fix(core): Ensure single zod instance across workspace packages

[lucamattiazzi]

Summary

Ensures that zod always has the same version across all packages. Also fixes error message suppression in module import.
Since stable presents the bug, we might want to backport it.

Related Linear tickets, Github issues, and Community forum posts

https://linear.app/n8n/issue/CAT-2822

Review / Merge checklist

• I have seen this code, I have run this code, and I take responsibility for this code.
• PR title and summary are descriptive.
• PR Labeled with Backport to Beta, Backport to Stable, or Backport to v1 (if the PR is an urgent fix that needs to be backported)

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...@n8n/backend-common/src/modules/module-registry.ts	0.00%	2 Missing ⚠️

📢 Thoughts on this report? Let us know!

[cubic-dev-ai]

No issues found across 5 files

Architecture diagram

sequenceDiagram
    participant Registry as ModuleRegistry
    participant Loader as NodeJS import()
    participant Zod as Shared Zod Instance
    participant Mod as Module (Primary/EE)
    participant Err as MissingModuleError

    Note over Registry,Zod: Module Initialization & Zod Singleton Enforcement

    loop for each moduleName
        Registry->>Loader: import(primaryPath)
        
        activate Loader
        Loader->>Zod: Resolve Zod Reference
        Note over Loader,Zod: CHANGED: peerDependencies ensure<br/>workspace-wide singleton instance
        
        alt Primary module exists
            Loader->>Mod: Initialize
            Mod-->>Loader: Module Exports
            Loader-->>Registry: Success (Continue loop)
        else NEW: Error is NOT 'MODULE_NOT_FOUND'
            Loader-->>Registry: Throw logic/syntax error
            Registry->>Err: NEW: Wrap with full stack trace
            Err-->>Registry: Detailed Error
            Note right of Registry: PR fixes error suppression
        else Primary module NOT found
            Loader-->>Registry: MODULE_NOT_FOUND
            deactivate Loader
            
            Registry->>Loader: import(eePath)
            activate Loader
            alt EE module exists
                Loader->>Mod: Initialize
                Mod-->>Loader: Module Exports
                Loader-->>Registry: Success
            else EE module NOT found
                Loader-->>Registry: MODULE_NOT_FOUND
                Registry->>Err: Throw MissingModuleError
            else NEW: EE load fails with logic error
                Loader-->>Registry: Throw logic/syntax error
                Registry->>Err: NEW: Report EE error instead of primary
            end
            deactivate Loader
        end
    end

Loading

[github-actions]

Performance Comparison

Comparing current → latest master → 14-day baseline

PR perf tests not yet enabled. Current = latest master run.

Memory consumption baseline with starter plan resources

Metric	Current	Latest Master	Baseline (avg)	vs Master	vs Baseline	Status
memory-heap-used-baseline	114.81 MB	114.81 MB	114.31 MB (σ 0.45)	+0.0%	+0.4%	⚠️
memory-rss-baseline	281.90 MB	281.90 MB	294.91 MB (σ 43.60)	+0.0%	-4.4%	✅

docker-stats

Metric	Current	Latest Master	Baseline (avg)	vs Master	vs Baseline	Status
docker-image-size-runners	386.00 MB	386.00 MB	390.73 MB (σ 9.55)	+0.0%	-1.2%	✅
docker-image-size-n8n	1269.76 MB	1269.76 MB	1269.76 MB (σ 0.00)	+0.0%	+0.0%	—

Idle baseline with Instance AI module loaded

Metric	Current	Latest Master	Baseline (avg)	vs Master	vs Baseline	Status
instance-ai-heap-used-baseline	186.26 MB	186.26 MB	186.38 MB (σ 0.24)	+0.0%	-0.1%	✅
instance-ai-rss-baseline	380.55 MB	380.55 MB	362.64 MB (σ 22.54)	+0.0%	+4.9%	✅

How to read this table

• Current: This PR's value (or latest master if PR perf tests haven't run)
• Latest Master: Most recent nightly master measurement
• Baseline: Rolling 14-day average from master
• vs Master: PR impact (current vs latest master)
• vs Baseline: Drift from baseline (current vs rolling avg)
• Status: ✅ within 1σ | ⚠️ 1-2σ | 🔴 >2σ regression

[cubic-dev-ai]

1 issue found across 1 file (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="packages/@n8n/backend-common/src/modules/module-registry.ts">

<violation number="1" location="packages/@n8n/backend-common/src/modules/module-registry.ts:99">
P1: Only fall back to EE import when the primary import is actually module-not-found; otherwise unexpected primary import errors can be silently masked.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review, or fix all with cubic.}

[codecov]

Bundle Report

Bundle size has no change ✅

Affected Assets, Files, and Routes:

view changes for bundle: editor-ui-esm

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
assets/worker-*.js	-3.15MB	17.9kB	-99.43%
assets/worker-*.js	3.15MB	3.17MB	17586.03% ⚠️

[ivov]

Consider also pnpm overrides, in case some future transitive dep drags in a different zod version.

[n8n-assistant]

Got released with n8n@2.18.0