Credits
MRTdoku is a fan-made daily puzzle. The station dataset, the game mechanics, and the design borrow from public sources — listed and attributed below.
Station dataset
Station codes, line memberships, geographic coordinates, and opening-date references in the puzzle are derived from data published by the Singapore Land Transport Authority on LTA DataMall.
Contains information from LTA DataMall, accessed on 2026-05-08 from https://datamall.lta.gov.sg, made available under the terms of the Singapore Open Data Licence version 1.0.
Cross-references
Station etymology, name romanisation, and historical opening-date cross-references are derived from Wikipedia and Wikidata. Wikipedia content is available under the Creative Commons Attribution-ShareAlike 4.0 license; Wikidata structured data is released under the CC0 1.0 Public Domain Dedication. The initial 30-station set was assembled on 2026-05-07; the extension to 181 stations was assembled on 2026-05-08.
Inspirations
The puzzle format takes its name and 3×3 grid from Métrodoku (Paris RATP) and Tubedoku (London TfL). MRTdoku is an independent Singapore-flavoured adaptation and is not affiliated with either project.
Typography
Display copy is set in Space Grotesk by Florian Karsten; codes, scores, and UI labels in IBM Plex Mono by IBM; hand-written annotations in Caveat by Pablo Impallari. All three fonts are loaded from Google Fonts and are licensed under the SIL Open Font License.
Trademarks and affiliation
Not affiliated with, endorsed by, or sponsored by the Land Transport Authority of Singapore, SMRT Trains Ltd, or SBS Transit Ltd. “MRT”, MRT/LRT line names, and line colors are referenced under fair-use principles for an educational fan puzzle. No claim of official status is made or intended.