ABCDEFGHIJKLMNOPQRSTUVWXYZAAABACADAE
1
ThemeImprovementsScope clarityImpact clarityReachComplexitySavings
tCO2e/year
Δ%MeasuresPrior artSourcePercent
2
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Search
4
Shorter, faster user journeys

Hypothesis: Journeys are shorter when search results are optimal, thanks to better indexing and using SERP features
5
schema.org or similar structured data implementation as a core featureLowLow50%Low2291%
reduction in median time spent on site
0.50%
6
Validation of Wagtail sites’ treatment in Google knowledge graphLowLow50%Medium2291%
reduction in median time spent on site
0.50%
7
Yoast-style content analysis & reporting features for Wagtail sitesLowLow50%Medium2291%
reduction in median time spent on site
0.50%
8
Accessibility checks for common issues also affecting search enginesMediumHigh100%MediumN/A10%
reduction in median accessibility issues on sites
9
Avoiding site visits

Hypothesis: Search users bypass the site when leveraging SERP features.
0.00%
10
Support for Rich Results in CMSMediumLow5%Low231%
reduction in site page views
0.05%
11
Support for Web Stories in CMSMediumLow5%Medium231%
reduction in site page views
https://github.com/torchbox/wagtail-webstories
0.05%
12
Optimised search bot crawling

Hypothesis: Bot indexing of the site will take less resources if optimised
0.00%
13
Better out of the box sitemap generation, including more of the site’s contentsMediumLow5%Low31%
reduction in server-side energy usage
0.01%
14
Redirects awareness, reporting, optimisation to reduce their usage where possibleLowLow1%Low00.1%
reduction in server-side energy usage
0.00%
15
Canonical page awareness, reporting, optimisation to reduce duplicationsLowLow1%Low00.1%
reduction in server-side energy usage
0.00%
16
Web Vitals as sustainability improvements

Hypothesis: Improving sites’ performance web vitals has sustainability value in addition to SEO. Faster sites = better!
0.00%
17
Content analysis with computation of either CWV or proxy "lab" metricsMediumHigh100%MediumN/AN/AAwareness
18
Documentation on common LCP, INP, CLS, FCP issues in WagtailHighHigh10%LowN/AN/AAwareness
19
Cloud infrastructure
0.00%
20
0.00%
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Making the most of cloud CDN capabilities

Hypothesis: CDN-level caching has the most potential to reduce server energy usage
0.00%
22
First-class support like CloudflareMediumLow10%Medium34450%
reduction in server-side energy usage
0.75%
23
Scale-to-zero CMS server on Container infrastructure

Hypothesis: Public-facing site pages can be static, with dynamic server features able to scale to zero when not in use
0.00%
24
Official "Wagtail on Cloud Run" hosting guideMediumLow5%LowN/AAwareness
25
Support for exporting static content for 90+% of CMS featuresMediumHigh10%Medium27540%
reduction in server-side energy usage
0.60%
26
Incremental rebuilds for static contentMediumHigh1%High2840%
reduction in server-side energy usage
0.06%
27
Benchmarking of energy usage - scale-to-zero vs. always-onHighMedium10%LowN/AAwareness
https://www.linkedin.com/pulse/quantifying-greenness-faas-lukasz-mastalerz/
28
Scale-to-zero CMS database

Hypothesis: Public-facing site pages can be static, with database instances scaling to zero when not in use
https://mirror.elements.scaleway.com/
0.00%
29
R&D – Is this possible in GCP? neon.tech vs. AWS Aurora Serverless vs. SQLiteMediumHigh10%Medium34450%
reduction in server-side energy usage
0.75%
30
Scale-to-zero CMS server on FaaS infrastructure

Hypothesis: Public-facing site pages can be static, with dynamic server features as functions able to scale to zero when not in use
0.00%
31
R&D – Is this possible with Wagtail? Does it make any sense compared to Cloud Run?LowLow1%High3450%
reduction in server-side energy usage
https://www.linkedin.com/pulse/quantifying-greenness-faas-lukasz-mastalerz/
0.08%
32
Carbon-aware CMS

Hypothesis: Sites aware of their real-time emissions can adjust their functionality accordingly
0.00%
33
R&D – Carbon-aware CMS app – Does Google offer anything in this space?LowMedium10%High34450%
reduction in server-side energy usage
https://github.com/Green-Software-Foundation/carbon-aware-sdk
https://arxiv.org/abs/2210.04951
0.75%
34
R&D – Carbon-aware background jobs – Does Google offer anything in this space?LowMedium10%High34450%
reduction in server-side energy usage
https://github.com/Green-Software-Foundation/carbon-aware-sdk
https://arxiv.org/abs/2210.04951
0.75%
35
Media
0.00%
36
Responsive imagesHighHigh50%Medium399130%
site image weight reduction
8.70%
37
Optimised Wagtial renditionsHighHigh50%Medium133010%
site image weight reduction
38
AVIF imagesHighHigh50%Medium399130%
site image weight reduction
https://twitter.com/jonsneyers/status/1532014249920319489
8.70%
39
WebP imagesHighHigh50%Medium133010%
site image weight reduction
https://twitter.com/jonsneyers/status/1532014249920319489
2.90%
40
Lossless image optimisation (PNG)HighHigh50%Medium133010%
site image weight reduction
https://cloudinary.com/blog/contemplating-codec-comparisons
2.90%
41
Lossy image optimisation (PNG, MozJPEG)HighHigh50%Medium399130%
site image weight reduction
https://twitter.com/jonsneyers/status/1532014249920319489
8.70%
42
Lazy-loading of imagesMediumHigh50%Low399130%
site image weight reduction
8.70%
43
Optional site images (low-carbon site)MediumHigh1%Low23990%
site image weight reduction
https://github.com/Organic-Basics/ob-low-impact-website
0.52%
44
YouTube lite embedsHighHigh10%Low490%
YouTube embed weight reduction
0.01%
45
0.00%
46
Content
0.00%
47
AccessibilityHighHigh100%MediumN/A
20% improvement in median accessibility issues on sites
48
0.00%
49
CMS features
0.00%
50
Dark modeHighHigh50%Low350%
reduction in screen energy usage for OLED monitors
Awareness?
0.01%
51
Sustainability reporting (page weight)MediumHigh100%LowN/AAwareness
52
Duplicate filesLowLow5%MediumN/ANegligible?
53
Starter templatesMediumHigh1%LowN/A
54
0.00%
55
Data processing
0.00%
56
Background workersMediumMedium50%MediumTBC
Performance only or performance + energy usage? Green compute
57
Template caching for sitesEither Wagtail-custom cache tags or making existing tags aware of previews, draftsHighHigh50%Medium34410%
reduction in server-side energy usage
0.75%
58
Template caching for adminHighHigh100%Low691%
reduction in server-side energy usage
0.15%
59
Wagtail-aware Django debug toolbarHighHigh5%LowN/AAwareness
60
SQL performance optimisationsHighHigh50%Medium34410%
reduction in server-side energy usage
0.75%
61
Alternative Python runtimes (PyPy, Mojo)HighHigh10%Medium34450%
reduction in server-side energy usage
62
Rewrite performance-sensitive code in RustMediumMedium100%Medium68810%
reduction in server-side energy usage
https://github.com/emmett-framework/granian
1.50%
63
0.00%
64
0.00%
65
0.00%
66
0.00%
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