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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 55 of the last 60 stable releases
Nothing withdrawn
no release was ever pulled
8 years old
210 releases · first in 2019
jsii-rosetta transliterate: transliterate a jsii assembly
One column per quarter.
jsii-rosetta transliterate: transliterate a jsii assembly
rosetta: JSII_ROSETTA_MAX_WORKER_COUNT limits max workers
deprecated symbol stripping does not strip out heritage clause with imported type
go: retracted github.com/aws/jsii-runtime-go@v1.27.0 as it was unusable.
go: variadic type helpers to build slices
go,python/java: if multiple members have the same name with different capitalization, only one is allowed to be non-deprecated. This will currently on…
$NVM_USE_VERSION selects Node.js version (#2726) (fb9abf9)go: packageName and versionSuffix (#2687) (9562108), related to #2632
go: support direct implementation of jsii interfaces (#2614) (9da3282), closes #2048
go: emit indirect dependencies in go.mod
--outdir in some cases (#2584) (b9b9b4c)go: map values incorrectly handled though de/serialization
--outdir in some cases (#2584) (b9b9b4c)pacmak: examples with multi-line strings produce invalid python docstrings (#2571) (d5c2e3a), closes #2569
python: ValueError: write to closed file
add runtime type info (fqn and version) to compiled sources (481e7a4), closes /github.com/aws/aws-cdk-rfcs/blob/master/text/0253-cdk-metadata-v2.md#ap
jsii: experimental --strip-deprecated feature
jsii-reflect (#2482) (33f41eb)python: process.terminate() got an unexpected keyword argument 'timeout' (#2421), closes #2398
add support for bin-scripts (python only)
java: exception is logged when Java VM is shutting down (#2305) (8e1e7bd), closes #2303
dotnet,java: finalize kernel process on VM shutdown (#2247) (29b2262), closes #2100
python: update cattrs dependency specification (#2212) (d7731f9), closes aws/aws-cdk#11219
cattrs dependency specification (#2212) (d7731f9), closes aws/aws-cdk#11219The jsii/superchain Docker image no longer includes ruby and gcc. Users who need those should install them as part of their initialization script.
jsii/superchain Docker image no longer includes ruby and gcc. Users who need those should install them as part of their initialization script.UnsafeCast<T>() method (#2192) (5e22e81), closes aws/aws-cdk#3284 aws/aws-cdk-rfcs#193dotnet: abundant nullability warnings in generated code (#2061) (01a2951)
go: fix generation of readonly and static properties (#2133) (57b7d56), closes #2093
jsii: annotation '@internal' causes missing type declarations downstream (#2172) (e80a4f7), closes #1947 #1830
jsii: TypeError: Cannot read property 'getJsDocTags' of undefined (#2163) (5d87101), closes #2098
jsii-diff: external structs returned from methods cannot be changed (#2070) (11e9389), closes #2064
pacmak/python: escape character escapes in python docs (#2138) (1578899), closes #2137
python: leftover jsii-kernel-* directories in TMPDIR (#2100) (c119994)
removes unused software from superchain to reduce image size (#2092) (fe2c597)
jsii: reflect stabilities in doc comment summaries
golang: introduce Golang code generation (#1551) (2833db4), closes #83
undefined (#1932) (3b48778)jsii: detect changing visibility when overriding (#1876) (cfc99c2), closes aws/aws-cdk#9616
EMFILE error when running jsii-pacmak (#1891) (7316b44)java: user.xml repository ID was not sanitized
jsii-reflect: TypeSystem.methods and .properties ignores submodules
kernel: tarball unpacking does not behave like 'npm install' (#1766) (2dc1b21), closes aws/aws-cdk#8233 #1765
jsii-pacmak: add maven and nuget support for * dependencies (#1696) (13667f6), closes aws/jsii#1678
java: add a Builder interface implemented by all builders (#1654) (52e73b5), closes #1652
self as property name leads to assignment error (#1330) (a877f34)jsii: unable to use type from dependencies' submodules
java: compilation fails with "code too large"
python: incorrect dependency on jsii (#1582) (c537bd7), closes #1573
jsii-pacmak: invalid dotnet version suffixes
compliance: produce compliance test reports
jsii: introduce submodules feature (#1297) (2df5d90), closes #1286
java: invalid collections returned with non-class elements (#1197) (bbc2302), closes #1196
java: maven-surefire-plugin 2.22.2
rosetta: crashes on behavioral interfaces
dotnet: documentation strings sometimes invalid
--watch causes immediate failure (#1150) (6bdf7d7), closes #1149rosetta: "Rosetta configured for live conversion to undefined"
reflect: failure to load assembly from "npm pack"
allow Missing Dotnet Version Suffix (#1047) (fc366d0), closes #1037
Move jsii-spec to Dependencies (#1032) (0581323), closes #1030
java: handle null-able collections correctly (#986) (e88e5e2), closes aws/aws-cdk#4316
python: dynamic proxies handling of setters (eec9640), closes aws/aws-cdk#5032
dotnet: allow down-casting to parent interface type (#983) (8a390e5), closes #982
python: correctly handle nested structs-as-dict
kernel: correctly de-serialize mappings as JSON
pacmak: .NET build downloading packages from NuGet
dotnet/analyzer: remove dependency on Runtime
java: correctly search for protected override implementations (#905) (e3f0f6c), closes #903
jsii: Correct the 'types' attribute in package.json
dotnet: use snupkg format for dotnet symbol packages (#830) (0d18b4d), closes NuGet/Home#6082
dotnet: use snupkg format for dotnet symbol packages (#830) (d2724f0), closes NuGet/Home#6082
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