[build-utils] Align deserialize logic with existing callers by healeycodes · Pull Request #16002 · vercel/vercel

healeycodes · 2026-04-16T15:18:30Z

While I was integrating #15961 for existing callers, I saw that we are slightly changing the behavior of prerenders.

This PR fixes the differing semantics and unblocks this migration work.

changeset-bot · 2026-04-16T15:18:39Z

🦋 Changeset detected

Latest commit: d876e6b

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

This PR includes changesets to release 16 packages

Name	Type
@vercel/build-utils	Patch
@vercel/backends	Patch
vercel	Patch
@vercel/client	Patch
@vercel/elysia	Patch
@vercel/express	Patch
@vercel/fastify	Patch
@vercel/fs-detectors	Patch
@vercel/gatsby-plugin-vercel-builder	Patch
@vercel/h3	Patch
@vercel/hono	Patch
@vercel/koa	Patch
@vercel/nestjs	Patch
@vercel/node	Patch
@vercel/static-build	Patch
@vercel/cervel	Patch

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vercel · 2026-04-16T15:19:51Z

Low Risk — Build utils refactor: moves boundary generation to module scope for consistency + adds TypeScript generics + tests.

prerender-to-build-output-file.ts: moved boundary generation from function scope to module scope for consistent multipart boundaries
serialized-types.ts: added generic type parameters to SerializedLambda and SerializedNodejsLambda types
unit.deserialize-lambda.test.ts: added new test file for deserializeLambda with subclass preservation

^{Assessed at d876e6b.}

github-actions · 2026-04-16T15:21:01Z

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github-actions · 2026-04-16T15:22:27Z

🧪 Unit Test Strategy

Comparing: 7b1db35 → d876e6b (view diff)

Strategy: Code changed outside of a package - running all unit tests

⚠️ All unit tests will run because global code changes could impact all packages.

Affected packages - 40 (100%)

@vercel-internals/get-package-json
@vercel/backends
@vercel/build-utils
@vercel/cervel
@vercel/cli-auth
@vercel/client
@vercel/config
@vercel/detect-agent
@vercel/edge
@vercel/elysia
@vercel/error-utils
@vercel/express
@vercel/fastify
@vercel/firewall
@vercel/frameworks
@vercel/fs-detectors
@vercel/functions
@vercel/gatsby-plugin-vercel-builder
@vercel/go
@vercel/h3
@vercel/hono
@vercel/hydrogen
@vercel/koa
@vercel/nestjs
@vercel/next
@vercel/node
@vercel/oidc
@vercel/oidc-aws-credentials-provider
@vercel/python
@vercel/python-analysis
@vercel/redwood
@vercel/related-projects
@vercel/remix-builder
@vercel/routing-utils
@vercel/ruby
@vercel/rust
@vercel/static-build
@vercel/static-config
examples
vercel

Results

Unit tests: All affected packages will run unit tests
E2E tests: Running in parallel via E2E Tests workflow
Type checks: All affected packages will run type checks

This comment is automatically generated based on the affected testing strategy

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/backends@0.0.63 ### Patch Changes - Typecheck deployment TypeScript via the compiler API (entry + import graph), deduplicate the cervel `typescript` module, and extend the turborepo fixture with a chained `tsconfig` for monorepo path resolution. ([#15980](#15980)) - Relax failures when we don't find an entrypoint for backends to maximize backwards compatibility ([#15980](#15980)) - Updated dependencies \[[`5219572d21a2ba4b49cc1c27d244c1ff5d76c591`](5219572)]: - @vercel/build-utils@13.17.1 ## @vercel/build-utils@13.17.1 ### Patch Changes - Align deserialize logic with existing callers. ([#16002](#16002)) ## @vercel/cervel@0.0.50 ### Patch Changes - Updated dependencies \[[`2babfa22946d80a92f1307a8d860a9039d695b09`](2babfa2), [`2babfa22946d80a92f1307a8d860a9039d695b09`](2babfa2)]: - @vercel/backends@0.0.63 ## vercel@51.5.1 ### Patch Changes - Improve Claude Code Vercel plugin install and update prompts across CLI commands. ([#15921](#15921)) - Updated dependencies \[[`5219572d21a2ba4b49cc1c27d244c1ff5d76c591`](5219572), [`2babfa22946d80a92f1307a8d860a9039d695b09`](2babfa2), [`2babfa22946d80a92f1307a8d860a9039d695b09`](2babfa2), [`adbe6f0a0152136aa26aa1277458f4578f62beeb`](adbe6f0)]: - @vercel/build-utils@13.17.1 - @vercel/backends@0.0.63 - @vercel/python@6.33.2 - @vercel/elysia@0.1.66 - @vercel/express@0.1.76 - @vercel/fastify@0.1.69 - @vercel/go@3.5.0 - @vercel/h3@0.1.75 - @vercel/hono@0.2.69 - @vercel/hydrogen@1.3.6 - @vercel/koa@0.1.49 - @vercel/nestjs@0.2.70 - @vercel/next@4.16.8 - @vercel/node@5.7.8 - @vercel/redwood@2.4.12 - @vercel/remix-builder@5.7.2 - @vercel/ruby@2.3.2 - @vercel/rust@1.1.1 - @vercel/static-build@2.9.16 ## @vercel/client@17.3.5 ### Patch Changes - Updated dependencies \[[`5219572d21a2ba4b49cc1c27d244c1ff5d76c591`](5219572)]: - @vercel/build-utils@13.17.1 ## @vercel/elysia@0.1.66 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.7.8 ## @vercel/express@0.1.76 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.7.8 - @vercel/cervel@0.0.50 ## @vercel/fastify@0.1.69 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.7.8 ## @vercel/fs-detectors@5.18.1 ### Patch Changes - Updated dependencies \[[`5219572d21a2ba4b49cc1c27d244c1ff5d76c591`](5219572)]: - @vercel/build-utils@13.17.1 ## @vercel/gatsby-plugin-vercel-builder@2.1.16 ### Patch Changes - Updated dependencies \[[`5219572d21a2ba4b49cc1c27d244c1ff5d76c591`](5219572)]: - @vercel/build-utils@13.17.1 ## @vercel/h3@0.1.75 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.7.8 ## @vercel/hono@0.2.69 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.7.8 ## @vercel/koa@0.1.49 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.7.8 ## @vercel/nestjs@0.2.70 ### Patch Changes - Updated dependencies \[]: - @vercel/node@5.7.8 ## @vercel/node@5.7.8 ### Patch Changes - Updated dependencies \[[`5219572d21a2ba4b49cc1c27d244c1ff5d76c591`](5219572)]: - @vercel/build-utils@13.17.1 ## @vercel/python@6.33.2 ### Patch Changes - Update the error for custom installCommand builds >250MB. ([#15946](#15946)) ## @vercel/static-build@2.9.16 ### Patch Changes - Updated dependencies \[]: - @vercel/gatsby-plugin-vercel-builder@2.1.16 Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Building on previous PRs: - #15927 - #15961 - #16002 We are extracting the core `deserialize-build-output.ts` file here. This is following refactor efforts in the existing caller codebases to make this extraction simpler. After shipping this extraction, we'll delete the duplicated code and import `deserializeBuildOutput` from this PR. Doing this should introduce zero semantic changes for those callers. Note: callers must inject their own `groupLambdas` strategy. Note2: some existing TODO comments have been left in-place as code documentation.

[build-utils] Align deserialize logic with existing callers

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healeycodes requested a review from ofhouse April 16, 2026 15:18

healeycodes requested a review from a team as a code owner April 16, 2026 15:18

healeycodes enabled auto-merge (squash) April 16, 2026 15:19

vercel Bot deployed to Preview April 16, 2026 15:20 View deployment

Melkeydev approved these changes Apr 16, 2026

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d876e6b

vercel Bot deployed to Preview April 16, 2026 15:52 View deployment

ofhouse approved these changes Apr 16, 2026

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healeycodes merged commit 5219572 into main Apr 16, 2026
254 of 257 checks passed

healeycodes deleted the deserialize-alignment branch April 16, 2026 18:04

vercel-cli-release-bot mentioned this pull request Apr 16, 2026

Version Packages #16003

Merged

healeycodes mentioned this pull request Apr 20, 2026

[build-utils] Extract main deserialize-build-output file #16048

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[build-utils] Align deserialize logic with existing callers#16002

[build-utils] Align deserialize logic with existing callers#16002
healeycodes merged 2 commits into
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deserialize-alignment

healeycodes commented Apr 16, 2026

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