Release Notes — v1.13

Release date: April 2026

This release adds thread parameterization and instance aliasing, enabling a single .thread file to be reused across a weave with different parameters — turning threads into composable templates.

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Thread Templates

Define a thread config once and instantiate it multiple times in a weave with different parameters. Each instance gets a unique identity across the planner, executor, telemetry, watermark, and display.

# silver.weave
config_version: "1.0"
threads:
  - ref: silver/sap_table.thread
    as: sap_adr6
    params:
      table_name: ADR6
      schema: raw

  - ref: silver/sap_table.thread
    as: sap_adr2
    params:
      table_name: ADR2
      schema: raw

The template thread uses ${param.x} to reference injected values:

# silver/sap_table.thread
config_version: "1.0"
sources:
  sap_data:
    type: delta
    alias: ${param.schema}.${param.table_name}
steps:
  - filter:
      expr: "mandt = '100'"
target:
  alias: silver.${param.table_name}

Key features:

• as alias — overrides the thread's effective name for all downstream consumers. Required when the same ref appears multiple times in a weave.
• params dict — key-value pairs injected into the thread's parameter context under the param namespace, enabling ${param.x} references throughout the thread config.
• Two-phase resolution — expressions in param values (e.g., "${env}_silver") resolve against the parent context (weave defaults, runtime params) before injection into the thread.
• Effective name cascade — as > name > filename stem. The effective name is used in the planner DAG, executor spans, telemetry, watermark keys, and all display output.
• template_ref provenance — records the original .thread file path on each thread instance. Appears in telemetry span attributes and explain() output.
• Unused param warnings — entry params not consumed by the thread config emit telemetry warnings with source attribution, catching typos and stale config.
• Validation — duplicate refs without aliases and duplicate effective names within a weave raise ConfigError.

Instance aliasing

as works on all ThreadEntry forms — ref entries, inline definitions, and single-use refs. It simply overrides the thread's effective name, which can be useful for giving a generic template a domain-specific identity.

threads:
  # Single-use ref with cosmetic rename
  - ref: shared/customer_load.thread
    as: dim_customer

  # Inline thread with alias
  - name: raw_loader
    as: staging_loader
    config_version: "1.0"
    sources: ...
    target: ...

Backwards compatibility

Existing configs without as or params work identically. The new fields are fully optional and default to null.

See the Thread Templates guide for full documentation.

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Also in this release

• Documentation drift fixes across 15 pages (JSON log field names, API paths, types, version stamps, missing schema entries)
• weevr-cli cross-references added to README and docs home page