, and writes the result to a sink (your database or message queue).

Mirror vs Turbo — which should you use?
MirrorTurbo
Subgraph sourcesYesNo
Speed & reliabilityGoodFaster, more reliable
Sink optionsSee common Mirror sinks belowSee the Turbo sink catalog
Config complexityModerateSimpler YAML
Dataset coverage130+ chains130+ chains, richer catalog

Use Turbo unless you need a subgraph source. Turbo is faster, more reliable, and actively gaining feature parity with Mirror — especially sink support. If you don't have a subgraph requirement, say "help me build a Turbo pipeline" and the /turbo-builder skill will guide you through a faster setup.


How Mirror Pipelines Work

Source (subgraph entity or direct-indexing dataset)
  ↓
Transforms (optional SQL or external handlers)
  ↓
Sink (PostgreSQL, ClickHouse, Kafka, S3, etc.)

A pipeline is defined in a YAML file (apiVersion: 3) and deployed with goldsky pipeline apply.


Pipeline YAML Structure

Top-level fields:

FieldTypeRequiredDescription
namestringyesLowercase letters, numbers, hyphens only. Under 50 characters.
apiVersionnumberyesAlways 3
resource_sizestringnos (default), m, l, xl, xxl
descriptionstringnoPipeline description
sourcesobjectyesAt least one source
transformsobjectnoUse {} if none needed
sinksobjectyesAt least one sink

Sources

Source typeYAML type valueDescription
Subgraph entitysubgraph_entityMirror data from Goldsky-hosted subgraphs
Dataset (direct indexing)datasetRaw onchain datasets (blocks, logs, transactions, traces, transfers)
Subgraph entity source
sources:
  subgraph_account:
    type: subgraph_entity
    name: account                # Entity name in your subgraph
    start_at: latest             # "earliest" or "latest" (default: latest)
    filter: ""                   # Optional SQL WHERE clause for fast scan
    subgraphs:
      - name: my-subgraph        # Deployed subgraph name
        version: 1.0.0
      - name: my-subgraph-arb    # Cross-chain: add more subgraphs
        version: 1.0.0

Fields: type (required: subgraph_entity), name (required: entity name), subgraphs (required: list of {name, version}), start_at (optional), filter (optional), description (optional).

Dataset source
sources:
  base_logs:
    type: dataset
    dataset_name: base.logs      # Use `goldsky dataset list --output json` to discover names
    version: 1.0.0               # Use `goldsky dataset get <name>` for versions
    start_at: latest             # "earliest" or "latest" (default: latest)
    filter: "address = '0x...'"  # Optional — enables Fast Scan for backfills

Fields: type (required: dataset), dataset_name (required), version (required), start_at (optional), filter (optional), description (optional).

Fast Scan: When filter is defined on a dataset source with start_at: earliest, the filter is pre-applied at the source level, making historical backfill much faster. Use attributes that exist in the dataset schema (goldsky dataset get <dataset_name> to check).

See docs.goldsky.com/mirror/sources/supported-sources.


Sinks

Common Mirror destinations are listed below; this is not an exhaustive count of supported sink types. Compare the specific destination the user needs, rather than inferring product-wide counts from these examples.

SinkYAML type valueNotes
PostgreSQLpostgresMost common — OLTP, auto-creates tables, upsert via INSERT ON CONFLICT. Hosted option via NeonDB.
ClickHouseclickhouseOLAP — uses ReplacingMergeTree by default, append_only_mode for best performance
MySQLmysqlOLTP workloads
ElasticsearchelasticsearchReal-time search and analytics
KafkakafkaHigh-throughput streaming to a topic, configurable topic_partitions
Object StoragefileS3, GCS, or R2 — Parquet format, append-only, supports partition_columns
AWS SQSsqsMessage queuing
WebhookwebhookHTTP POST to an external endpoint

All sinks writing to user-managed destinations require a Goldsky Secret (secret_name). Create one with goldsky secret create.

Sinks support schema_override for casting column types at the sink level (e.g., string to jsonb).

Sink examples
# PostgreSQL
sinks:
  my_pg:
    type: postgres
    table: transfers
    schema: public
    secret_name: MY_PG_SECRET
    from: my_transform

# ClickHouse
sinks:
  my_ch:
    type: clickhouse
    table: transfers
    database: my_db
    secret_name: MY_CH_SECRET
    from: my_source

# Kafka
sinks:
  my_kafka:
    type: kafka
    topic: accounts
    topic_partitions: 2
    secret_name: MY_KAFKA_SECRET
    from: my_source

# Object Storage (S3/GCS/R2)
sinks:
  my_s3:
    type: file
    path: s3://bucket/path/
    format: parquet
    secret_name: MY_S3_SECRET
    from: my_source

# SQS
sinks:
  my_sqs:
    type: sqs
    url: https://sqs.us-east-1.amazonaws.com/123456/my-queue
    secret_name: MY_SQS_SECRET
    from: my_source

See docs.goldsky.com/mirror/sinks/supported-sinks.


Transforms

TypeYAML type valueDescription
SQL(none — default)Filter, join, or reshape records with SQL
External handlerhandlerPOST records to an HTTP endpoint for custom logic
SQL transform
transforms:
  filtered_logs:
    sql: SELECT id, block_number, address FROM base_logs WHERE block_number > 1000
    primary_key: id

SQL transforms reference source or transform names as table names. Supports chaining (one transform reads from another).

Built-in decode functions:

  • _gs_log_decode(abi, topics, data) — decode raw log events
  • _gs_tx_decode(abi, input, output) — decode raw trace/transaction data
  • _gs_fetch_abi(url, type) — fetch ABI from URL (etherscan-compatible or raw JSON); fetched once at pipeline start
External handler transform
transforms:
  my_handler:
    type: handler
    primary_key: id
    url: http://example.com/transform
    from: my_source
    batch_size: 100              # Records per batch (default: 100)
    batch_flush_interval: 1s     # Flush interval (default: 1s)
    payload_columns: [col1,col2] # Optional: send subset of columns
    headers:                     # Optional custom headers
      X-Api-Key: my-key
  • At-least-once delivery with exponential backoff on failure
  • Max response time: 5 minutes; max connection time: 1 minute
  • Supports schema_override for return type casting

See docs.goldsky.com/mirror/transforms/sql-transforms.


Full YAML Examples

Subgraph entity to PostgreSQL
name: my-subgraph-sync
apiVersion: 3
resource_size: s
sources:
  subgraph_transfer:
    type: subgraph_entity
    name: Transfer
    subgraphs:
      - name: uniswap-v3
        version: 1.0.0
transforms: {}
sinks:
  my_postgres:
    type: postgres
    table: transfers
    schema: public
    secret_name: MY_PG_SECRET
    from: subgraph_transfer
Dataset (direct indexing) to PostgreSQL with SQL transform
name: base-logs-filtered
apiVersion: 3
resource_size: s
sources:
  base_logs:
    type: dataset
    dataset_name: base.logs
    version: 1.0.0
    start_at: earliest
    filter: "address = '0x833589fcd6edb6e08f4c7c32d4f71b54bda02913'"
transforms:
  select_fields:
    sql: SELECT id, block_number, transaction_hash, data FROM base_logs
    primary_key: id
sinks:
  pg_logs:
    type: postgres
    table: base_logs
    schema: public
    secret_name: MY_PG_SECRET
    from: select_fields

No subgraph source? You should almost certainly use Turbo instead — it's faster, more reliable, and has a richer dataset catalog with simpler syntax. Use /turbo-builder to get started.


CLI Reference — All Pipeline Commands

Global options available on every command: --token <string> (CLI auth token), --color (colorize output, default true), -h, --help.

goldsky pipeline apply <config-path>

Create or update a pipeline from a YAML config file. Idempotent.

FlagTypeDescription
--statusACTIVE | INACTIVE | PAUSEDDesired pipeline status
--from-snapshotstringSnapshot to start from: last, new, none, or a snapshot ID. last = latest available. new = create a fresh snapshot first. none = start from scratch. Default: new
--forcebooleanSkip confirmation prompts (useful for CI)
--skip-transform-validationbooleanSkip transform validation on update
--save-progressboolean(deprecated, use --from-snapshot) Attempt snapshot before applying
--use-latest-snapshotboolean(deprecated, use --from-snapshot) Start from latest snapshot
--skip-validationboolean(deprecated) Same as --skip-transform-validation
goldsky pipeline apply my-pipeline.yaml --status ACTIVE
goldsky pipeline apply my-pipeline.yaml --status ACTIVE --from-snapshot last
goldsky pipeline apply my-pipeline.yaml --force   # CI/CD usage
goldsky pipeline start <nameOrConfigPath>

Start a pipeline (equivalent to apply with --status ACTIVE).

FlagTypeDescription
--from-snapshotstringlast, new, none, or snapshot ID
--use-latest-snapshotboolean(deprecated, use --from-snapshot)
goldsky pipeline stop <nameOrConfigPath>

Stop a pipeline without taking a snapshot. Sets status to INACTIVE, runtime to TERMINATED.

No additional flags beyond global options.

goldsky pipeline pause <nameOrConfigPath>

Pause a pipeline with a snapshot so it can resume from where it left off. Sets status to PAUSED, runtime to TERMINATED.

No additional flags beyond global options.

goldsky pipeline restart <nameOrConfigPath>

Restart a pipeline without configuration changes. Useful when the sink database was restarted, connection is stuck, etc.

FlagTypeDescription
--from-snapshotstringRequired. last, new, none, or snapshot ID
--disable-monitoringbooleanSkip monitoring after restart (default: false)
goldsky pipeline restart my-pipeline --from-snapshot last
goldsky pipeline restart my-pipeline --from-snapshot none  # restart from scratch
goldsky pipeline get <nameOrConfigPath>

Get pipeline configuration and status.

FlagTypeDescription
--outputFormat, --outputjson | table | yamlOutput format (default: yaml)
--definitionbooleanPrint only the pipeline definition (sources, transforms, sinks)
-v, --versionstringPipeline version (default: latest)
goldsky pipeline list

List all pipelines in the project.

FlagTypeDescription
--output, --outputFormatjson | table | yamlOutput format (default: table)
--outputVerbositysummary | usablewithapplycmd | allDetail level (default: summary)
--include-runtime-detailsbooleanInclude runtime status and errors (default: false)
goldsky pipeline list --output json
goldsky pipeline list --include-runtime-details
goldsky pipeline info <nameOrConfigPath>

Display pipeline information (status, config, runtime details).

FlagTypeDescription
-v, --versionstringPipeline version (default: latest)
goldsky pipeline monitor <nameOrConfigPath>

Monitor pipeline runtime — status, metrics (records received/written), errors. Refreshes every 10 seconds.

FlagTypeDescription
--update-requestbooleanMonitor an in-flight update request
--max-refreshes, --maxRefreshesnumberMax number of data refreshes
-v, --versionstringPipeline version (default: latest)
goldsky pipeline delete <nameOrConfigPath>

Delete a pipeline permanently.

FlagTypeDescription
-f, --forcebooleanForce deletion without confirmation prompt (default: false)
goldsky pipeline resize <nameOrConfigPath> <resourceSize>

Change the compute resources for a pipeline.

PositionalDescription
resourceSizeOne of: s, m, l, xl, xxl (default: s)
goldsky pipeline resize my-pipeline l
goldsky pipeline validate [config-path]

Validate a pipeline YAML config without deploying.

FlagTypeDescription
--definitionstring(deprecated) Inline JSON definition
--definition-pathstring(deprecated) Path to JSON/YAML definition
goldsky pipeline validate my-pipeline.yaml
goldsky pipeline export [name]

Export pipeline configuration.

FlagTypeDescription
--allbooleanExport configs for all pipelines
goldsky pipeline cancel-update <nameOrConfigPath>

Cancel an in-flight update or snapshot request. Useful when a long-running snapshot blocks a needed update.

No additional flags beyond global options.

goldsky pipeline create <name> (interactive/guided)

Guided CLI experience for creating a pipeline interactively.

FlagTypeDescription
--resource-size, --resourceSizes | m | l | xl | xxlResource size (default: s)
--use-dedicated-ipbooleanUse dedicated egress IPs (default: false)
--skip-transform-validationbooleanSkip transform validation
--statusACTIVE | INACTIVE(deprecated, use pipeline start/stop/pause)
--descriptionstring(deprecated, use pipeline apply)
--definitionstring(deprecated, use pipeline apply)
--definition-pathstring(deprecated, use pipeline apply)
--output, --outputFormatjson | table | yamlOutput format (default: yaml)
goldsky pipeline get-definition <name> (deprecated)

Get a shareable pipeline definition. Use goldsky pipeline get <name> --definition instead.

Snapshot Commands
# List snapshots for a pipeline
goldsky pipeline snapshots list <nameOrConfigPath> [-v <version>]

# Create a snapshot manually
goldsky pipeline snapshots create <nameOrConfigPath>

snapshots list supports -v, --version to filter by pipeline version (default: all versions).


Lifecycle Quick Reference

ActionCommand
Deploy / startgoldsky pipeline apply <file.yaml> --status ACTIVE
Start (existing)goldsky pipeline start <name>
Pause (with snapshot)goldsky pipeline pause <name>
Stop (no snapshot)goldsky pipeline stop <name>
Restart (no config change)goldsky pipeline restart <name> --from-snapshot last
Update configgoldsky pipeline apply <file.yaml> (edit YAML first)
Resizegoldsky pipeline resize <name> <size>
Validate YAMLgoldsky pipeline validate <file.yaml>
Monitorgoldsky pipeline monitor <name>
Get configgoldsky pipeline get <name> --definition
Export configgoldsky pipeline export <name>
Deletegoldsky pipeline delete <name> -f
Cancel in-flight opgoldsky pipeline cancel-update <name>
List snapshotsgoldsky pipeline snapshots list <name>
Create snapshotgoldsky pipeline snapshots create <name>
List all pipelinesgoldsky pipeline list

Pause vs. Stop:

  • pause — takes a snapshot and suspends the pipeline (status: PAUSED + TERMINATED). Can resume from where it left off.
  • stop — stops without taking a snapshot (status: INACTIVE + TERMINATED). Resuming may reprocess data.

Desired statuses: ACTIVE, INACTIVE, PAUSED Runtime statuses: STARTING, RUNNING, FAILING, TERMINATED


Snapshots

Snapshots capture a point-in-time state of a RUNNING pipeline for resumption. They contain progress on reading sources and SQL transform state — not sink state.

  • Automatic snapshots are taken every 4 hours for healthy RUNNING pipelines.
  • Before updates: a snapshot is created automatically before applying config changes to a RUNNING pipeline.
  • On pause: a snapshot is created when pausing.
  • Manual: goldsky pipeline snapshots create <name>.
  • Resume: only the latest snapshot can be used. For older snapshots, contact support.

The --from-snapshot flag (on apply, start, restart) controls snapshot behavior:

  • new — create a fresh snapshot, then start from it (default)
  • last — use the latest existing snapshot (no new snapshot)
  • none — start from scratch, no snapshot
  • <snapshot-id> — use a specific snapshot

Resource Sizing

Set via resource_size in YAML or goldsky pipeline resize <name> <size>.

SizeDescription
sDefault. Handles most use cases, backfill of small chains, up to 300K records/sec, up to ~8 subgraph sources
m, l, xl, xxlLarger compute — for backfilling large chains or large JOINs

Start small and scale up if needed. Resource size affects pricing.


Networking

  • Mirror pipelines write data from AWS us-west-2. Ensure your sink allows inbound connections from this region.
  • IP addresses are dynamic by default.
  • Dedicated egress IPs available on request — use --use-dedicated-ip on pipeline create, or contact [email protected].
  • VPC peering available on request.
  • For external handler transforms, deploy close to us-west-2 for best performance (aim for p95 < 100ms).

Dataset Discovery

# List available datasets (non-interactive)
goldsky dataset list --output json

# Get schema for a specific dataset
goldsky dataset get <dataset_name>

Common Questions

Can Mirror pipelines use subgraphs as a source? Yes — this is Mirror's primary advantage over Turbo. Set type: subgraph_entity in your source and reference your deployed subgraph.

Can Mirror handle multiple sources or cross-chain data? Yes — define multiple sources in the YAML and use SQL transforms to join or merge them. For subgraphs, you can list multiple subgraphs (different chains) in a single source's subgraphs array.

My pipeline needs more resources / is too slow? Run goldsky pipeline resize <name> l (or xl, xxl). Start small and scale up.

My pipeline is ACTIVE but TERMINATED — what happened? The desired status is ACTIVE but the runtime failed (e.g., bad secret, sink unavailable, resource issues). Check errors with goldsky pipeline monitor <name> --include-runtime-details or view the dashboard. Fix the issue and restart.

How do I update a pipeline without losing progress? Edit your YAML and run goldsky pipeline apply <file.yaml>. By default, a snapshot is taken before the update is applied. Use --from-snapshot last to skip creating a new snapshot and use the latest existing one.

A long snapshot is blocking my update — what do I do? Run goldsky pipeline cancel-update <name> to cancel the in-flight operation, then reapply with --from-snapshot last or --from-snapshot none.


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