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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
90
GRADE
A
FIX
0
REVIEW
3
PASS
9
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
99
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
98
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

588 ms

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

769 ms

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

0 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.001

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

588 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

769 ms

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
14
9 PASS 3 REVIEW
B
Page Weight Budget
1.4 MB transferred, 58 requests
REVIEW
1.4 MB transferred, 58 requests
Info::
Page weighs 2.0 MB (1.4 MB transferred)
Info::
Fonts are 347 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 347 KB
Info::
58 HTTP requests
Info::
Estimated 0.29 g CO2 per page load
1.4 MB / 2.4 MB budget
1.4 MB transferred
58 requests
0.29 g CO2 per page load
Images 874.8 KiB 62%
Fonts 347.4 KiB 25%
JavaScript 129.0 KiB 9%
CSS 30.4 KiB 2%
HTML 10.5 KiB 1%
Other 8.0 KiB 1%
Other 989 B 0%
Other 230 B 0%
0 2.4 MB 4.9 MB
Under budget

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

C
Image Optimization
Action
35 images, 0 KB saveable
REVIEW
35 images, 0 KB saveable
Warning::
https://www.apache.org/images/linkedin-icon.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/bluesky-icon.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/youtube-icon.svg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/asflogo_horizontal_c... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/slack-icon.svg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/asf_logo_full_horizo... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/github-mark-white.sv... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/x-icon.svg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.apache.org/images/mastodon-icon.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
35 images 875 KB
0 oversized -0 KB
27 legacy format
9 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Third-Party Impact
5% third-party, 0 ms blocking
PASS
5% third-party, 0 ms blocking
Info::
Third-party code accounts for 5% of page weight (66.1 KiB of 1.4 MiB)
Info::
Third-party blocking time is low (0 ms)
95%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
JS Execution Cost
442ms total JS execution
PASS
442ms total JS execution
Warning::
https://www.apache.org/: 275ms CPU time
Info::
Unattributable: 167ms CPU time
Info::
Third-party scripts: 167ms (38% of total)

Main Thread Breakdown

Other 46% Style & Layout 24% Script Evaluation 14% Rendering 9% Script Parsing & Compilation 4% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://www.apache.org/275ms31ms4ms1st
Unattributable167ms5ms0ms3rd
A+
Font Loading
6 fonts (347 KB)
PASS
6 fonts (347 KB)
Info::
6 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

6

347 KB total

Render-blocking

0

of 6

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 588 ms LCP 769 mshttps://www.apache.org/css/OpenSans-Bold.ttfOpenSans-Bold.ttf https://www.apache.org/css/OpenSans-Bold.ttf — 74.5 KiB — 0 ms — font-display: swaphttps://www.apache.org/fonts/glyphicons-halflings-regular.woff2glyphicons-halflings-re... https://www.apache.org/fonts/glyphicons-halflings-regular.woff2 — 18.3 KiB — 0 ms — font-display: swaphttps://www.apache.org/css/Montserrat-ExtraBold.ttfMontserrat-ExtraBold.ttf https://www.apache.org/css/Montserrat-ExtraBold.ttf — 145.2 KiB — 0 ms — font-display: swaphttps://www.apache.org/css/OpenSans-Regular.ttfOpenSans-Regular.ttf https://www.apache.org/css/OpenSans-Regular.ttf — 76.7 KiB — 0 ms — font-display: swaphttps://www.apache.org/css/JTUHjIg1_i6t8kCHKm4532VJOt5-QNFgpCu173w5aX8.ttfJTUHjIg1_i6t8kCHKm4532V... https://www.apache.org/css/JTUHjIg1_i6t8kCHKm4532VJOt5-QNFgpCu173w5aX8.ttf — 16.1 KiB — 0 ms — font-display: swaphttps://www.apache.org/css/JTUHjIg1_i6t8kCHKm4532VJOt5-QNFgpCs16Hw5aX8.ttfJTUHjIg1_i6t8kCHKm4532V... https://www.apache.org/css/JTUHjIg1_i6t8kCHKm4532VJOt5-QNFgpCs16Hw5aX8.ttf — 16.6 KiB — 0 ms — font-display: swap
OpenSans-Bold.ttf ttf swap
Size 74 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
glyphicons-halflings-re... woff2 swap
Size 18 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Montserrat-ExtraBold.ttf ttf swap
Size 145 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
OpenSans-Regular.ttf ttf swap
Size 77 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
JTUHjIg1_i6t8kCHKm4532V... ttf swap
Size 16 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
JTUHjIg1_i6t8kCHKm4532V... ttf swap
Size 17 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)

Fixing the unchecked items could save ~171 KB and ~342 ms

A
JS Bundles
6 scripts, 38 KB unused
PASS
6 scripts, 38 KB unused
Warning::
https://analytics.apache.org/matomo.js: 38 KB unused (59%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.apache.org/js/bootstrap.js: unminified — 4 KB could be saved
Info::
Total unused JavaScript: 38 KB
38 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://analytics.apache.org/matomo.js66 KB38 KB (59%)✓3rd
https://www.apachecon.com/event-images/snippet.js0 KB—✓3rd
https://www.apache.org/_pagefind/pagefind-ui.js22 KB—✓1st
https://www.apache.org/js/jquery.min.js30 KB—✓1st
https://www.apache.org/js/bootstrap.js11 KB—✗1st
https://www.apache.org/js/slideshow.js1 KB—✓1st

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
HTTP Caching
max-age=3600 (1 hour)
PASS
max-age=3600 (1 hour)
Info::
Cache-Control header is set
Got: max-age=3600
Info::
Effective TTL: 1 hour (max-age=3600)
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present
Cache-Control

max-age=3600

DirectiveValueMeaning
max-age3600Cache for 1 hour
Effective TTL: 3600 seconds
Network Waterfall
58 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
38% of JavaScript execution is third-party
First-party Third-party 167ms · 0KB · €2/mo
Unattributable
Other
Optional
Execution 167ms
Transfer 0 KB
Monthly Cost €2/mo

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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