perf(ui): parallelize chunked chart download fetches

[trivikr]

🔗 Linked issue

N/A

🧭 Context

Longer date ranges and multi-package comparisons pay avoidable network round-trip time because each chunk waits for the previous one to finish. Parallelizing those chunk requests reduces end-to-end chart load time without changing the returned data shape.

📚 Description

This improves chart loading for large npm download date ranges by parallelizing chunked range fetches in useCharts.

Previously, requests larger than the npm downloads API window were split into multiple chunks and fetched sequentially, which made total latency roughly additive across chunks. This change keeps the existing chunking behavior but fetches chunks with bounded concurrency, then merges the results as before.

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Project	Deployment	Actions	Updated (UTC)
npmx.dev	Ready	Preview, Comment	Mar 25, 2026 6:18am

2 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
docs.npmx.dev	Ignored	Preview	Mar 25, 2026 6:18am
npmx-lunaria	Ignored		Mar 25, 2026 6:18am

[codecov]

Codecov Report

❌ Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
app/composables/useCharts.ts	0.00%	3 Missing ⚠️

📢 Thoughts on this report? Let us know!

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 04479310-bfb6-4f81-9050-dc3c0d115061

📥 Commits

Reviewing files that changed from the base of the PR and between eced357 and 2ad2873.

📒 Files selected for processing (1)

• app/composables/useCharts.ts

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📝 Walkthrough

Walkthrough

The fetchDailyRangeChunked() function in the charts composable has been refactored to execute per-chunk fetch requests concurrently rather than sequentially. The function now uses mapWithConcurrency with a concurrency limit of 10 to process chunks in parallel, replacing the previous for...of loop that awaited each chunk individually. The accumulation of daily raw points has changed from incrementally pushing parts into an array to collecting all parts and flattening them in a single operation before merging with mergeDailyPoints(). Public API signatures remain unchanged. The modification spans seven added lines and six removed lines.

🚥 Pre-merge checks | ✅ 1

✅ Passed checks (1 passed)

Check name	Status	Explanation
Description check	✅ Passed	The pull request description clearly explains the performance improvement: parallelizing chunked chart fetches to reduce latency for large date ranges and multi-package comparisons.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[graphieros]

This is awesome, thank you :)