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Resources

Photography
Projects
Publications (see also: ESS, ORCID, DBLP, Google Scholar)
Recipes
Repositories (partial mirrors: GitHub, Chaosdorf)
Weblog (Fediverse Microblog: @derf@social.skyshaper.org)
Whatever

Contact

You can reach me by E-Mail (derf@finalrewind.org) and on IRC (derf0 @ OFTC, hackint). My PGP key for E-Mail encryption is 64FE6EC0 55560F9E F13A3044 19E6E524 EBB177BA. I occasionally post stuff on the Fediverse (@derf@social.skyshaper.org).

The remainder of this page duplicates a curated sub-set of projects and the latest blog entries.

Projects

Travel::Routing::DE::DBRIS v0.07
Interface to bahn.de itinerary service

> dbris 'Eichlinghofen H-Bahn, Dortmund' 'Dortmund Hbf'

19.01. 16:51  (00:21)  17:12   .  Bus  S

Bus 440 → Oespel S-Bahnhof, Dortmund
16:51 (+1)  ab  Eichlinghofen H-Bahn, Dortmund
16:56 (+1)  an  Oespel S-Bahnhof, Dortmund

Fußweg 46m  (≈ 3 min.)
S 1 → Dortmund Hbf   .
17:01 (+5)  ab  Dortmund-Oespel  2
17:12 (+2)  an  Dortmund Hbf  7

Travel::Routing::DE::HAFAS v0.10
Interface to HAFAS itinerary services

> hafas 'Eichlinghofen H-Bahn, Dortmund' 'Dortmund Hbf'

00:15        Schw-B HB5  (0:03)  S 1

Schw-B HB5 → Universität S-Bahnhof, Dortmund
21:51  ab  Eichlinghofen H-Bahn, Dortmund
21:55  an  Universität S-Bahnhof, Dortmund

Walk 37m  (approx. 3 minutes)
S 1 → Dortmund Hbf
21:58  ab  Dortmund Universität: 2
22:06  an  Dortmund Hbf: 4

Travel::Routing::DE::EFA v2.24
Interface to EFA itinerary services

> efa Essen Martinstr Düsseldorf Hbf
14:34 ab  Essen Martinstr.: Bstg. 1      Straßenbahn 108      Essen Altenessen Bf Schleife
14:38 an  Essen Hauptbahnhof: Bstg. 1

14:47 ab  Essen Hauptbahnhof: 2          R-Bahn RE11 (RRX)    Düsseldorf Hbf
15:24 an  Düsseldorf Hbf: 10

Travel::Status::DE::DBRIS v0.12
Interface to bahn.de public transit monitors

> dbris-m 'Bochum Hbf'
06:39  ( +7)   ICE 843                             Berlin Hbf  5
06:39  ( +7)   ICE 853                             Berlin Hbf  5
06:51  (+19)       S 1                              Essen Hbf  7
06:37  ( +1)   ICE 527                            München Hbf  3
Zug fährt abweichend mit nur einem Zugteil. Die Wagen 31 - 39 entfallen.

Travel::Status::DE::HAFAS v6.21
Interface to HAFAS public transit monitors

> hafas-m 'Hamburg Dammtor'
13:49  ( +1)  RE 7     Flensburg                  3
13:49  ( +1)  RE 7     Kiel Hbf                   3
13:49         S 5      Buxtehude                  2
13:50  ( +4)  Bus 5    Nedderfeld, Hamburg
13:50         U 1      Ohlstedt, Hamburg

Travel::Status::DE::EFA v3.13
Interface to EFA public transit monitors

> efa-m -s VVO Dresden Hbf
13:40 ( -2)  5      66           Lockwitz
13:41        3      3         .  Wilder Mann
13:44        4      3         .  Coschütz
13:44        6      66           Freital-Deuben
13:46 ( +4)  6      360          Kurort Altenberg Bahnhof
13:46        5      360          Dresden Ammonstraße / Budapester Straße
13:48 ( +1)  1      7         *  Weixdorf
13:51        1      10        .  Tolkewitz
13:52        Gl.10  RE3          Hof Hbf

db-infoscreen
Public Transit Departure Monitor

feh v3.10.3
imlib2 based image viewer

msp430-etv
MSP430 EnergyTrace viewer

travelynx
Public Transit Travel Logger

zlib-deflate-nostdlib
C/C++ embedded decompression library

News

2025-07-05 00:00

Travel::Status::DE::DBRIS v0.12

Travel-Status-DE-DBRIS-0.12.tar.gz (signature)

dbris-m: Fix --(raw-)json for carriage formation requests
Formation::Group: Update carriage name list (patch by Lili Chelsea Urban)
Formation::Group: Update carriage model list (patch by Lili Chelsea Urban)
Formation::Group: Correctly identify LINT 27 and RS 1 trains

2025-07-05 00:00

Travel::Status::DE::IRIS v1.99

Travel-Status-DE-IRIS-1.99.tar.gz (signature)

Deprecation notice: Mention Travel::Status::DE::DBRIS as recommended successor. Travel::Status::DE::HAFAS is no longer a viable alternative.
db-iris: Do not fail if Cache::File is unavailable
Add delay code 27 (Technische Störung am Bus)

2025-06-25 00:00

Travel::Status::DE::HAFAS v6.21

Travel-Status-DE-HAFAS-6.21.tar.gz (signature)

Stop: Handle platform specifiers provided by HAFAS v1 instances

2025-06-21 00:00

Travel::Routing::DE::DBRIS v0.07

Travel-Routing-DE-DBRIS-0.07.tar.gz (signature)

dbris: Add --colour={auto,always,never}

2025-06-20 00:00

Travel::Status::MOTIS v0.03

Travel-Status-MOTIS-0.03.tar.gz (signature)

MOTIS->new: Fix time_zoneparameter not being respected

2025-06-19 00:00

Travel::Status::DE::VRR v3.13

Travel-Status-DE-VRR-3.13.tar.gz (signature)

EFA->new_p: Return $self in case of error so that clients can access place_candidates and name_candidates. This behaviour was already documented, but not implemented.

2025-06-18 00:00

Travel::Status::DE::VRR v3.12

Travel-Status-DE-VRR-3.12.tar.gz (signature)

Departure->id: Include the scheduled departure time. This fixes cases where the trip details (stopseq) endpoint would randomly return yesterday's details or no usable data at all.
efa-m: Trip detail mode now only accepts trip IDs obtained from v3.12+

2025-06-17 00:00

Travel::Status::MOTIS v0.02

Travel-Status-MOTIS-0.02.tar.gz (signature)

motis-m: Fix --json for trip lookups (patch by networkException)
MOTIS: Use v2 API for trip lookups (patch by networkException)
MOTIS: Add time_zone parameter, allowing users to receive times in the specified time_zone rather than the system's local time zone (patch by networkException)
Trip: Add route_text_color accessor (patch by networkException)

2025-06-16 00:00

Travel::Status::DE::VRR v3.11

Travel-Status-DE-VRR-3.11.tar.gz (signature)

efa-m: Show occupancy in trip details
Trip->route: Provide occupancy data

2025-06-15 00:00

Travel::Status::DE::VRR v3.10

Travel-Status-DE-VRR-3.10.tar.gz (signature)

Stop: Add is_cancelled accessor
Add BEG, RVV service definitions
Breaking change: $efa->name_candidates and $efa->place_candidates now return lists of Travel::Status::DE::EFA::Stop objects rather than just strings.