v0.2

Released August 2026 · Current preview: v0.2.1

v0.2 expands tapstate's authoring and runtime surfaces while remaining a non-production preview. It adds document assembly with nest, discovered schema validation, and connected CLI operations. See the GitHub releases for native CLI bundles, checksums, and release assets.

What changed

v0.2.1

• The local playground creates and discovers the MySQL source before it applies the pipeline that reads its rows. This allows the reference MySQL-to-MongoDB flow to complete its initial snapshot instead of failing before the pipeline is created.
• tapstate --version reports tapstate 0.2.1, and the CLI installer defaults to this release.
• The disposable local playground downloads the 0.2.1 CLI and uses the pinned ghcr.io/tapstate/tapstate:0.2.1 server image.
• Declare a view as the complete instruction to materialize rows into the managed state store. serve.sync remains the separate path for delivery to an external system, and a pipeline can use either or both.

v0.2.0

• Use nest transforms to assemble related streams into documents, including explicit root and child key-change tracking when the source supplies before images.
• Catch incompatible CEL row expressions at apply time using discovered source schemas, with separate diagnostics for missing, unsupported, and unknown types. See row-expression schema and type errors.
• Use command-level CLI help and authenticated connected commands in addition to the interactive REPL.
• Run the local MCP gateway from the complete CLI bundle to expose supported control-plane operations to an MCP host.
• Write MySQL TIMESTAMP(3) values as MongoDB BSON dates at millisecond precision on the verified MySQL-to-MongoDB path. The instant is preserved; the source time-zone or offset representation is not. See the data compatibility notes for MySQL and MongoDB.

Release components

The local playground uses the pinned ghcr.io/tapstate/tapstate:0.2.1 server image and the separate MySQL and MongoDB connector preview assets. The server image and connector artifacts support the disposable reference path; they are not a production deployment method or a general connector support contract.

The CLI release contains macOS and glibc-based Linux bundles for arm64 and x64. Each archive has a SHA-256 file, and checksums.txt covers all four. Recommended minimums for this build are macOS 15.0 and glibc 2.34.

Known limitations

• The runtime is single-node, keeps runtime state in memory, and is not intended for production.
• The v0.2 local playground verifies one end-to-end combination: MySQL initial load plus CDC, an in-flight map, and MongoDB materialization.
• A change that a connector reads is delivered at least once, not exactly once.
• An insert-only target can receive duplicate rows when the snapshot and CDC reads overlap and both observe the same row.
• A source change written while the change stream is positioning itself can be missed before the connector reads it, because the saved position is not passed to the stream read until the snapshot finishes. The at-least-once statement does not cover a change that the connector never reads.
• Runtime connector registration accepts only the published MySQL and MongoDB preview artifacts. An artifact declaring another connector ID is refused with connector.not-official; catalog metadata does not expand this boundary.
• join remains declared by the Schema but is refused by the current runtime.
• run, export, diff, and edit remain reserved CLI verbs and return exit code 3.
• The server-backed preview is provided through the disposable Docker playground; this release does not include a standalone server installer or operator deployment guide. See Install the CLI for the CLI/server boundary.

Use non-production systems and data for evaluation.

Get started

• Install the CLI for offline authoring or to connect to an existing server.
• Assemble documents with nest to maintain one MongoDB document from related MySQL tables.
• Use the CLI reference and Troubleshooting for command and diagnostic details.