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PyPI · #1588 most downloaded on PyPI
Python client for jsii runtime
Last release today
01 Oct 2026
Ships fairly regularly
a new release about every 2 weeks
Nearly every release is documented
notes for 54 of the last 60 stable releases
Nothing withdrawn
no release was ever pulled
8 years old
210 releases · first in 2019
Nothing published for this version
go: register exported properties as callbacks (#4104) (fa921ec), closes cdk8s-team/cdk8s#1326
One column per quarter.
jsii-diff: allow external stability to be treated as error
rosetta: handle tablets with a streaming JSON codec (#4034) (d2ecb6d), closes aws/jsii-rosetta#43
pacmak: runtime dependency should match pacmak release
jsii-reflect now renders union candidates sorted
null value (#4000) (884b0ff), closes aws/aws-cdk#14639dotnet: The runtime library for .NET & generated .NET bindings will no longer support netcoreapp3.1 after this release. Users are advised to upgrade t
check-node: export NodeRelease class
python: returning Promise breaks runtime
Nothing published for this version
check-node: allow silencing @jsii/check-node warnings (#3841) (880dbcc), closes #3817 #3171
jsii: missing deprecation warning in collections (#3756) (72f2e7c), closes #3755
kernel: distinguish framework errors from userland errors in Java
java: dynamic type checking for union-typed parameters
go: emit deprecation warning when using go1.16 and go1.17
python: reference to type does not use alias
pacmak: allow opt-out of runtime type checking generation
pyhon: under-qualified types used by dynamic type checking
python: formally allow dicts to be passed in lieu of structs
jsii: allow specifying baseUrl and paths in tsconfig.json (#3662) (7eb11b7), closes #865
@jsii/spec: add loadAssemblyFromBuffer function
add support for using custom .m2 directory
@aws-cdk/check-node fails to load on older (EOL) releases of node
Beginning with this release, jsii packages no longer support node 12. Users should migrate to a supported node release (14.x, 16.x, or 18.x).
jsii: deprecation warnings use this.constructor before calling super (#3528) (5d5f435), closes #3527
jsii-pacmak and the libraries it generates for Python targets now require a minimum Python version of 3.7, instead of 3.6 previously. We recommend use
jsii-pacmak and the libraries it generates for Python
targets now require a minimum Python version of 3.7, instead of 3.6
previously. We recommend users upgrade to the latest supported Python
release (Python 3.10).go: object type not recognized (#3485) (fe2fa94), closes #2880
jsii: some submodules are not exported from aws-cdk-lib (#3491) (47f70a2)
pacmak: missing python artifacts when using relative -o path (#3518) (cc9b561), closes aws/aws-cdk#20041
rosetta: attempts transliteraiton to unsupported languages (#3478) (db2d62e)
rosetta: incorrect transliteration for selective imports (#3508) (8eec086)
drop support for Python 3.6 (EOL as of 2021-12-23) (#3472) (abf7415)
go: object type not recognized (#3485) (fe2fa94), closes #2880
drop internal functions from Deprecation Error stack trace
Nothing published for this version
go: lots of documentation is missing from generated code
jsii: dependencies' README files are unnecessarily re-rendered
add configuration for Visual Studio Code
colors (#3328) (13c0737)jsii: breaks due to faulty version of colors
rosetta: transliterate tries to recompile samples from tablets (#3324) (7aa69a7), closes #3262
pacmak: go yaml struct tags (#3299) (63132cf), closes #3293
jsii: color codes are logged to logfiles
improve compatibility with restricted-export modules
rosetta extract fails if run after rosetta infuse (#3248) (e3ec929)jsii: deprecation message is not displayed for deprecated classes
allTypes accessor (#3194) (41f301a)--infuse option for extract (#3210) (ccb3c57)extract ignores --compile option (#3193) (639c510)--compile flag by default (#3218) (9df7950)jsii: deprecation message is not displayed for deprecated classes
allTypes accessor (#3194) (41f301a)--infuse option for extract (#3210) (ccb3c57)extract ignores --compile option (#3193) (639c510)--compile flag by default (#3218) (9df7950)rosetta: extract ignores --compile option
C# NamespaceDoc emitted to wrong location
jsii: require statement for the warning file is generated when it's not used
revert "fix: dependency submodules may not be discovered"
deprecation warnings are generated even when one property is not deprecated
didCompile evaluates to true when compilation not attempted (#3149) (7ad9e0a)pacmak: fail on untranslated snippets (#3127) (874e8e2), closes cdklabs/cdk-ops#1777
infuse creates untranslated examples (#3126) (ab60275)jsii: deprecation warnings erroneously warn for duplicate enum values (#3105) (c477422), closes #3103
jsii: experimental --strip-deprecated with file
jsii: added warnings for usage of deprecated elements
jsii: added a symbol identifier to every type in the assembly
any (#3043) (3d2ba15), closes #3029! and === operators (#3052) (72b9b98), closes #2993I are incorrectly interpreted as non-structs (#3040) (d564350)declare statements (#3044) (4ccacd1)asList into List.of (#3048) (ee75bf1)jsii-pacmak: modules not packed in topological order
pacmak: opt out of jsii assembly validation
Nothing published for this version
the minimum supported version of node changed from 10.3.0 to 12.7.0. We recommend using 16.x if possible.
node changed from
10.3.0 to 12.7.0. We recommend using 16.x if possible.superchain: the jsii/superchain image tags :latest, :nightly, :node10 and :node14 are no longer maintained. Users should migrate to the new debian-bas
jsii/superchain image tags :latest, :nightly,
:node10 and :node14 are no longer maintained. Users should migrate to
the new debian-based tags starting with :1-buster-slim.java: Disable covariants for java builder params (#2853) (e729f5d), closes #2839
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