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npm · #794 most downloaded on npm
Last release 4 days ago
30 Sep 2026
Ships fairly regularly
a new release about every 9 days
Nearly every release is documented
notes for 60 of the last 60 stable releases
7 versions withdrawn
withdrawn after publishing
3 years old
166 releases · first in 2023
4734e1c : fix for SDK ServiceException instanceof detection relating to mangled class names
596456b : add per-request MetricsRecorder support through client.send(command, { metricsRecorder })
client.send(command, { metricsRecorder })One column per month.
90e722f : error and backpressure fixes for AWS chunked encoding streams
c45b1ba : Add custom error classes to identify and differentiate Smithy runtime errors from other errors.
e82a22b : fix: handle exponent notation when serializing NumericValue wrappers
99c3f91: Restore npm provenance attestations. No functional changes.
b3958ad: fix for RPC protocol event stream initial messages
cf69285: offer the client logger to request handlers as a fallback without overwriting a handler's own logger. A NoOpLogger is not offered, so handler
NoOpLogger is not offered, so handlers keep their console-based defaults.ec9b4b2: chore: update builds to use typescript 6. This should not affect consumers, who may continue to use TypeScript 3.4 through 7.0 as of this ver
fcf1366: switch cbor codec to use single-pass (v2) shape serializer and deserializer
a14bb71: add single pass cbor serializer and deserializers
155bb56: updating errors list for clock skew errors (retryable)
d6e6f8b: update large map threshold in cbor
44b21e6: fix for event stream events - throw the specific modeled error class instead of a generic Error
3248fbd: add missing service-specific endpoint features
b44cb0a: handle early closure of underlying stream in ChecksumStream
5fca3a0: Add typesVersions entries for submodules so TypeScript <4.5 consumers resolve submodule types
### Patch Changes - Updated dependencies [a97abc3] - @smithy/types@4.16.1
273e480: types updates for isolatedModules=true
1fac409: Make ChecksumStream a Readable that consumes its source directly
12bceb2: add internal higher order factory for Command classes
d366537: Add IMDSv2 region fallback to NODE_REGION_CONFIG_OPTIONS default, consolidated with defaults-mode region inference.
c9575e1: add crc32 and sha256 checksum impls
3cfda3b: CBOR performance improvements
63ddca4: deferred loading for core/event-streams for use in client config initializers
17e50e9: update dist-cjs output format to use plain require/exports statements
13e74d6: add upper bound for Retry-After delay in deprecated StandardRetryStrategy
776bc52: update adaptive rate limiter to execute directly prior to outgoing requests & retries
721fbed: remove and prevent circular file-level dependencies
9eaa5c6: add bundler compatibility for tsup
### Patch Changes - Updated dependencies [cf00244] - @smithy/types@4.14.2
6d4eb8a: fix for browser utf8 variant not to include Buffer (Node.js)
2dc5cf6: fix for uuid generation in Node.js 18.x
540aeb4: consolidate core/retry and related cleanup
### Patch Changes - @smithy/util-stream@4.5.25
a029f0e: Reduce intermediate allocations in hot paths
### Patch Changes - Updated dependencies [131fce4] - Updated dependencies [52b4789] - @smithy/types@4.14.1 - @smithy/util-stream@4.5.23 - @smithy/prot
### Patch Changes - Updated dependencies [cffd868] - @smithy/types@4.14.0 - @smithy/protocol-http@5.3.13 - @smithy/url-parser@4.2.13 - @smithy/util-mi
7198e09: Remove unnecessary shallow copy of input object and delete operations in HttpBindingProtocol.serializeRequest and RpcProtocol.serializeReques
HttpBindingProtocol.serializeRequest and RpcProtocol.serializeRequest. The body serializer is schema-driven and only reads members listed in the payload schema, making the spread and deletes redundant. This eliminates an O(n) copy and 5 delete operations per request.
### Patch Changes - @smithy/util-stream@4.5.20
2edd638: feat(schema): add caching to NormalizedSchema.of() and translateTraits()
5340b11: apply resolved endpoint headers to final request
6ef5430: fix typo in thrown error message
a4d95e6: Set downlevel types to be used in typescript@'<4.5'
11569eb: preserve null values for non-sparse collections in cbor deserializing
@smithy/middleware-serde@4.2.11
026b177: fix(protocols): remove unsafe type cast in resolvedPath to handle null/undefined from labelValueProvider
03c3dc8: update for rollup build externalLiveBindings=false
### Patch Changes - Updated dependencies [ffe1843] - @smithy/util-stream@4.5.13
c5db01c: fix for Unit event stream union targets
6f96c01: omit absent resposne fields instead of assigning undefined
4f05c6a: compose error TypeRegistry on protocol
### Patch Changes - @smithy/util-stream@4.5.11
472bf01: avoid autoboxing in NormalizedSchema::getSchema()
fa0e0c4: accept 0-byte event stream payloads as structure shapes
c2a6f46: improve schema struct iterator performance
96cc077: limit scope of http label validation
ae6ef2e: client side httpLabel validation
862c942: custom handling for \_\_type in structures
### Patch Changes - Updated dependencies [745867a] - @smithy/types@4.12.0 - @smithy/middleware-serde@4.2.9 - @smithy/protocol-http@5.3.8 - @smithy/uti
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