fix(eve): instrumentation - preload before server dependencies by AndrewBarba · Pull Request #1302 · vercel/eve

AndrewBarba · 2026-07-28T21:46:19Z

Summary

preload authored instrumentation before bundled server entry imports
allow OpenTelemetry auto-instrumentations to patch external dependencies such as pg
guard instrumentation setup across the preload and Nitro plugin module instances
document the build.externalDependencies requirement for auto-instrumented packages

Root cause

Nitro inlined the instrumentation plugin body into the server entry while external dependency imports were hoisted above it. ESM therefore evaluated dependencies such as pg before registerOTel installed its module hook.

Validation

relevant unit tests: 22 passed
instrumentation and Nitro host scenarios: 18 passed
hosted instrumentation dependency scenario: passed
TypeScript check: passed
clean merge validated against current main

OpenTelemetry auto-instrumentations patch a dependency as the module loader hands it over, so registration has to happen before that dependency is first imported. `agent/instrumentation.ts`'s `setup` callback ran from a Nitro plugin, and plugin bodies are inlined into the bundled entry while the entry's dependencies are hoisted static imports above them. ESM evaluates every import before any body code, so a driver such as `pg` was already loaded by the time `setup` ran and no spans were produced for it. Reordering the Nitro plugin list does not help: the ordering follows from import hoisting, not from the plugin list. Emit the instrumentation module as its own chunk and import it on the entry's first line, ahead of every hoisted import. `setup` is guarded so it runs once per process even when the module resolves to two instances. Signed-off-by: Matan Kushner <hello@matchai.dev>

- move the bundled load-order test to the scenario tier, which is where the tier docblocks put tests that spawn a subprocess, and drop its first-line assertion as a slower duplicate of the unit test - drop the emitted-chunk reference id: an explicit `fileName` is emitted verbatim, so the constant is the name and the `getFileName` round-trip only added state carried between two hooks - cover the setup-once guard, and clear its `globalThis` latch between tests so it cannot leak into the surrounding cases - restore the OpenTelemetry section's ordering by moving the new auto-instrumentation subsection below the fields it was splitting app-runtime-dependencies located the authored instrumentation module by matching either the global it assigns or the bare dependency name. The second clause also matches the traced dependency's own chunk, which does not run the authored module; it only passed before because the module was inlined into the entry. Match the assigned global alone. Signed-off-by: Matan Kushner <hello@matchai.dev>

vercel · 2026-07-28T21:46:25Z

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Project	Deployment	Actions	Updated (UTC)
eve-docs	Ready	Preview, Comment, Open in v0	Jul 28, 2026 9:46pm

github-actions · 2026-07-28T21:49:37Z

Bundle + Package Summary: `apps/fixtures/weather-agent`

Key takeaways

No notable deltas vs main (9df880e).

Delta vs `main (9df880e)`

Area	Metric	Baseline	Current	Delta
Package	Packed tarball	7.58 MB	7.58 MB	-305 B ✅
Package	Unpacked publish size	28.67 MB	28.67 MB	+5.1 kB ⚠️
Package	Installed footprint	69.79 MB	69.80 MB	+5.1 kB ⚠️
Package	Published files	2846	2850	+4
Package	Installed files	6319	6323	+4
Runtime	Unique function payloads	2	2	0
Runtime	Total function bytes	16.70 MB	16.70 MB	+160 B ⚠️
Runtime	Public routes	11	11	0

Changed function payloads vs main (9df880e) (2)

Function	Status	Baseline	Current	Delta	Route changes
`functions/__server.func`	changed	8.35 MB	8.35 MB	+80 B ⚠️	none
`functions/.well-known/workflow/v1/flow.func`	changed	8.35 MB	8.35 MB	+80 B ⚠️	none

`eve init` install

Metric	Baseline	Current	Delta
Installed footprint	108.19 MB	108.20 MB	+5.1 kB ⚠️
Installed packages	123	123	0
dependencies	4	4	0
devDependencies	2	2	0
Dependency package bytes	42.98 MB	42.99 MB	+5.1 kB ⚠️
devDependency package bytes	5.04 MB	5.04 MB	0 B ➖

Build Metadata

Preset: vercel
Nitro: nitro@3.0.260610-beta
Output directory: apps/fixtures/weather-agent/.vercel/output
Build metadata timestamp: 2026-07-28T21:48:48.104Z
Route aliases: 11 public, 1 internal (12 total aliases)
Vercel routes in config: 14
Severity legend: 🔴 dominant/large, 🟠 notable, 🟡 watch, ⚪ small

Package Drill-Down

Package Details

Package: eve@0.27.11
Package directory: packages/eve
Tarball: 7.58 MB (eve-0.27.11.tgz)
Unpacked payload: 28.67 MB across 2850 published files
Installed footprint: 69.80 MB across 6323 installed files
Installed root package: 27.31 MB
Installed dependencies: 42.48 MB
Runtime dependencies: 2
Peer dependencies: 5 (4 optional)

Installed footprint is measured from an isolated temporary npm install of the packed tarball.

Heavy installed dependencies

eve: 27.31 MB (39.1%)
@rolldown/binding-linux-x64-gnu: 18.96 MB (27.2%)
ai: 6.52 MB (9.3%)
zod: 5.07 MB (7.3%)
nitro: 2.41 MB (3.4%)

Publish payload breakdown

Published file size
🔴 dist/src/compiled/shadcn-registry/index.js       [########################] 13.15 MB 45.9%
🟠 dist/src/compiled/experimental-ai-sdk-code-mo... [###.....................] 1.51 MB 5.3%
🟡 dist/src/compiled/@vercel/sandbox/index.js       [#.......................] 632.5 kB 2.2%
🟡 dist/src/compiled/_chunks/workflow/undici-DWL... [#.......................] 502.4 kB 1.8%
🟡 dist/src/compiled/@chat-adapter/slack/index.js   [#.......................] 440.5 kB 1.5%
🔴 Other published files                            [#######################.] 12.44 MB 43.4%

Installed footprint breakdown

Installed package size
🔴 eve                             [########################] 27.31 MB 39.1%
🔴 @rolldown/binding-linux-x64-gnu [#################.......] 18.96 MB 27.2%
🔴 ai                              [######..................] 6.52 MB 9.3%
🔴 zod                             [####....................] 5.07 MB 7.3%
🟠 nitro                           [##......................] 2.41 MB 3.4%
🟠 undici                          [##......................] 1.86 MB 2.7%
🔴 Other installed packages        [#######.................] 7.67 MB 11.0%

Runtime dependencies (2)

Package	Range	Notes
`nitro`	`3.0.260610-beta`
`undici`	`8.9.0`

Peer dependencies (5)

Package	Range	Notes
`@opentelemetry/api`	`^1.0.0`	optional peer
`ai`	`catalog:`
`braintrust`	`^3.0.0`	optional peer
`just-bash`	`^3.0.0`	optional peer
`microsandbox`	`^0.5.0`	optional peer

eve init install drill-down

`eve init` install details

Command: eve init my-agent
Package manager: npm
Installed footprint: 108.20 MB across 8191 installed files
Installed packages: 123 total (117 transitive-only)
dependencies: 4 direct packages totaling 42.99 MB
devDependencies: 2 direct packages totaling 5.04 MB
Other transitive package files: 60.17 MB

Installed footprint is measured from an isolated temporary eve init my-agent using the current packed eve tarball.

Heavy installed dependencies

@typescript/typescript-linux-x64: 27.95 MB (25.8%)
eve: 27.31 MB (25.2%)
@rolldown/binding-linux-x64-gnu: 18.96 MB (17.5%)
zod: 9.02 MB (8.3%)
ai: 6.52 MB (6.0%)

Installed footprint breakdown

Installed package size
🔴 @typescript/typescript-linux-x64 [########################] 27.95 MB 25.8%
🔴 eve                              [#######################.] 27.31 MB 25.2%
🔴 @rolldown/binding-linux-x64-gnu  [################........] 18.96 MB 17.5%
🔴 zod                              [########................] 9.02 MB 8.3%
🔴 ai                               [######..................] 6.52 MB 6.0%
🟠 @types/node                      [##......................] 2.54 MB 2.4%
🔴 Other installed packages         [##############..........] 15.90 MB 14.7%

dependencies (4)

Package	Range	Installed size	Share
`@vercel/connect`	`0.4.2`	135.8 kB	0.1%
`ai`	`^7.0.38`	6.52 MB	6.0%
`eve`	`file:eve-0.27.11.tgz`	27.31 MB	25.2%
`zod`	`4.4.3`	9.02 MB	8.3%

devDependencies (2)

Package	Range	Installed size	Share
`@types/node`	`24.x`	2.54 MB	2.4%
`typescript`	`7.0.2`	2.50 MB	2.3%

Function Drill-Down

Payload Size Graph

Unique function payload size and share of total
🔴 functions/.well-known/workflow/v1/flow.func     [########################] 8.35 MB 50.0%
🔴 functions/__server.func                         [########################] 8.35 MB 50.0%

Top Function Payloads

🟠 functions/.well-known/workflow/v1/flow.func • 1 public route • 8.35 MB

Metric	Value
Public routes	`/.well-known/workflow/v1/flow`
Runtime	`nodejs24.x`
Handler	`index.mjs`
Payload	8.35 MB
Function files	8.35 MB across 44 files
Traced dependencies	0 B
Signal	🟠 Bundled file `index.mjs` is 2.26 MB (27.1%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                       [#######################.] 2.26 MB 27.1%
🟠 _chunks/runtime-artifacts.mjs   [################........] 1.59 MB 19.0%
🟡 _libs/undici.mjs                [##########..............] 980.5 kB 11.7%
🟡 _chunks/sandbox.mjs             [########................] 768.8 kB 9.2%
🟡 _libs/@ai-sdk/gateway+[...].mjs [####....................] 432.8 kB 5.2%
🟠 Other bundled files             [########################] 2.31 MB 27.7%

🧾 Vercel Config

{
  "handler": "index.mjs",
  "launcherType": "Nodejs",
  "shouldAddHelpers": false,
  "supportsResponseStreaming": true,
  "runtime": "nodejs24.x",
  "maxDuration": "max",
  "experimentalTriggers": [
    {
      "type": "queue/v2beta",
      "topic": "__eve776561746865722d6167656e74_wkf_workflow_*",
      "consumer": "default",
      "retryAfterSeconds": 5,
      "initialDelaySeconds": 0
    }
  ],
  "environment": {
    "WORKFLOW_PRECONDITION_GUARD": "1"
  }
}

🟠 functions/__server.func • 10 public routes, 1 internal alias • 8.35 MB

Metric	Value
Public routes	`/` `/eve/v1/callback/[token]` `/eve/v1/connections/[name]/callback/[token]` `/eve/v1/health` `/eve/v1/info` `/eve/v1/session` `/eve/v1/session/[sessionId]` `/eve/v1/session/[sessionId]/cancel` `/eve/v1/session/[sessionId]/stream` `/eve/v1/session/reset`
Internal aliases	`/__server`
Runtime	`nodejs24.x`
Handler	`index.mjs`
Payload	8.35 MB
Function files	8.35 MB across 44 files
Traced dependencies	0 B
Signal	🟠 Bundled file `index.mjs` is 2.26 MB (27.1%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                       [#######################.] 2.26 MB 27.1%
🟠 _chunks/runtime-artifacts.mjs   [################........] 1.59 MB 19.0%
🟡 _libs/undici.mjs                [##########..............] 980.5 kB 11.7%
🟡 _chunks/sandbox.mjs             [########................] 768.8 kB 9.2%
🟡 _libs/@ai-sdk/gateway+[...].mjs [####....................] 432.8 kB 5.2%
🟠 Other bundled files             [########################] 2.31 MB 27.7%

🧾 Vercel Config

{
  "handler": "index.mjs",
  "launcherType": "Nodejs",
  "shouldAddHelpers": false,
  "supportsResponseStreaming": true,
  "runtime": "nodejs24.x"
}

Build Timing: `e2e/fixtures/agent-tools-sandbox`

This is an informational timing measurement inside eve build, from preflight through publication. Output-size measurement and profile writing are excluded.

Build mode: deployable Vercel build with sandbox template prewarm included.

Build pipeline: 2.00 s -> 1.88 s (-118.2 ms) vs main (9df880e).
Timing is informational: shared GitHub runners are too variable for a hard timing budget.

Detailed phase timings vs `main (9df880e)`

Phase	Baseline	Current	Delta
`extension.check`	1.0 ms	9.3 ms	+8.3 ms
`project.resolve`	0.6 ms	3.5 ms	+2.9 ms
`workspace.create`	0.7 ms	1.4 ms	+0.7 ms
`host.prepare`	238.6 ms	177.1 ms	-61.5 ms
`vercel.service-prefix.resolve`	2.1 ms	2.4 ms	+0.3 ms
`nitro.create`	221.4 ms	188.9 ms	-32.5 ms
`sandbox.prewarm`	245.0 ms	230.9 ms	-14.1 ms
`nitro.cache.prepare`	0.2 ms	0.2 ms	0.0 ms
`nitro.prepare`	0.9 ms	0.7 ms	-0.2 ms
`nitro.public-assets`	0.7 ms	0.7 ms	0.0 ms
`nitro.prerender`	0.5 ms	0.5 ms	0.0 ms
`nitro.bundle`	1.26 s	1.24 s	-22.2 ms
`nitro.cache.write`	0.4 ms	0.4 ms	0.0 ms
`vercel.workflow-function.materialize`	23.5 ms	22.8 ms	-0.7 ms
`agent-summary.emit`	0.5 ms	0.6 ms	+0.1 ms
`nitro.close`	0.1 ms	0.1 ms	0.0 ms
`output.publish`	3.4 ms	3.5 ms	+0.1 ms
`workspace.remove`	2.2 ms	2.5 ms	+0.3 ms

matchai added 2 commits July 27, 2026 18:43

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fix(eve): instrumentation - preload before server dependencies - #1302

fix(eve): instrumentation - preload before server dependencies#1302
AndrewBarba wants to merge 2 commits into
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fix-pg-instrumentation-load-order

AndrewBarba commented Jul 28, 2026

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AndrewBarba commented Jul 28, 2026

Summary

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Validation

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github-actions Bot commented Jul 28, 2026

Bundle + Package Summary: apps/fixtures/weather-agent

Delta vs main (9df880e)

eve init install

Package Details

eve init install details

Payload Size Graph

Top Function Payloads

Build Timing: e2e/fixtures/agent-tools-sandbox

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Bundle + Package Summary: `apps/fixtures/weather-agent`

Delta vs `main (9df880e)`

`eve init` install

`eve init` install details

Build Timing: `e2e/fixtures/agent-tools-sandbox`