analyze-to-ndjson
Converts Next.js bundle analyzer binary .data files into grep/jq-friendly NDJSON.
Generate the data
pnpm next experimental-analyze --output
This writes binary files to .next/diagnostics/analyze/data/.
Run the converter
node tools/analyze-to-ndjson.mjs
Options:
--input <dir>— source directory (default:.next/diagnostics/analyze/data)--output <dir>— output directory (default:./analyze-ndjson)
Output files
| File | What's in it |
|---|---|
modules.ndjson | Global module registry (id, ident, path) |
module_edges.ndjson | Module dependency graph (from, to, kind: sync/async) |
sources.ndjson | Per-route source tree with sizes and environment flags |
chunk_parts.ndjson | Granular size data: one line per (source, output_file) pair |
output_files.ndjson | Per-route output files with aggregated sizes |
routes.ndjson | Route-level summaries |
Browsing the output
Route overview
# All routes sorted by compressed size
jq -s 'sort_by(-.total_compressed_size)' analyze-ndjson/routes.ndjson
Find large sources
# Top 10 largest sources (deduplicated by full_path)
jq -s '
group_by(.full_path)
| map(max_by(.compressed_size))
| sort_by(-.compressed_size)
| .[0:10]
| .[] | {full_path, compressed_size, size, route}
' analyze-ndjson/sources.ndjson
Client-side JS
# Largest client JS sources
grep '"client":true' analyze-ndjson/sources.ndjson \
| grep '"js":true' \
| jq -s 'sort_by(-.compressed_size) | .[0:10] | .[] | {full_path, compressed_size}'
Module dependencies
# What does module 42 depend on?
grep '"from":42,' analyze-ndjson/module_edges.ndjson | jq .to
# Who depends on module 42?
grep '"to":42,' analyze-ndjson/module_edges.ndjson | jq .from
# Look up a module by path fragment
grep 'react-dom' analyze-ndjson/modules.ndjson | jq '{id, path}'
Output files for a route
# Largest output files for the "/" route
grep '"route":"/"' analyze-ndjson/output_files.ndjson \
| jq -s 'sort_by(-.total_compressed_size) | .[0:10] | .[] | {filename, total_compressed_size, num_parts}'
Directory tree for a route
# Top-level directories for "/"
grep '"route":"/"' analyze-ndjson/sources.ndjson \
| jq 'select(.parent_id == null)'
Feeding to an LLM
The NDJSON files are self-contained — each line has all the context needed to understand it. You can pass a whole file or a filtered subset as context:
# Give an LLM the route summary + the top 20 client sources
cat analyze-ndjson/routes.ndjson > /tmp/context.ndjson
grep '"client":true' analyze-ndjson/sources.ndjson \
| jq -s 'sort_by(-.compressed_size) | .[0:20] | .[]' -c \
>> /tmp/context.ndjson