---
title: "Change log"
description: "This page lists user-visible changes to the Python SDK, newest first; each section covers the changes since the previous release of this component."
canonical_url: "https://docs.superdurable.io/reference/python/changelog/"
source: "docs/reference/python/changelog.mdx"
locale: "en"
---

# Change log

This page lists user-visible changes to the Python SDK, newest first; each section covers the changes since the previous release of this component.

<a id="v1-45"></a>

## 1.45

Released 2026-11-11 as [sdk-python/v1.45.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.45.0).

### Added

- **WorkerOptions.flow_definition_paths** and **WorkerOptions.flow_definitions** make a Worker upload Flow Definition Graph documents when it starts, so Dex Web can draw its Flows without a definition directory. The Worker uploads only registered Flow types, shares **source.path** only as a relative path, and keeps starting when the upload fails. **FlowDefinitionDocument** describes an in-memory document. Requires server-zd 0.1.26 or later. [Reference](https://docs.superdurable.io/reference/python/workers.md#flow-definitions).
- **Client.upload_flow_definitions** uploads Flow definitions from a deploy script and returns a **FlowDefinitionUploadResult** with a **FlowDefinitionUploadOutcome** for each document. **AsyncClient** has the same coroutine. [Reference](https://docs.superdurable.io/reference/python/workers.md#flow-definitions).

### Breaking

- A Step whose Step type contains "-" can no longer start SubFlows. A dash made the generated child Flow ID ambiguous, so two parents could share one child. When such a Step returns a Wait that contains **SubFlow\.run**, the server rejects the result as an invalid Worker response and fails the attempt without retry. The Worker logs a warning first. Default Step types are class names and are not affected. To migrate, change **get_step_type** to return a Step type without a dash. [Reference](https://docs.superdurable.io/reference/python/subflow.md#step-types-that-start-subflows).

### Fixed

- The **Join** documentation no longer recommends reporting a result for a cancelled branch from the cancelling RPC, which could count that branch twice. A cancelled branch never reports, and no other code can safely report for it. [Reference](https://docs.superdurable.io/reference/python/waits.md).

<a id="v1-44"></a>

## 1.44

Released 2026-11-10 as [sdk-python/v1.44.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.44.0).

### Added

- **Join** and **JoinRound** synchronize parallel branches of a Flow. **Join.fork** starts a round from the split Step and builds the branch and join movements, so the application keeps no branch count or round key. Branches report with **end_branch** or **report_branch_result**. The join Step waits with **for_all_branches**, **for_first_branch**, or **for_branches**, and the next round resets the previous one with **for_remaining_branches**. RPC handlers use **fork_with_round_key**. **Join.channel_map** returns the registered ChannelMap, so an RPC can load and read a round's pending results. [Reference](https://docs.superdurable.io/reference/python/waits.md).

<a id="v1-43"></a>

## 1.43

Released 2026-11-10 as [sdk-python/v1.43.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.43.0).

### Breaking

- Removed **Client.trigger_continue_as_new**, **AsyncClient.trigger_continue_as_new**, **FlowStatus.CONTINUED_AS_NEW**, **FlowConfig.continue_as_new_threshold**, **FlowConfig.continue_as_new_page_size_bytes**, and **include_continued_as_new** from both clients' **search_flows** methods. [Reference](https://docs.superdurable.io/reference/python/flow.md#flow-config).
- **FlowConfig** is a dataclass, and the two removed fields were its second and third fields. Every later field moves two positions forward, so a positional **FlowConfig** call can set the wrong field. Construct **FlowConfig** with keyword arguments. [Reference](https://docs.superdurable.io/reference/python/flow.md#flow-config).
- Removed **WaitForStepCompletionOptions.internal_handler_timeout** and **WaitForAttributeOptions.internal_handler_timeout**. **request_id** remains accepted but the server does not read it for these waits. [Reference](https://docs.superdurable.io/reference/server/runtime-client.md#wait-timeouts-and-limits).
- Generated bindings rename **FlowExecutionID** to **FlowRunID** and **flow_execution_id** to **flow_run_id**. ProtoJSON uses **flowRunId**. [Reference](https://docs.superdurable.io/reference/server/runtime-client.md#describe-a-flow).

<a id="v1-40"></a>

## 1.40

Released 2026-11-09 as [sdk-python/v1.40.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.40.0).

### Added

- **FlowConfig.offload_history** chooses whether a run offloads its history to object storage. None means True. Set it to False for many short runs that close soon. Set it at start through **StartFlowOptions.config_override** or **SubFlowOptions.config_override**. A SubFlow otherwise inherits its parent's value, and **update_flow_config** rejects it with INVALID_ARGUMENT. It requires server-zd 0.1.23 or later. [Reference](https://docs.superdurable.io/reference/server/configuration.md#history-offload).

### Changed

- **FlowConfig.delete_expired_history_objects** is deprecated. It has no effect, and the SDK no longer sends it. Existing code that sets it still compiles.

<a id="v1-39"></a>

## 1.39

Released 2026-11-09 as [sdk-python/v1.39.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.39.0). Patch release [sdk-python/v1.39.1](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.39.1) followed the same day.

### Added

- **Action** and **when_attribute_matches** declare an RPC that a person can invoke from Dex Web: pass an **Action** with a label, a required permission, and a condition as the **action** argument of **@rpc**. The condition is optional. Workers send the Flow's Action permission mappings, and **start_flow** and SubFlow starts record the permissions the initial Attributes make available. This arrived in 1.39.1. [Reference](https://docs.superdurable.io/reference/web/dex-web.md#actions).
- **FlowConfig.delete_expired_history_objects** controls expired history object deletion at start, on update, and for SubFlows. It requires history offload and server-zd 0.1.22 or later.

### Changed

- A LoadBlobs request names at most 1,000 entries. The SDK batches larger requests and keeps the input order.

<a id="v1-38"></a>

## 1.38

Released 2026-11-07 as [sdk-python/v1.38.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.38.0).

### Added

- **FlowConfig.history_window_events** sets about how many of the newest history events a run keeps for history reads and Time Travel. Set it at start, change it with **update_flow_config**, or override it for a SubFlow. None uses the server's **history.windowEvents** setting. Dex rejects a value that is not positive or exceeds **history.maxWindowEvents** with INVALID_ARGUMENT. It requires server-zd 0.1.21 or later. [Reference](https://docs.superdurable.io/reference/server/configuration.md#history-window).

### Changed

- The gRPC receive limit rises from 4 MiB to **DEFAULT_GRPC_MAX_MESSAGE_BYTES** (32 MiB) on every FlowService and pull stream channel. Set **grpc_max_message_bytes** on **ClientOptions** or **WorkerOptions** to change it.

### Fixed

- A LoadBlobs request splits in half when its response exceeds a gRPC size limit, so a Worker with an empty blob cache no longer fails on a long Flow. A single blob that does not fit raises the new **BlobMessageTooLargeError**.

<a id="v1-37"></a>

## 1.37

Released 2026-11-06 as [sdk-python/v1.37.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.37.0). Reference: [1.37.x](https://docs.superdurable.io/reference/python/1.37.x.md).

### Added

- **FlowServiceTlsOptions** and **flow_service_tls** on Client and Worker options enable verified TLS, with optional extra root CAs and a server-name override. Omitting the option keeps plaintext connections. [API reference](https://docs.superdurable.io/api/python/latest/dex.html#FlowServiceTlsOptions).

<a id="v1-35"></a>

## 1.35

Released 2026-11-06 as [sdk-python/v1.35.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.35.0). Reference: [1.35.x](https://docs.superdurable.io/reference/python/1.35.x.md).

### Breaking

- Workers and the Client’s first call now require server-zd 0.1.17 or later (protocol version 4). Upgrade all server processes before upgrading the SDK. [Reference](https://docs.superdurable.io/reference/server/upgrades.md).
- Worker startup fails when **max_concurrent_tasks** exceeds **matching.maxConcurrentTasksCap** (256 by default). Lower the Worker setting or raise the server cap and **matching.maxStreams** first. [Reference](https://docs.superdurable.io/reference/python/workers.md#capacity-and-shutdown).
- **RetryPolicy.total_duration** now starts at the first hand-out and only gates scheduling another retry. Set method timeouts to bound running attempts. [API reference](https://docs.superdurable.io/api/python/latest/dex.html#RetryPolicy.total_duration).
- A Step with no available or supporting Worker waits durably without consuming a retry. Set a Flow timeout to bound that wait. [Reference](https://docs.superdurable.io/reference/server/workers.md#step-task-queue).
- A Step attempt interrupted after its hand-out was committed fails with **NOT_COMPLETED** and consumes a retry. Review retry policies and side effects before upgrading. [Reference](https://docs.superdurable.io/reference/python/failure-and-retries.md#same-attempt-redelivery).

### Added

- **RecoveryErrorInfo.attempt_progress** distinguishes a failed Step method that never started from one that may have run. [API reference](https://docs.superdurable.io/api/python/latest/dex.html#RecoveryErrorInfo.attempt_progress).

### Changed

- Workers open one execution stream per slot; **reserved_rpc_tasks** selects RPC-only slots. By default, a Worker with at least two slots reserves one for RPCs. [Reference](https://docs.superdurable.io/reference/python/workers.md#capacity-and-shutdown).
- **stop** drains running handlers and returns tasks that did not start without consuming a retry. [Reference](https://docs.superdurable.io/reference/python/workers.md#capacity-and-shutdown).

### Deprecated

- **idle_streams_per_queue** is accepted but ignored, and **pull_reserved_rpc_declines** always reports zero. Use execution-slot capacity and queue metrics instead. [Reference](https://docs.superdurable.io/reference/python/workers.md#reserved-rpc-capacity).

<a id="v1-32"></a>

## 1.32

Released 2026-11-01 as [sdk-python/v1.32.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.32.0). Reference: [1.32.x](https://docs.superdurable.io/reference/python.md).

### Added

- Generated protocol bindings include **AdminService**, with **DescribeActiveNode** and **StepDownActiveNode** for inspecting and stepping down the active server process. [Release notes](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.32.0).

<a id="v1-30"></a>

## 1.30

Released 2026-10-31 as [sdk-python/v1.30.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.30.0). Reference: [1.30.x](https://docs.superdurable.io/reference/python.md).

### Added

- Generated protocol bindings add **ERROR_SUB_STATUS_ATTRIBUTE_INDEX_CAPACITY_EXCEEDED** and **ERROR_SUB_STATUS_INDEXED_KEYWORD_TOO_LONG** for Attribute index admission errors. [Release notes](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.30.0).

<a id="v1-29"></a>

## 1.29

Released 2026-10-31 as [sdk-python/v1.29.0](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.29.0). Reference: [1.29.x](https://docs.superdurable.io/reference/python.md).

### Added

- Generated history responses expose the pruned event range and first retained event ID. Step event contexts also carry related event IDs and the WaitFor completion time. [Release notes](https://github.com/superdurable/dex/releases/tag/sdk-python%2Fv1.29.0).
- **Client.get_attributes** and **AsyncClient.get_attributes** read committed Attributes and AttributeMap instances in one request without a Worker. **AttributeMap.instance** selects an instance, and **AttributeValues** provides typed result lookup. [API reference](https://docs.superdurable.io/api/python/latest/dex.html).

Older releases: [GitHub releases](https://github.com/superdurable/dex/releases?q=sdk-python\&expanded=true).