Ben Clifford's tech page

parsl

• Reduce wasted batch job time with task priority: blog (2025-11-08, Parsl blog)
• Automated Testing vs The Enemies of the Release Process: Video (YouTube); Slides (Google Slides) (2025-08-17, US Research Software Association testing workgroup, softwareengineering)
• ZMQ Abuse and Multithreading: Video (YouTube) (2025-09-02, #parsl-hackers, concurrency)
• Pluggable Dependencies: Video (YouTube) (2024-05-28, #parsl-hackers)
• Parsl Monitoring Message Flows: Slides; Video (YouTube) (2025-08-29, ParslFest, observability)
• HTEX Interchange in 3 (or 6) Languages: Slides; Video (YouTube) (2025-08-29, ParslFest, idris2, elixir, rust, languages)
• Plotting Parsl Performance Interactions with R: report (2024-12-10, #parsl-hackers, r, observability)
• Billion Task Parsl: Video (YouTube); Slides (Google Slides) (2024-10-15, #parsl-hackers)
• Codebase stories: A year in the Parsl git repo: Video (YouTube); Slides (Google Slides) (2024-09-26, ParslFest)
• Meta-results: Checkpointing and inspecting errors in Parsl: Video (YouTube); Slides (Google Slides) (2024-08-06, #parsl-hackers)
• Parsl Monitoring Radio Plugins: Video (YouTube) (2024-07-23, #parsl-hackers)
• Parsl File Staging, Then and Now: Video (YouTube); Slides (Google Slides) (2024-04-20, #parsl-hackers)
• The Parsl Task Model vs MPI: Video (YouTube); Slides (Google Slides) (2024-02-20, #parsl-hackers, mpi)
• Parsl Scale-in: Video (YouTube) (2024-02-06, #parsl-hackers)
• Scheduling ParslFest 2024 with Z3: GitHub (2024-09, z3)
• Functional influences on a Python-embedded scientific workflow library: slides (Google Slides) (2024-01-05, Dutch Functional Programming Day, functional)
• Why we can't use multiprocessing in Parsl: slides (Google Slides) (2023-11, #parsl-hackers, concurrency)
• Lifted operators and compositionality: video (YouTube); slides (Google Slides); follow-on blog post (2023-10-03, #parsl-hackers)
• Code and Community: slides (2023-09-19, ParslFest)
• 10000 to 1 (tasks per second) - How can some Parsl runs be so slow?: slides; video (YouTube) (2023-09-10, ParslFest)
• Same Object, Different Process - Serialization in Parsl and Python: slides (Google Slides); video (diode.zone); video (YouTube) (2023-04-13, #parsl-hackers, python)
• Multicomponent performance monitoring: slides; video (2022-09-14, ParslFest, observability)
• Understanding workflow progress with Parsl monitoring: video (2021-10-28, ParslFest, observability)
• Dependencies beyond the DAG: zoom video (2020-10-08, ParslFest)

haskell

• the Num typeclass: slides (2014-02-26, London Haskell, numbers)
• Commandline Tools in Haskell: Slides (2019-05-29, London Haskell, commandline)
• LSC todaybot using extensible effects in Haskell: slides (2016-02-24, London Haskell, effects, reddit, london)
• An awkward interaction between lazy ByteStrings and a misbehaving (non-)transparent HTTP middlebox: slides (2015-05-27, London Haskell, tcpip, http)
• acme-smuggler: GitHub; Presentation slides (2016-12, functional)
• A Horrified Haskeller's Descent Into Python Gradual Static Typing: zoom video; slides (2021-03-09, Berlin Functional Programmers, python, types)
• London Haskell Christmas Pub Quiz 2019: index (2019-12-10, London Haskell, london, quiz)
• London Haskell Christmas Pub Quiz 2018: quiz (2018-12-05, London Haskell, london, quiz)
• Blog series: Build A Crap Webform in Haskell in 28 Days: First post (2018-02-01)
• Article series: 12 Monads of Christmas: First article; overview video at London Haskell (2016-12-21)
• Practical Haskell Systems Issues at Beautiful Destinations: video (2016-10-25)
• Parsing Stuff in Haskell: video (2013-01-23, London Haskell)
• lsdupes - a unix command to find files with identical content: index (2010-04-28)
• Roman numerals in Java and Haskell: notes (2010-02-04, numbers, java)

raspberrypi

• Mastodon, the Fediverse and a Camera Bot: video (youtube) (2023-01-31, Raspberry Pint, fediverse)
• Refugees, Codepages and Thermal Paper: video; slides (2022-09-27, Raspberry Pint, charset)
• A Postcard from Electromagnetic Field 2022 lightning talk: zoom video; slides (2022-06-28, Raspberry Pint, camp)
• An RS-232 level shifter board for Raspberry Pi: video (2019-09-24, Raspberry Pint, bbcmicro, rs232)
• BBC Micro + Raspberry Pi: video (2019-07-31, Raspberry Pint, bbcmicro, rs232)
• Alternative programming languages for Raspberry Pi: video (2019-01-29, Raspberry Pint, languages)
• A Postcard from Electromagnetic Field 2018: video; slides (2018-09-25, Raspberry Pint, camp)
• Raspberry Pi Spycam using OpenCV: video (2018-06-26, Raspberry Pint, vision)
• Erlang + Raspberry Pi Sous Vide Cooker: video (2018-02-27, Raspberry Pint, food, erlang)
• Raspberry Pi / Arduino / ESP 8266: video (2017-11-28, Raspberry Pint, esp8266, attiny85)
• NTP and MSF radio clocks for Raspberry Pi: video; slides (2017-07-24, Raspberry Pint, time)

led

• Patterns for AdaFruit LED Goggles: Gallery; source code (github) (2017-06-16, attiny85)
• Some of my LED projects: zoom video (2021-07-27, Raspberry Pint)
• Rainbow maths: zoom video (2020-10-27, Raspberry Pint)
• Spiral LED wall clock project: GitHub (2020-08-15)
• Persistence of Vision bike wheel: zoom video; slides (2020-04-06, Raspberry Pint, bike)

python

• The Ghost of Distant Objects: Conference talk abstract; Video (YouTube); Slides (Google Slides) (2024-04, PyCon LT, pickle)
• Pickle: everybody hates it, everybody uses it: Slides (Google slides) (2024-06, PyBerlin, pickle)
• Beyond Values: web page (2023-04-30)
• Python Gradual Typing - the Good, the Bad and the Ugly: Video (YouTube); Slides (2022-03-11, BOBKonf, types)
• Breaking recursion in Python and fix-ing it back up again: README (2021-11-07)

scientificworkflow

• Swift vs Open Provenance Model technical notes: on hierachical processes, PDF; on collections, PDF (2010-04-28, provenance)
• From PCs to clusters to grids - a one-hour talk on programming applications for clusters and grids using a loosely coupled file based approach, which I gave at the University of Johannesburg in April 2009: slides, PDF; slides, OpenOffice (2009-04-15)
• SwiftScript presentation for the Software Technology Colloqium at uu.nl: slides (2010-02-16, language)

fpga

• ShittyCPU40: Building a hobby CPU: slides; video; github (2022-04-23, Raspberry Pint)
• FPGAs: slides; GitHub repo (2020-01-29, Raspberry Pint)

history

• Official Railway Map of London and its Environs, 1899: video (diode.zone); map (Harvard Map Collection) (2020-11-20, transport, map)
• IPv6 and Internet History: slides (PDF); slides (Google); video (2021-10-27, Raspberry Pint, ipv6)

Misc

• Ownership in the Type System: slides (2018-06, London Haskell, rust, types)
• notes on a software assisted transport-modes pub crawl around London in 2017: notes (2021-09-12, transport, london)
• Filesystems: zoom video; slides (2021-02-23, Raspberry Pint, filesystems)
• A map of Berlin with my bike rides and walks overlaid: map (2021-01-24, map, bike, berlin)
• Links to videos of talks I've given: index (2021-12-28)
• Current and voltage GPIO maths lesson: zoom video (2020-06-30, Raspberry Pint, electronics)
• snaprotate - deletes old rsync-based snapshots, using a combinator lanuage embedded in Haskell: index (2010-05-07)
• Blog: benc technical blog: blog index (2010-02-27)
• My extra-long bash prompt: index (2010-02-24)
• Notes on maildir conventions: notes (2010-02-04)
• SMS PDU decoder for Sony Ericsson phones: index (2010-01-18, telephony)
• 26c3-ddc - a Haskell EDSL for controlling the blinkenlights at the 26th Chaos Communications Congress: index (2010-01-14)
• JiniGrid - a taskfarm service for Jini: report (2000-09, java, jini, grid)

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