0.4.0 Release Notes

Released: 2026-03-21
Commits: 64 (since v0.3.0, 2026-03-12)
Diff: 213 files changed, 66,828 insertions, 1,242 deletions

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Highlights

This release introduces the ECL Pipeline system — a complete Extract-Conform-Load
framework spanning specification, state management, topology resolution, a pipeline
runner, source adapters, sink stages, transform stages, a CLI, and secret management.
It also includes Fabryk-side bug fixes, documentation improvements, and dependency
updates.

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New Crates (14)

ECL Pipeline Core

• ecl-pipeline-spec — Pipeline specification layer: source/stage/sink definitions,
  credential references, data stream routing (milestone 1.1)
• ecl-pipeline-state — Pipeline state types: item tracking, provenance, content
  hashing with Blake3 (milestone 1.2)
• ecl-pipeline-topo — Topology resolution: DAG construction from specs, stage
  ordering, trait definitions for adapters/stages (milestone 1.3 + 2.3)
• ecl-pipeline — Pipeline runner: execution engine, named data streams for
  multi-stream routing, crash-safe persistence via RedbStateStore
  (milestones 2.1, 2.2, 8.1)

Source Adapters

• ecl-adapter-fs — Local filesystem source adapter (milestone 3.1)
• ecl-adapter-gcs — Google Cloud Storage source adapter (milestone 7.3)
• ecl-adapter-gdrive — Google Drive source adapter with auth and content
  download (milestones 4.1, 4.2)
• ecl-adapter-sftp — SFTP source adapter with key/password auth
  (milestone 9.2)
• ecl-adapter-slack — Slack stub adapter for SourceAdapter validation
  (milestone 6.1)
• ecl-adapter-zapier — Zapier webhook push source adapter
  (milestones 7.1, 7.2)

Sink Stages

• ecl-sink-gcs — GCS sink for error/rejected item output (milestone 7.6)
• ecl-sink-kafka — Kafka sink with Avro serialization and Schema Registry
  integration (milestone 7.5)

Transform Stages

• ecl-stages — Built-in pipeline stages: CSV parsing, field mapping, validation,
  aggregation, join, batch grouping, date parsing, timezone conversion, lookup,
  decompression (ZIP/GZIP), and receipt assembly
  (milestones 3.1, 7.1, 7.2, 7.4, 8.2-8.7)

Infrastructure

• ecl-secrets — Secret management foundation for credential resolution
  (milestone 9.1)

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ECL CLI

• ecl-cli — Pipeline CLI commands: run, resume, status, inspect,
  items, diff (milestone 5.1)
• Observability and reporting: tracing spans, timing, Display impls
  (milestone 5.2)

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Fabryk Improvements

Bug Fixes

• Fix UTF-8 character boundary panic in find_snippet() full-text search
• Use floor_char_boundary to prevent panics in snippet truncation
• Add serde backward compatibility for older graph JSON formats
• Re-export ErrorCode and AnnotateAble from fabryk_mcp::model
• Migrate serde_yaml references to yaml_serde

Enhancements

• Add with_names() / with_descriptions() to all MCP tool registries
• Add shared config infrastructure to fabryk-cli
• Log service state transitions at appropriate severity levels

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Documentation

• Comprehensive Fabryk MCP server howto guide
• MCP discoverability guide iterated for better agent-driven results
• ECL pipeline redesign research and crate analysis
• Rust workflow/pipeline ecosystem survey (2026)
• ECL pipeline runner design doc (0017 v1.1) — Rust quality pass
• Phase 1-6 milestone implementation plans

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Integration Tests

• Giant Eagle end-to-end pipeline tests (Phase 2, milestone 8.8)
• Affinity end-to-end pipeline tests (Phase 1, milestone 7.8)
• File lifecycle management for GCS pipelines (milestone 7.7)
• Pipeline runner integration test suite (milestone 3.2)

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Maintenance

• Dependency updates (batch bump)
• Collapse nested if-let statements into let-chains (clippy)
• Add missing package metadata across all crates
• CI fixes: protobuf-compiler for lance-encoding, libcurl-dev for rdkafka-sys
• Upgrade actions/checkout v4 to v6 for Node.js 24 support

0.3.0 Release Notes

Highlights

This release significantly expands the fabryk-mcp-core crate with three
major additions: a composable ServerGuidance builder that unifies server
instruction generation, a ResourceRegistry trait that enables MCP resource
support (list, read, subscribe, unsubscribe), and per-URI subscription
tracking in Notifier. The DiscoverableRegistry gains a from_guidance()
constructor that eliminates repetitive wiring between guidance and registry
setup. Downstream MCP servers can now compose custom HTTP routers without
adding direct dependencies on fabryk-core or axum, thanks to new
re-exports from fabryk-mcp-core. Workspace dependency versions were also
broadly updated across crates.

Features

fabryk-mcp-core: ServerGuidance builder (guidance.rs)

A new ServerGuidance struct provides a single composable builder for all
server instruction mechanisms. It replaces scattered with_description,
with_discoverable_instructions, and with_query_strategy calls with a
declarative structure that can be shared between FabrykMcpServer and
DiscoverableRegistry.

Key capabilities:

• ServerGuidance::for_domain(domain) — creates guidance scoped to a named
  domain.
• Builder methods: .context(), .workflow(), .convention(),
  .constraint(), .subscribe(), .connector(), .data_freshness(),
  .tool_meta(), .tool_metas().
• to_instructions() — generates the ServerInfo.instructions text,
  including a directory-first directive, context, subscription
  recommendations, conventions, and constraints. Sections are omitted when
  empty.
• directory_tool_name() — returns the canonical {domain}_directory tool
  name.
• FabrykMcpServer::with_guidance(&guidance) — apply guidance to the server
  in one call.

fabryk-mcp-core: ResourceRegistry trait (resource.rs)

A new ResourceRegistry trait abstracts over MCP resource listing and
reading, allowing domains to expose subscribable resources to MCP clients.

• resources() -> Vec<Resource> — lists all available resources.
• read(uri) -> Option<ResourceFuture> — async read by URI; returns None
  for unrecognized URIs.
• FabrykMcpServer::with_resources(registry) — registers a resource registry
  and advertises resources/list, resources/read, resources/subscribe,
  and resources/unsubscribe in server capabilities.

fabryk-mcp-core: Per-URI subscription tracking in Notifier (notifier.rs)

Notifier now maintains a per-URI subscription map in addition to the
broadcast peer list.

• subscribe_resource(uri, peer) — registers a peer's interest in a specific
  URI.
• unsubscribe_resource(uri) — removes all subscriptions for a URI.
• resource_updated(uri) — if any peers have subscribed to the URI, only
  those peers are notified; otherwise all connected peers receive the
  notification (backwards-compatible broadcast).
• resource_list_changed() — broadcasts a resource-list-changed notification
  to all peers.
• Dead peers are pruned automatically on each broadcast.

fabryk-mcp-core: DiscoverableRegistry.from_guidance() (discoverable.rs)

DiscoverableRegistry gains a from_guidance(registry, &guidance)
constructor that populates all fields (tool metadata, workflow/query strategy,
connectors, subscriptions, conventions, constraints) directly from a
ServerGuidance value, removing the need to pass each field individually.

The directory tool output now includes sections for recommended subscriptions,
conventions, and constraints alongside the existing tool catalog.

fabryk-mcp-core: Re-exports of ServiceHandle, ServiceState, and axum

Downstream MCP servers can now access service lifecycle types and HTTP
composition primitives without adding direct crate dependencies:

• fabryk_mcp_core::ServiceHandle and fabryk_mcp_core::ServiceState
  (re-exported from fabryk-core).
• fabryk_mcp_core::axum (re-exported behind the http feature flag),
  enabling custom HTTP router composition.

Improvements

fabryk-mcp-core: Server resource handler integration (server.rs)

FabrykMcpServer integrates the new ResourceRegistry and subscription
infrastructure into the ServerHandler implementation. The server now
handles resources/list, resources/read, resources/subscribe, and
resources/unsubscribe protocol messages and wires subscription/
unsubscription events to the Notifier automatically.

Bug Fixes

Publish tooling: differentiated rate-limit delays for new vs existing crates

The publish Makefile target now queries the crates.io API before each
publish to determine whether a crate is new or already exists, then applies
the appropriate delay:

• Existing crates: 72 seconds (crates.io allows 1 publish per minute with
  a burst of 30, plus index propagation buffer).
• New crates: 624 seconds (crates.io allows 1 new crate per 10 minutes
  with a burst of 5, plus initial indexing buffer).

Previously a single fixed delay of 372 seconds was applied to every publish,
which was both too slow for existing crates and too fast for first-time
publishes of new crates.

Infrastructure

Workspace dependency version bumps

Cargo.toml dependency versions were updated across the following crates:
ecl-cli, ecl-steps, ecl-workflows, fabryk-acl, fabryk-auth-google,
fabryk-cli, fabryk-content, fabryk-fts, fabryk-graph,
fabryk-mcp-content, fabryk-mcp-fts, fabryk-mcp-graph,
fabryk-mcp-semantic, fabryk-mcp, fabryk-vector, and fabryk. The
Cargo.lock file was updated to reflect resolved dependency changes.

Crates Updated

Crate	Change
fabryk-mcp-core	Major feature additions (guidance, resources, subscriptions, re-exports)
fabryk-mcp	Dependency version bump
fabryk-mcp-content	Dependency version bump
fabryk-mcp-fts	Dependency version bump
fabryk-mcp-graph	Dependency version bump
fabryk-mcp-semantic	Dependency version bump
fabryk	Dependency version bump
fabryk-acl	Dependency version bump
fabryk-auth-google	Dependency version bump
fabryk-cli	Dependency version bump
fabryk-content	Dependency version bump
fabryk-fts	Dependency version bump
fabryk-graph	Dependency version bump
fabryk-vector	Dependency version bump
ecl-cli	Dependency version bump
ecl-steps	Dependency version bump
ecl-workflows	Dependency version bump

v0.2.0 Release Notes

Highlights

• Restructured crate hierarchy. Fabryk now ships two clean umbrella crates (fabryk and
  fabryk-mcp) that each re-export their constituent sub-crates. Downstream projects that
  previously depended on five or more individual crates can now express that as one or two
  [dependencies] lines. This is the most visible breaking change in this release.

• New crates. Three crates were added: fabryk-gcp for GCP credential detection,
  fabryk-mcp-semantic for deferred vector-backend wiring, and fabryk-redis for Redis
  integration and deployment utilities.

• Service lifecycle maturity. Services now support parallel startup with retry, a generic
  health router, an audit trail, and a structured async startup pattern. These foundations
  underpin the new how-to guides included in the release.

• Rust edition 2024, MSRV 1.85, and a trimmed dependency tree. Seven major dependencies
  were upgraded, three were removed, and the workspace migrated to thiserror 2 and toml 1.

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Features

New Crates

• fabryk-gcp — GCP credential detection crate. Provides helpers for locating and
  validating Google Cloud credentials at runtime, along with the log_error_chain utility
  that is now shared across the workspace. (8e998e9)

• fabryk-mcp-semantic — Adds VectorSlot, a deferred-wiring abstraction that lets an
  MCP server register a semantic-search backend without requiring the vector store to be
  available at startup time. (0d92313, 4e8cbd5)

• fabryk-redis — Redis integration crate including a deploy module and auth middleware
  updates. (16cb42a)

MCP Infrastructure

• HTTP transport — fabryk-mcp now supports Streamable HTTP transport behind an optional
  http feature flag. (80094c7)

• DiscoverableRegistry — A new registry type that exposes rich metadata to AI agents
  when they connect to an MCP server, making tool suites self-describing. (dbc1b4a,
  932b7e4)

• MCP schema validation — Input schemas are now validated on registration; previously,
  tools could be registered with an empty inputSchema, which is now caught and rejected.
  (6589bed)

• MCP diagnostics tools — Diagnostic tool handlers were added alongside the new
  fabryk-mcp-semantic crate. (4e8cbd5)

Service Lifecycle

• Parallel startup with retry — Services can now be started concurrently and monitored
  with configurable retry logic, reducing total startup time for multi-service deployments.
  (d111e63)

• Generic health router — health_router is now generic over the application state type,
  allowing it to be embedded in any Axum application without type-parameter conflicts.
  (eba8ca7)

• Audit trail — Service lifecycle events are now recorded in a structured audit trail,
  making it easier to diagnose startup and shutdown sequencing. (d111e63)

CLI

• vectordb get-model command — fabryk-cli gains a new subcommand to query the
  currently configured embedding model. Available when the vector-fastembed feature is
  enabled. (1945aa6)

Workspace Utilities (textrynum-util / textyl)

• Workspace version management — textyl can now read and write the workspace version,
  query individual crate versions, and bump versions across the workspace in one operation.
  (6da00bd)

• --project-version / --deps-version flags — textyl is no longer specific to the
  Textrynum repository and can be used against any Rust workspace. (c55f63f)

• publish-order and --exclude flags — textyl now prints the correct publish order
  for workspace crates and supports excluding crates from that list. (139bb4c)

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Improvements

Crate Hierarchy Refactor

The Fabryk workspace was restructured so that fabryk and fabryk-mcp act as umbrella
crates that re-export all sub-crates. The previous flat structure required consumers to
declare each sub-crate individually. The new layout reduces the integration surface to two
crates in the common case. (ccb078c)

Dependency Upgrades

Seven major-version dependency upgrades were applied across this release cycle:

Dependency	From	To
rmcp	1.0	1.1
toml	0.9	1.0
tantivy	0.22	0.25
fastembed	4	5
jsonwebtoken	9	10
rkyv	0.7	0.8
async-walkdir	1	2
dirs	5	6

Three previously declared dependencies were removed as unused. (561da8e, f142357)

Rust Edition and MSRV

The workspace migrated to Rust edition 2024 with a minimum supported Rust version of
1.85. thiserror was upgraded from 1 to 2 as part of this migration. (05d0e39)

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Bug Fixes

• Serialized env-var tests — Environment-variable-dependent tests in fabryk-cli were
  failing non-deterministically when run in parallel. A mutex now serializes these tests.
  (8dd9072, 74032b0)

• Reduced log_error_chain noise — log_error_chain was emitting redundant output
  when called from high-frequency paths. Logging verbosity was reduced. (74032b0)

• MCP concepts_get parameter documentation — The id parameter for concepts_get was
  described ambiguously. It is now clearly documented as a slug, obtained from the
  concepts_list results. (e4c6820)

• Internal path dependency versions — After the 0.1.0 release, internal path dependencies
  retained version = "0.1.0" while the workspace had moved to 0.1.1, causing publish
  failures. All internal versions are now kept in sync via textyl. (808e788)

• PUBLISH_ORDER in Makefile — The publish target listed crates in an order that did not
  respect dependency edges, causing cargo publish to fail on the first attempt. The order
  has been corrected. (bd4b458)

• Minor code quality issues — Three issues identified in a code audit were addressed:
  an unused import, an unneeded clone, and a redundant type annotation. (ef30512)

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Documentation

• How-to guides — Four new how-to guides were added and are linked from the workspace
  README:

  • Connecting Fabryk MCP servers to Claude Code over Streamable HTTP (dc8e37a)
  • The MCP async startup pattern for deferring expensive service initialization (ae4540a)
  • Adding a service-aware /health endpoint to an MCP server (eba8ca7)
  • Giving AI agents rich metadata via DiscoverableRegistry (932b7e4)

• How-to directory — How-to documents were moved from scattered locations into a
  dedicated docs/howtos/ directory, with a corresponding README section. (23f750d)

• Crate-level READMEs and images — README files and associated images were relocated into
  their respective crate directories to keep documentation co-located with code. (b2fe4a1)

• Architecture diagram — The workspace architecture diagram was updated to reflect the
  v0.2.0 crate restructure, along with an AI prompt for maintaining the diagram in future
  releases. (0850343, 04d1f2c)

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Infrastructure

• CI: protobuf installation — The arduino/setup-protoc GitHub Action was replaced with
  a direct apt install. The Action was hitting GitHub API rate limits in CI runs and
  producing intermittent failures. (7447adb)

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Upgrading from 0.1.x

The primary breaking change is the crate hierarchy restructure. If your project depended on
individual Fabryk sub-crates directly, update your Cargo.toml to use the umbrella crates:

# Before (0.1.x)
fabryk-core = "0.1"
fabryk-content = "0.1"
fabryk-fts = "0.1"
fabryk-graph = "0.1"
fabryk-vector = "0.1"

# After (0.2.0)
fabryk = { version = "0.2", features = ["full"] }

The fabryk-mcp umbrella follows the same pattern. Vendor-specific crates
(fabryk-auth-google, fabryk-gcp) remain separate and are versioned independently.

The Rust edition upgrade to 2024 and MSRV bump to 1.85 require Rust 1.85 or later in your
toolchain. Run rustup update stable if you are on an older toolchain.

0.1.0

Full Changelog: https://github.com/oxur/textrynum/commits/0.1.0