Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
The SIL Model for Writing Systems Computing
Keyboarding
Predictive text
Speech to text
Font features
OpenType
Webfonts
Spell checking
Sorting/Collation
Word/Line breaking
Text Converters
Transliteration�
Unicode
Legacy encodings
The SIL Model for Writing Systems Computing
Keyboarding
Predictive text
Speech to text
Font features
OpenType
Webfonts
Spell checking
Sorting/Collation
Word/Line breaking
Text Converters
Transliteration�
Unicode
Legacy encodings
The SIL Model for Writing Systems Computing
Keyboarding
Predictive text
Speech to text
Font features
OpenType
Webfonts
Spell checking
Sorting/Collation
Word/Line breaking
Text Converters
Transliteration�
Unicode
Legacy encodings
The SIL Model for Writing Systems Computing
Keyboarding
Predictive text
Speech to text
Font features
OpenType
Webfonts
Spell checking
Sorting/Collation
Word/Line breaking
Text Converters
Transliteration�
Unicode
Legacy encodings
The SIL Model for Writing Systems Computing
Keyboarding
Predictive text
Speech to text
Font features
OpenType
Webfonts
Spell checking
Sorting/Collation
Word/Line breaking
Text Converters
Transliteration�
Unicode
Legacy encodings
The SIL Model for Writing Systems Computing
Keyboarding
Predictive text
Speech to text
Font features
OpenType
Webfonts
Spell checking
Sorting/Collation
Word/Line breaking
Text Converters
Transliteration�
Unicode
Legacy encodings
Examples of the kinds of information that can be stored in a locale data record
Keyboard layouts
Keyboard resources
Layout direction
Appropriate fonts
Default feature settings
Sorting order
Transliteration rules
�
Character inventory
Sample texts
SIL
Writing Systems Technology Team
Part of SIL Language Technology�20 people — full and part time�Experience of serving in over 15 countries
Direct support for developers and users�Font development and help�Locale data gathering and stewardship�Academic research and teaching�Liaison to computing and font industries
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Some of 22 font families (inc. 5 new) released in the last couple of years
Scheherazade New, Harmattan, Lateef, Ruwudu, Alkalami (Arabic), Awami Nastaliq
Akatab and Tirra (Tifinagh), Kedebideri (Beria), Abyssinica SIL (Ethiopic)
Narnoor (Gondi), Kanchenjunga (Kirat Rai), Namdhinggo (Limbu), Japa Sans Oriya, Annapurna SIL (Devanagari)
Busra (Khmer), Padauk (Myanmar), Lisu Bosa,�Kay Pho Du (Kayah Li), Nokyung (Dai Banna)
Charis�Gentium
Andika
Doulos SIL
v7 releases
Andika Six
Charis�Gentium
Andika
Doulos SIL
v7 releases
Andika Six
Tighter default line spacing—no Compact versions
More weights!
Oldstyle figures
Charis�Gentium
Andika
Doulos SIL
v7 releases
Andika Six
Charis�Gentium
Andika
Doulos SIL
v7 releases
Andika Six
Capital N Left Hook (changed default)
Diagonal 6 & 9 (Andika)�(cv06 and new cv09)
Many new letters (inc. Unicode 17)
What about Literacy and special versions?
What about subsets?�Can the fonts be smaller?
Charis�Gentium
Andika
Doulos SIL
v7 releases
Andika Six
Where to�get fonts
from SIL
Font Product Sites�Includes all past font versions�(https://software.sil.org/fonts)
SIL Language Technology Font Collection (GFR)�Github Font Repo with all current releases
fonts.languagetechnology.org (FLO)�High performance mirror of Github repo�Can be used as a webfont service�Only for SIL and partners, not general public�External use may be disabled in the future
Factors in future font development by WSTech
Reducing capacity on the WSTech team� Only 7 of team are now full-time� Upcoming retirements, time reductions
Funding challenges� Limits our ability to work with industry� Restricts our influence on big companies
Overall shift in application development� Focus on frameworks based on web techs� Webfonts, variable fonts
Shifting to the most strategic priorities� While maintaining primary core fonts
Graphite retirement
OpenType has replaced Graphite
Removed from most of our fonts
Focus on robust OpenType feature support
Awami Nastaliq still depends on it�Apps that need Nastaliq still need Graphite
Reducing use of TypeTuner
Special variant fonts cause problems
We get requests for fonts we don’t have
People get stuck with missing fonts
Fewer field staff available to help
Need to switch to using OpenType
Pendot
delayed but still in our hopeful plans
Placeholder
Pendot —�Delayed but still in our hopes and dreams
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Q&A
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Discovering problems before they are critical roadblocks
Writing system issues can take years to solve
Push test text completely through a variety�of apps and anticipated publishing paths
Get involved when communities are�making orthography decisions —�Technical issues may be�as important as linguistic ones!
Common problems
Characters that don’t show or look bad (fallback)
White letters on black squares (deprecated)
Letters have the wrong form (use OT feature)
Common problems
Bold seems to be missing in axis-based families
Community wants to use a certain�font but it doesn’t work�(missing letters, accents, ligatures, shaping)�Can you fix it? Can you add a Bold or Italic?�Must be openly licensed (SIL OFL)
Types of OpenType features
Automatic behaviors (always on)� diacritic position, required ligatures
Stylistic Sets (`smcp`, `ss05`, ssnn)� applies alt style to many glyphs� small caps, literacy forms
Character Variants (`cv43`, cvnn)� only one or a few glyphs� alt capital Eng, alt Ogonek
Language-specific (tagged text)� based on language of text� great idea—but poorly supported
Full support
Web apps, CSS-based,
PTXprint, LibreOffice
Automatic behaviors (always on)� diacritic position, required ligatures
Stylistic Sets (`smcp`, `ss05`, ssnn)� applies alt style to many glyphs� small caps, literacy forms
Character Variants (`cv43`, cvnn)� only one or a few glyphs� alt capital Eng, alt Ogonek
Language-specific (tagged text)� based on language of text� great idea—but poorly supported
Partial and limited support
Word,�InDesign
Automatic behaviors (always on)� diacritic position, required ligatures
Stylistic Sets (`smcp`, `ss05`, ssnn)� applies alt style to many glyphs� small caps, literacy forms
Character Variants (`cv43`, cvnn)� only one or a few glyphs� alt capital Eng, alt Ogonek
Language-specific (tagged text)� based on language of text� great idea—but poorly supported
Fonts for mobile apps and websites
How can I use fonts on a website?�Use @font-face to point to a font service (e.g. Google Fonts) or host them yourself
SIL font files are too large—will you provide subset versions for low-bandwidth areas?�No—and subsets are not a realistic option�Current WOFF2 font files are small
Can I use SIL fonts on a mobile device?�Yes! Support needs to be built into app�Fonts can’t be installed and used everywhere�App framework needs to support OpenType
Do you want or need variable fonts?
Where to�go for�help with font or writing system issues
Writing systems forum
LangTech contact page
NEW WSTech site
Email to wstech@sil.org (last resort)
Open Font License site
Font Help Guides
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Q&A
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Language Tags identify writing systems or locales
A language tag is not just a language tag.
lng-Scrp-RE-variants-e-xtensions
The amount of information needed in a "minimal" tag depends on the locale.
Make sure you always use the correct tag!
=
en-Latn
=
en-US
=
en
en-Latn-US
≠
en-Brai
≠
en-GB
≠
en
en-Brai-GB
Where to find langtag information?
How do I find the minimal tag or other Language Tagging data for my locale?
Use langtags.json, downloaded from https://ldml.api.sil.org/langtags.json
Useful fields: tag, full, tags, variants, regions, name, names, localname, localnames, iana, rod, iso639_3, macrolang
See "Langtags Fields" in the links provided at the end of the presentation for descriptions of these fields.
Locale Data in LDML files
Locale Data lives in XML LDML files
Contains: sort orders, character lists, key terms (days, months, languages), localisation support.
CLDR (Common Locale Data Repository)
Run by Unicode. The ultimate authority on locale data. Requires a certain amount of data before a locale can be added.
The SLDR and the LDML API
SLDR (SIL Locale Data Repository)
Run by SIL. Takes CLDR data and adds other locales. Data comes from Ethnologue, the DBL, external contributions, and manual research.
LDML API
SLDR data is accessed through the LDML API. Give a Language Tag, get LDML data from SLDR: http://ldml.api.sil.org/[langtag]
Locale data and YOU
Why should I care?
Tools like Paratext, Flex, and Bloom use the LDML API to provide a starting point for new projects.
SLDR data is a stepping stone for submission to CLDR and wider support for a locale.
How can I help?
Contact us if you have locale data or find an error in the SLDR's existing data!
Finding appropriate fonts for your locale
Language Font Finder
https://lff.api.languagetechnology.org/lang/langtag
Designed for machine to machine communication
Lists font family ids for roles for a language
Gives location of font files for a font family
https://lff.api.languagetechnology.org/family/family
Finding appropriate fonts for your locale
LFF Demo
Finding appropriate fonts for your locale
LFF Demo
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Q&A
Writing Systems Computing
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
LT Webinar September 2025 — SIL Writing Systems Technology
Writing Systems Technical Resources
https://writingsystems.info
Writing Systems Technical Resources
https://writingsystems.info
Writing Systems Technical Resources
https://writingsystems.info
Writing Systems Technical Resources
https://writingsystems.info
Writing Systems Technical Resources
https://writingsystems.info
Writing Systems Technical Resources
https://writingsystems.info/ltweb25
Questions & Answers
Font News and Futures
Font Use and Troubleshooting
Language Tags and Locale Data
Technical Resources
What help do you need from us?
LT Webinar September 2025 — SIL Writing Systems Technology
Q&A