[python] Install _runtime_requirements.txt during lambda execution. by gscho · Pull Request #15011 · vercel/vercel

gscho · 2026-02-11T22:16:56Z

This needs to be merged and the package released before #14976

Warning

High Risk Change

This PR adds runtime dependency installation via subprocess during Lambda cold starts, modifying sys.path to prioritize dynamically installed packages - infrastructure change affecting Lambda execution behavior.

Adds subprocess.run to execute uv pip install during Lambda initialization
Modifies sys.path at runtime to insert /tmp/_vc_deps_overflow at front
Infrastructure: changes Lambda cold start behavior for Python runtime

^{Risk assessment for commit 8e9cde5.}

Signed-off-by: gscho <greg.c.schofield@gmail.com>

changeset-bot · 2026-02-11T22:17:01Z

🦋 Changeset detected

Latest commit: eaa1687

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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@vercel/python-runtime	Minor

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Signed-off-by: gscho <greg.c.schofield@gmail.com>

python/vercel-runtime/src/vercel_runtime/vc_init.py

Co-authored-by: vercel[bot] <35613825+vercel[bot]@users.noreply.github.com>

github-actions · 2026-02-12T05:58:23Z

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github-actions · 2026-02-12T05:58:43Z

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This PR was opened by the [Changesets release](https://github.com/changesets/action) GitHub action. When you're ready to do a release, you can merge this and the packages will be published to npm automatically. If you're not ready to do a release yet, that's fine, whenever you add more changesets to main, this PR will be updated. # Releases ## @vercel/build-utils@13.4.0 ### Minor Changes - [services] synchronize dependencies in dev mode for JS/TS and Python services ([#14987](#14987)) ### Patch Changes - Add new expirementalTrigger format for queues v2beta ([#14970](#14970)) - Updated dependencies \[[`a960cf23a42ff1a570c808ee9567670c24422f98`](a960cf2)]: - @vercel/python-analysis@0.4.1 ## vercel@50.16.0 ### Minor Changes - [services] synchronize dependencies in dev mode for JS/TS and Python services ([#14987](#14987)) - Add `contract` cli cmd for checking contract commitments ([#14735](#14735)) - Add `usage` command to check billing and usage information ([#14733](#14733)) ### Patch Changes - Add `--plan` flag to `vercel integration add` for specifying a billing plan ID ([#14965](#14965)) - Include the current Vercel CLI version in `.vercel/output/builds.json` generated by `vercel build`. ([#14999](#14999)) - Fixed deployment rate limit error message displaying incorrect retry time ([#14947](#14947)) - [services] services dev server orchestrator framework fallback fix ([#14985](#14985)) - Add new expirementalTrigger format for queues v2beta ([#14970](#14970)) - non-interactive mode for link - selectOrg ([#15003](#15003)) - non-interactive mode for link ([#15001](#15001)) - Remove tags column from `integration discover` table and compact terminal views to reduce width on small screens. Tags remain available in JSON output. ([#15000](#15000)) - non-interactive mode for link - enable for agents ([#15002](#15002)) - Add `--breakdown` option to `vercel usage` for viewing usage broken down by period ([#14741](#14741)) - Updated dependencies \[[`8f2c79045858cd41fa89522ee13f2ce5d6c81be1`](8f2c790), [`2686071de8e17161babea397fcd12226de8ecce9`](2686071), [`a960cf23a42ff1a570c808ee9567670c24422f98`](a960cf2)]: - @vercel/build-utils@13.4.0 - @vercel/python@6.12.0 - @vercel/backends@0.0.33 - @vercel/elysia@0.1.36 - @vercel/express@0.1.45 - @vercel/fastify@0.1.39 - @vercel/go@3.4.0 - @vercel/h3@0.1.45 - @vercel/hono@0.2.39 - @vercel/hydrogen@1.3.5 - @vercel/koa@0.1.19 - @vercel/nestjs@0.2.40 - @vercel/next@4.15.28 - @vercel/node@5.6.3 - @vercel/redwood@2.4.9 - @vercel/remix-builder@5.5.10 - @vercel/ruby@2.3.0 - @vercel/rust@1.0.5 - @vercel/static-build@2.8.37 ## @vercel/python@6.12.0 ### Minor Changes - [services] synchronize dependencies in dev mode for JS/TS and Python services ([#14987](#14987)) ### Patch Changes - log contents of malformed manifests ([#15019](#15019)) - Updated dependencies \[[`a960cf23a42ff1a570c808ee9567670c24422f98`](a960cf2)]: - @vercel/python-analysis@0.4.1 ## @vercel/backends@0.0.33 ### Patch Changes - Updated dependencies \[[`8f2c79045858cd41fa89522ee13f2ce5d6c81be1`](8f2c790), [`2686071de8e17161babea397fcd12226de8ecce9`](2686071)]: - @vercel/build-utils@13.4.0 ## @vercel/cervel@0.0.20 ### Patch Changes - Updated dependencies \[]: - @vercel/backends@0.0.33 ## @vercel/client@17.2.40 ### Patch Changes - Updated dependencies \[[`8f2c79045858cd41fa89522ee13f2ce5d6c81be1`](8f2c790), [`2686071de8e17161babea397fcd12226de8ecce9`](2686071)]: - @vercel/build-utils@13.4.0 ## @vercel/config@0.0.30 ### Patch Changes - Add new expirementalTrigger format for queues v2beta ([#14970](#14970)) ## @vercel/elysia@0.1.36 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.3 ## @vercel/express@0.1.45 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.3 - @vercel/cervel@0.0.20 ## @vercel/fastify@0.1.39 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.3 ## @vercel/gatsby-plugin-vercel-builder@2.0.135 ### Patch Changes - Updated dependencies \[[`8f2c79045858cd41fa89522ee13f2ce5d6c81be1`](8f2c790), [`2686071de8e17161babea397fcd12226de8ecce9`](2686071)]: - @vercel/build-utils@13.4.0 ## @vercel/h3@0.1.45 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.3 ## @vercel/hono@0.2.39 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.3 ## @vercel/koa@0.1.19 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.3 ## @vercel/mcp-adapter@0.3.2 ### Patch Changes - Fix .repository field in package.json to make it possible to publish ([#14997](#14997)) ## @vercel/nestjs@0.2.40 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.6.3 ## @vercel/node@5.6.3 ### Patch Changes - Updated dependencies \[[`8f2c79045858cd41fa89522ee13f2ce5d6c81be1`](8f2c790), [`2686071de8e17161babea397fcd12226de8ecce9`](2686071)]: - @vercel/build-utils@13.4.0 ## @vercel/python-analysis@0.4.1 ### Patch Changes - log contents of malformed manifests ([#15019](#15019)) ## @vercel/static-build@2.8.37 ### Patch Changes - Updated dependencies \[]: - @vercel/gatsby-plugin-vercel-builder@2.0.135 ## @vercel/python-runtime@0.4.0 ### Minor Changes - Install \_runtime_requirements.txt during lambda execution if provided. ([#15011](#15011)) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Install _runtime_requirements.txt during lambda execution.

546b2aa

Signed-off-by: gscho <greg.c.schofield@gmail.com>

gscho requested review from a team as code owners February 11, 2026 22:16

gscho changed the title ~~Install _runtime_requirements.txt during lambda execution.~~ [python] Install _runtime_requirements.txt during lambda execution. Feb 12, 2026

vercel bot had a problem deploying to Preview February 12, 2026 01:25 Failure

Remove manual version bump and undo fmt.

4a3e191

Signed-off-by: gscho <greg.c.schofield@gmail.com>

gscho force-pushed the gscho/vc-init-runtime-dep-install branch from de5feef to 4a3e191 Compare February 12, 2026 01:26

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elprans approved these changes Feb 12, 2026

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Merge branch 'main' into gscho/vc-init-runtime-dep-install

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tknickman approved these changes Feb 12, 2026

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Merge branch 'main' into gscho/vc-init-runtime-dep-install

8e9cde5

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gscho merged commit 387a47f into main Feb 12, 2026
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gscho deleted the gscho/vc-init-runtime-dep-install branch February 12, 2026 14:09

vercel-release-bot mentioned this pull request Feb 12, 2026

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[python] Install _runtime_requirements.txt during lambda execution.#15011

[python] Install _runtime_requirements.txt during lambda execution.#15011
gscho merged 5 commits intomainfrom
gscho/vc-init-runtime-dep-install

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