• We are trying to put together a schedule for one week
• Each day has some set of work shifts that need to be staffed
• Each shift must be staffed with exactly one worker
• The shift schedule is known beforehand, and the workers each declare their preferences beforehand: they mark each shift in the week as one of:
  • PREFERRED (if they want to be scheduled on that shift)
  • NEUTRAL
  • DISFAVORED (if they don't love that shift)
  • REFUSED (if they absolutely cannot work that shift)

#!/usr/bin/python3
import sys
import os
import re
def report_solution_to_console(vars):
    for w in days_of_week:
        annotation = ''
        if human_annotate is not None:
            for s in shifts.keys():
                m = re.match(rf' w  - ', s)
                if not m: continue
                if vars[human_annotate][s].value():
                    annotation = f" ( human_annotate  SCHEDULED)"
                    break
            if not len(annotation):
                annotation = f" ( human_annotate  OFF)"
        print(f" w annotation ")
        for s in shifts.keys():
            m = re.match(rf' w  - ', s)
            if not m: continue
            annotation = ''
            if human_annotate is not None:
                annotation = f" ( human_annotate   shifts[s][human_annotate] )"
            print(f"    ----  s[m.end():] annotation ")
            for h in humans:
                if vars[h][s].value():
                    print(f"          h  ( shifts[s][h] )")
def report_solution_summary_to_console(vars):
    print("\nSUMMARY")
    for h in humans:
        print(f"--  h ")
        print(f"   benefit:  benefits[h].value():.3f ")
        counts = dict()
        for a in availabilities:
            counts[a] = 0
        for s in shifts.keys():
            if vars[h][s].value():
                counts[shifts[s][h]] += 1
        for a in availabilities:
            print(f"    counts[a]   a ")
human_annotate = None
days_of_week = ('SUNDAY',
                'MONDAY',
                'TUESDAY',
                'WEDNESDAY',
                'THURSDAY',
                'FRIDAY',
                'SATURDAY')
humans = ['ALICE', 'BOB',
          'CAROL', 'DAVID', 'EVE', 'FRANK', 'GRACE', 'HEIDI', 'IVAN', 'JUDY']
shifts =  'SUNDAY - SANDING 9:00 AM - 4:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'DISFAVORED',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'JUDY':  'NEUTRAL' ,
          'WEDNESDAY - SAWING 7:30 AM - 2:30 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'EVE':   'REFUSED',
           'JUDY':  'REFUSED' ,
          'THURSDAY - SANDING 9:00 AM - 4:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'PREFERRED',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED' ,
          'SATURDAY - SAWING 7:30 AM - 2:30 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'FRANK': 'PREFERRED',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'EVE':   'REFUSED',
           'JUDY':  'REFUSED',
           'GRACE': 'REFUSED' ,
          'SUNDAY - SAWING 9:00 AM - 4:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED' ,
          'MONDAY - SAWING 9:00 AM - 4:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'PREFERRED',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED' ,
          'TUESDAY - SAWING 9:00 AM - 4:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'NEUTRAL',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED' ,
          'WEDNESDAY - PAINTING 7:30 AM - 2:30 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'EVE':   'REFUSED',
           'JUDY':  'REFUSED',
           'DAVID': 'REFUSED' ,
          'THURSDAY - SAWING 9:00 AM - 4:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'PREFERRED',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED' ,
          'FRIDAY - SAWING 9:00 AM - 4:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'DAVID': 'PREFERRED',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'PREFERRED',
           'IVAN':  'PREFERRED',
           'JUDY':  'DISFAVORED',
           'HEIDI': 'REFUSED' ,
          'SATURDAY - PAINTING 7:30 AM - 2:30 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'FRANK': 'PREFERRED',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'EVE':   'REFUSED',
           'JUDY':  'REFUSED',
           'GRACE': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'SUNDAY - PAINTING 9:45 AM - 4:45 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'MONDAY - PAINTING 9:45 AM - 4:45 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'PREFERRED',
           'IVAN':  'PREFERRED',
           'JUDY':  'NEUTRAL',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'TUESDAY - PAINTING 9:45 AM - 4:45 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'NEUTRAL',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'WEDNESDAY - SANDING 9:45 AM - 4:45 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'DAVID': 'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'JUDY':  'NEUTRAL',
           'EVE':   'REFUSED' ,
          'THURSDAY - PAINTING 9:45 AM - 4:45 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'NEUTRAL',
           'IVAN':  'PREFERRED',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'FRIDAY - PAINTING 9:45 AM - 4:45 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'PREFERRED',
           'FRANK': 'PREFERRED',
           'GRACE': 'PREFERRED',
           'IVAN':  'PREFERRED',
           'JUDY':  'DISFAVORED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'SATURDAY - SANDING 9:45 AM - 4:45 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'DAVID': 'PREFERRED',
           'FRANK': 'PREFERRED',
           'HEIDI': 'DISFAVORED',
           'IVAN':  'PREFERRED',
           'EVE':   'REFUSED',
           'JUDY':  'REFUSED',
           'GRACE': 'REFUSED' ,
          'SUNDAY - PAINTING 11:00 AM - 6:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'PREFERRED',
           'IVAN':  'NEUTRAL',
           'JUDY':  'NEUTRAL',
           'DAVID': 'REFUSED' ,
          'MONDAY - PAINTING 12:00 PM - 7:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'PREFERRED',
           'IVAN':  'NEUTRAL',
           'JUDY':  'NEUTRAL',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'TUESDAY - PAINTING 12:00 PM - 7:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'NEUTRAL',
           'HEIDI': 'REFUSED',
           'JUDY':  'REFUSED',
           'DAVID': 'REFUSED' ,
          'WEDNESDAY - PAINTING 12:00 PM - 7:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'NEUTRAL',
           'JUDY':  'PREFERRED',
           'EVE':   'REFUSED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'THURSDAY - PAINTING 12:00 PM - 7:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'NEUTRAL',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'FRIDAY - PAINTING 12:00 PM - 7:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'NEUTRAL',
           'JUDY':  'DISFAVORED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'SATURDAY - PAINTING 12:00 PM - 7:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'NEUTRAL',
           'FRANK': 'NEUTRAL',
           'IVAN':  'NEUTRAL',
           'JUDY':  'DISFAVORED',
           'EVE':   'REFUSED',
           'HEIDI': 'REFUSED',
           'GRACE': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'SUNDAY - SAWING 12:00 PM - 7:00 PM':
           'ALICE': 'PREFERRED',
           'BOB':   'PREFERRED',
           'CAROL': 'NEUTRAL',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'NEUTRAL',
           'JUDY':  'PREFERRED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'MONDAY - SAWING 2:00 PM - 9:00 PM':
           'ALICE': 'PREFERRED',
           'BOB':   'PREFERRED',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'TUESDAY - SAWING 2:00 PM - 9:00 PM':
           'ALICE': 'PREFERRED',
           'BOB':   'PREFERRED',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'HEIDI': 'REFUSED',
           'JUDY':  'REFUSED',
           'DAVID': 'REFUSED' ,
          'WEDNESDAY - SAWING 2:00 PM - 9:00 PM':
           'ALICE': 'PREFERRED',
           'BOB':   'PREFERRED',
           'CAROL': 'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'EVE':   'REFUSED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'THURSDAY - SAWING 2:00 PM - 9:00 PM':
           'ALICE': 'PREFERRED',
           'BOB':   'PREFERRED',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'HEIDI': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'FRIDAY - SAWING 2:00 PM - 9:00 PM':
           'ALICE': 'PREFERRED',
           'BOB':   'PREFERRED',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'HEIDI': 'REFUSED',
           'JUDY':  'REFUSED',
           'DAVID': 'REFUSED' ,
          'SATURDAY - SAWING 2:00 PM - 9:00 PM':
           'ALICE': 'PREFERRED',
           'BOB':   'PREFERRED',
           'CAROL': 'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'EVE':   'REFUSED',
           'HEIDI': 'REFUSED',
           'GRACE': 'REFUSED',
           'DAVID': 'REFUSED' ,
          'SUNDAY - PAINTING 12:15 PM - 7:15 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'PREFERRED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'NEUTRAL',
           'DAVID': 'REFUSED' ,
          'MONDAY - PAINTING 2:00 PM - 9:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'DAVID': 'REFUSED' ,
          'TUESDAY - PAINTING 2:00 PM - 9:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'REFUSED',
           'DAVID': 'REFUSED' ,
          'WEDNESDAY - PAINTING 2:00 PM - 9:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'EVE':   'REFUSED',
           'DAVID': 'REFUSED' ,
          'THURSDAY - PAINTING 2:00 PM - 9:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'DAVID': 'REFUSED' ,
          'FRIDAY - PAINTING 2:00 PM - 9:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'DISFAVORED',
           'EVE':   'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'GRACE': 'NEUTRAL',
           'HEIDI': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'REFUSED',
           'DAVID': 'REFUSED' ,
          'SATURDAY - PAINTING 2:00 PM - 9:00 PM':
           'ALICE': 'NEUTRAL',
           'BOB':   'NEUTRAL',
           'CAROL': 'DISFAVORED',
           'FRANK': 'NEUTRAL',
           'HEIDI': 'NEUTRAL',
           'IVAN':  'DISFAVORED',
           'JUDY':  'DISFAVORED',
           'EVE':   'REFUSED',
           'GRACE': 'REFUSED',
           'DAVID': 'REFUSED' 
availabilities = ['PREFERRED', 'NEUTRAL', 'DISFAVORED']
import pulp
prob = pulp.LpProblem("Scheduling", pulp.LpMaximize)
vars = pulp.LpVariable.dicts("Assignments",
                             (humans, shifts.keys()),
                             None,None, # bounds; unused, since these are binary variables
                             pulp.LpBinary)
# Everyone works at least 2 shifts
Nshifts_min = 2
for h in humans:
    prob += (
        pulp.lpSum([vars[h][s] for s in shifts.keys()]) >= Nshifts_min,
        f" h  works at least  Nshifts_min  shifts",
    )
# each shift is ~ 8 hours, so I limit everyone to 40/8 = 5 shifts
Nshifts_max = 5
for h in humans:
    prob += (
        pulp.lpSum([vars[h][s] for s in shifts.keys()]) <= Nshifts_max,
        f" h  works at most  Nshifts_max  shifts",
    )
# all shifts staffed and not double-staffed
for s in shifts.keys():
    prob += (
        pulp.lpSum([vars[h][s] for h in humans]) == 1,
        f" s  is staffed",
    )
# each human can work at most one shift on any given day
for w in days_of_week:
    for h in humans:
        prob += (
            pulp.lpSum([vars[h][s] for s in shifts.keys() if re.match(rf' w  ',s)]) <= 1,
            f" h  cannot be double-booked on  w "
        )
#### Some explicit constraints; as an example
# DAVID can't work any PAINTING shift and is off on Thu and Sun
h = 'DAVID'
prob += (
    pulp.lpSum([vars[h][s] for s in shifts.keys() if re.search(r'- PAINTING',s)]) == 0,
    f" h  can't work any PAINTING shift"
)
prob += (
    pulp.lpSum([vars[h][s] for s in shifts.keys() if re.match(r'THURSDAY SUNDAY',s)]) == 0,
    f" h  is off on Thursday and Sunday"
)
# Do not assign any "REFUSED" shifts
for s in shifts.keys():
    for h in humans:
        if shifts[s][h] == 'REFUSED':
            prob += (
                vars[h][s] == 0,
                f" h  is not available for  s "
            )
# Objective. I try to maximize the "happiness". Each human sees each shift as
# one of:
#
#   PREFERRED
#   NEUTRAL
#   DISFAVORED
#   REFUSED
#
# I set a hard constraint to handle "REFUSED", and arbitrarily, I set these
# benefit values for the others
benefit_availability = dict()
benefit_availability['PREFERRED']  = 3
benefit_availability['NEUTRAL']    = 2
benefit_availability['DISFAVORED'] = 1
# Not used, since this is a hard constraint. But the code needs this to be a
# part of the benefit. I can ignore these in the code, but let's keep this
# simple
benefit_availability['REFUSED' ] = -1000
benefits = dict()
for h in humans:
    benefits[h] = \
        pulp.lpSum([vars[h][s] * benefit_availability[shifts[s][h]] \
                    for s in shifts.keys()])
benefit_total = \
    pulp.lpSum([benefits[h] \
                for h in humans])
prob += (
    benefit_total,
    "happiness",
)
prob.solve()
if pulp.LpStatus[prob.status] == "Optimal":
    report_solution_to_console(vars)
    report_solution_summary_to_console(vars)

benefit_availability = dict()
benefit_availability['PREFERRED']  = 3
benefit_availability['NEUTRAL']    = 2
benefit_availability['DISFAVORED'] = 1
benefits = dict()
for h in humans:
    benefits[h] = \
        pulp.lpSum([vars[h][s] * benefit_availability[shifts[s][h]] \
                    for s in shifts.keys()])
benefit_total = \
    pulp.lpSum([benefits[h] \
                for h in humans])

....
Result - Optimal solution found
Objective value:                108.00000000
Enumerated nodes:               0
Total iterations:               0
Time (CPU seconds):             0.01
Time (Wallclock seconds):       0.01
Option for printingOptions changed from normal to all
Total time (CPU seconds):       0.02   (Wallclock seconds):       0.02
SUNDAY
    ---- SANDING 9:00 AM - 4:00 PM
         EVE (PREFERRED)
    ---- SAWING 9:00 AM - 4:00 PM
         IVAN (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM
         FRANK (PREFERRED)
    ---- PAINTING 11:00 AM - 6:00 PM
         HEIDI (PREFERRED)
    ---- SAWING 12:00 PM - 7:00 PM
         ALICE (PREFERRED)
    ---- PAINTING 12:15 PM - 7:15 PM
         CAROL (PREFERRED)
MONDAY
    ---- SAWING 9:00 AM - 4:00 PM
         DAVID (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM
         IVAN (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM
         GRACE (PREFERRED)
    ---- SAWING 2:00 PM - 9:00 PM
         ALICE (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM
         HEIDI (NEUTRAL)
TUESDAY
    ---- SAWING 9:00 AM - 4:00 PM
         DAVID (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM
         EVE (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM
         FRANK (NEUTRAL)
    ---- SAWING 2:00 PM - 9:00 PM
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM
         HEIDI (NEUTRAL)
WEDNESDAY
    ---- SAWING 7:30 AM - 2:30 PM
         DAVID (PREFERRED)
    ---- PAINTING 7:30 AM - 2:30 PM
         IVAN (PREFERRED)
    ---- SANDING 9:45 AM - 4:45 PM
         FRANK (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM
         JUDY (PREFERRED)
    ---- SAWING 2:00 PM - 9:00 PM
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM
         ALICE (NEUTRAL)
THURSDAY
    ---- SANDING 9:00 AM - 4:00 PM
         GRACE (PREFERRED)
    ---- SAWING 9:00 AM - 4:00 PM
         CAROL (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM
         EVE (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM
         JUDY (PREFERRED)
    ---- SAWING 2:00 PM - 9:00 PM
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM
         ALICE (NEUTRAL)
FRIDAY
    ---- SAWING 9:00 AM - 4:00 PM
         DAVID (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM
         FRANK (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM
         GRACE (NEUTRAL)
    ---- SAWING 2:00 PM - 9:00 PM
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM
         HEIDI (NEUTRAL)
SATURDAY
    ---- SAWING 7:30 AM - 2:30 PM
         CAROL (PREFERRED)
    ---- PAINTING 7:30 AM - 2:30 PM
         IVAN (PREFERRED)
    ---- SANDING 9:45 AM - 4:45 PM
         DAVID (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM
         FRANK (NEUTRAL)
    ---- SAWING 2:00 PM - 9:00 PM
         ALICE (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM
         BOB (NEUTRAL)
SUMMARY
-- ALICE
   benefit: 13.000
   3 PREFERRED
   2 NEUTRAL
   0 DISFAVORED
-- BOB
   benefit: 14.000
   4 PREFERRED
   1 NEUTRAL
   0 DISFAVORED
-- CAROL
   benefit: 9.000
   3 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- DAVID
   benefit: 15.000
   5 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- EVE
   benefit: 9.000
   3 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- FRANK
   benefit: 13.000
   3 PREFERRED
   2 NEUTRAL
   0 DISFAVORED
-- GRACE
   benefit: 8.000
   2 PREFERRED
   1 NEUTRAL
   0 DISFAVORED
-- HEIDI
   benefit: 9.000
   1 PREFERRED
   3 NEUTRAL
   0 DISFAVORED
-- IVAN
   benefit: 12.000
   4 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- JUDY
   benefit: 6.000
   2 PREFERRED
   0 NEUTRAL
   0 DISFAVORED

Objective value:                108.00000000
Enumerated nodes:               0
Total iterations:               0
Time (CPU seconds):             0.01
Time (Wallclock seconds):       0.01
Option for printingOptions changed from normal to all
Total time (CPU seconds):       0.01   (Wallclock seconds):       0.02
SUNDAY (JUDY OFF)
    ---- SANDING 9:00 AM - 4:00 PM (JUDY NEUTRAL)
         EVE (PREFERRED)
    ---- SAWING 9:00 AM - 4:00 PM (JUDY PREFERRED)
         IVAN (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM (JUDY PREFERRED)
         FRANK (PREFERRED)
    ---- PAINTING 11:00 AM - 6:00 PM (JUDY NEUTRAL)
         HEIDI (PREFERRED)
    ---- SAWING 12:00 PM - 7:00 PM (JUDY PREFERRED)
         ALICE (PREFERRED)
    ---- PAINTING 12:15 PM - 7:15 PM (JUDY NEUTRAL)
         CAROL (PREFERRED)
MONDAY (JUDY OFF)
    ---- SAWING 9:00 AM - 4:00 PM (JUDY PREFERRED)
         DAVID (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM (JUDY NEUTRAL)
         IVAN (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM (JUDY NEUTRAL)
         GRACE (PREFERRED)
    ---- SAWING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         ALICE (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         HEIDI (NEUTRAL)
TUESDAY (JUDY OFF)
    ---- SAWING 9:00 AM - 4:00 PM (JUDY PREFERRED)
         DAVID (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM (JUDY PREFERRED)
         EVE (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM (JUDY REFUSED)
         FRANK (NEUTRAL)
    ---- SAWING 2:00 PM - 9:00 PM (JUDY REFUSED)
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM (JUDY REFUSED)
         HEIDI (NEUTRAL)
WEDNESDAY (JUDY SCHEDULED)
    ---- SAWING 7:30 AM - 2:30 PM (JUDY REFUSED)
         DAVID (PREFERRED)
    ---- PAINTING 7:30 AM - 2:30 PM (JUDY REFUSED)
         IVAN (PREFERRED)
    ---- SANDING 9:45 AM - 4:45 PM (JUDY NEUTRAL)
         FRANK (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM (JUDY PREFERRED)
         JUDY (PREFERRED)
    ---- SAWING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         ALICE (NEUTRAL)
THURSDAY (JUDY SCHEDULED)
    ---- SANDING 9:00 AM - 4:00 PM (JUDY PREFERRED)
         GRACE (PREFERRED)
    ---- SAWING 9:00 AM - 4:00 PM (JUDY PREFERRED)
         CAROL (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM (JUDY PREFERRED)
         EVE (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM (JUDY PREFERRED)
         JUDY (PREFERRED)
    ---- SAWING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         ALICE (NEUTRAL)
FRIDAY (JUDY OFF)
    ---- SAWING 9:00 AM - 4:00 PM (JUDY DISFAVORED)
         DAVID (PREFERRED)
    ---- PAINTING 9:45 AM - 4:45 PM (JUDY DISFAVORED)
         FRANK (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM (JUDY DISFAVORED)
         GRACE (NEUTRAL)
    ---- SAWING 2:00 PM - 9:00 PM (JUDY REFUSED)
         BOB (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM (JUDY REFUSED)
         HEIDI (NEUTRAL)
SATURDAY (JUDY OFF)
    ---- SAWING 7:30 AM - 2:30 PM (JUDY REFUSED)
         CAROL (PREFERRED)
    ---- PAINTING 7:30 AM - 2:30 PM (JUDY REFUSED)
         IVAN (PREFERRED)
    ---- SANDING 9:45 AM - 4:45 PM (JUDY REFUSED)
         DAVID (PREFERRED)
    ---- PAINTING 12:00 PM - 7:00 PM (JUDY DISFAVORED)
         FRANK (NEUTRAL)
    ---- SAWING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         ALICE (PREFERRED)
    ---- PAINTING 2:00 PM - 9:00 PM (JUDY DISFAVORED)
         BOB (NEUTRAL)
SUMMARY
-- ALICE
   benefit: 13.000
   3 PREFERRED
   2 NEUTRAL
   0 DISFAVORED
-- BOB
   benefit: 14.000
   4 PREFERRED
   1 NEUTRAL
   0 DISFAVORED
-- CAROL
   benefit: 9.000
   3 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- DAVID
   benefit: 15.000
   5 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- EVE
   benefit: 9.000
   3 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- FRANK
   benefit: 13.000
   3 PREFERRED
   2 NEUTRAL
   0 DISFAVORED
-- GRACE
   benefit: 8.000
   2 PREFERRED
   1 NEUTRAL
   0 DISFAVORED
-- HEIDI
   benefit: 9.000
   1 PREFERRED
   3 NEUTRAL
   0 DISFAVORED
-- IVAN
   benefit: 12.000
   4 PREFERRED
   0 NEUTRAL
   0 DISFAVORED
-- JUDY
   benefit: 6.000
   2 PREFERRED
   0 NEUTRAL
   0 DISFAVORED

benefit_boost_Nshifts = \
     2: -0.8,
     3: -0.5,
     4: -0.3,
     5: -0.2 
for h in humans:
    benefits[h] = \
        ... + \
        pulp.lpSum([vars_Nshifts[h][n] * benefit_boost_Nshifts[n] \
                    for n in benefit_boost_Nshifts.keys()])

#!/usr/bin/python3
import numpy as np
import gnuplotlib as gp
Nshifts_eq  = 4
Nshifts_max = 10
Nshifts = np.arange(Nshifts_max+1)
i0 = np.nonzero(Nshifts != Nshifts_eq)[0]
i1 = np.nonzero(Nshifts == Nshifts_eq)[0]
gp.plot( # True value: var_Nshifts4==0, Nshifts!=4
         ( np.zeros(i0.shape),
           Nshifts[i0],
           dict(_with     = 'points pt 7 ps 1 lc "red"') ),
         # True value: var_Nshifts4==1, Nshifts==4
         ( np.ones(i1.shape),
           Nshifts[i1],
           dict(_with     = 'points pt 7 ps 1 lc "red"') ),
         # False value: var_Nshifts4==1, Nshifts!=4
         ( np.ones(i0.shape),
           Nshifts[i0],
           dict(_with     = 'points pt 7 ps 1 lc "black"') ),
         # False value: var_Nshifts4==0, Nshifts==4
         ( np.zeros(i1.shape),
           Nshifts[i1],
           dict(_with     = 'points pt 7 ps 1 lc "black"') ),
        unset=('grid'),
        _set = (f'xtics ("(Nshifts== Nshifts_eq ) == 0" 0, "(Nshifts== Nshifts_eq ) == 1" 1)'),
        _xrange = (-0.1, 1.1),
        ylabel = "Nshifts",
        title = "Nshifts equality variable: not linearly separable",
        hardcopy = "/tmp/scheduling-Nshifts-eq.svg")

#!/usr/bin/python3
import numpy as np
import numpysane as nps
import gnuplotlib as gp
Nshifts_leq = 4
Nshifts_max = 10
Nshifts = np.arange(Nshifts_max+1)
i0 = np.nonzero(Nshifts >  Nshifts_leq)[0]
i1 = np.nonzero(Nshifts <= Nshifts_leq)[0]
def linear_slope_yintercept(xy0,xy1):
    m = (xy1[1] - xy0[1])/(xy1[0] - xy0[0])
    b = xy1[1] - m * xy1[0]
    return np.array(( m, b ))
x01     = np.arange(2)
x01_one = nps.glue( nps.transpose(x01), np.ones((2,1)), axis=-1)
y_lowerbound = nps.inner(x01_one,
                         linear_slope_yintercept( np.array((0, Nshifts_leq+1)),
                                                  np.array((1, 0)) ))
y_upperbound = nps.inner(x01_one,
                         linear_slope_yintercept( np.array((0, Nshifts_max)),
                                                  np.array((1, Nshifts_leq)) ))
y_lowerbound_check = (1-x01) * (Nshifts_leq+1)
y_upperbound_check = Nshifts_max - x01*(Nshifts_max-Nshifts_leq)
gp.plot( # True value: var_Nshifts_leq4==0, Nshifts>4
         ( np.zeros(i0.shape),
           Nshifts[i0],
           dict(_with     = 'points pt 7 ps 1 lc "red"') ),
         # True value: var_Nshifts_leq4==1, Nshifts<=4
         ( np.ones(i1.shape),
           Nshifts[i1],
           dict(_with     = 'points pt 7 ps 1 lc "red"') ),
         # False value: var_Nshifts_leq4==1, Nshifts>4
         ( np.ones(i0.shape),
           Nshifts[i0],
           dict(_with     = 'points pt 7 ps 1 lc "black"') ),
         # False value: var_Nshifts_leq4==0, Nshifts<=4
         ( np.zeros(i1.shape),
           Nshifts[i1],
           dict(_with     = 'points pt 7 ps 1 lc "black"') ),
         ( x01, y_lowerbound, y_upperbound,
           dict( _with     = 'filledcurves lc "green"',
                 tuplesize = 3) ),
         ( x01, nps.cat(y_lowerbound_check, y_upperbound_check),
           dict( _with     = 'lines lc "green" lw 2',
                 tuplesize = 2) ),
        unset=('grid'),
        _set = (f'xtics ("(Nshifts<= Nshifts_leq ) == 0" 0, "(Nshifts<= Nshifts_leq ) == 1" 1)',
                'style fill transparent pattern 1'),
        _xrange = (-0.1, 1.1),
        ylabel = "Nshifts",
        title = "Nshifts inequality variable: linearly separable",
        hardcopy = "/tmp/scheduling-Nshifts-leq.svg")

# I want to favor people getting more extra shifts at the start to balance
# things out: somebody getting one more shift on their pile shouldn't take
# shifts away from under-utilized people
benefit_boost_leq_bound = \
     2: .2,
     3: .3,
     4: .4,
     5: .5 
# Constrain vars_Nshifts_leq variables to do the right thing
for h in humans:
    for b in benefit_boost_leq_bound.keys():
        prob += (pulp.lpSum([vars[h][s] for s in shifts.keys()])
                 >= (1 - vars_Nshifts_leq[h][b])*(b+1),
                 f" h  at least  b  shifts: lower bound")
        prob += (pulp.lpSum([vars[h][s] for s in shifts.keys()])
                 <= Nshifts_max - vars_Nshifts_leq[h][b]*(Nshifts_max-b),
                 f" h  at least  b  shifts: upper bound")
benefits = dict()
for h in humans:
    benefits[h] = \
        ... + \
        pulp.lpSum([vars_Nshifts_leq[h][b] * benefit_boost_leq_bound[b] \
                    for b in benefit_boost_leq_bound.keys()])

Comparison of architecture and mainstream adoption potential

Protocol	Identity System	Example	Storage model	Cost for end users	Potential
Mastodon	Tied to server domain	@ottok@mastodon.social	Federated instances	Free (some instances charge)	High
Bluesky	Portable (DID)	ottoke.bsky.social	Federated instances	Free	Moderate
Farcaster	ENS (Ethereum)	@ottok	Blockchain + off-chain	Small gas fees	Moderate
Lens	NFT-based (Polygon)	@ottok	Blockchain + off-chain	Small gas fees	Niche
Nostr	Cryptographic Keys	npub16lc6uhqpg6dnqajylkhwuh3j7ynhcnje508tt4v6703w9kjlv9vqzz4z7f	Federated instances	Free (some instances charge)	Niche

1. Mastodon (ActivityPub) Mastodon was created in 2016 by Eugen Rochko, a German software developer who sought to provide a decentralized and user-controlled alternative to Twitter. It was built on the ActivityPub protocol, now standardized by W3C Social Web Working Group, to allow users to join independent servers while still communicating across the broader Mastodon network. Mastodon operates on a federated model, where multiple independently run servers communicate via ActivityPub. Each server sets its own moderation policies, leading to a decentralized but fragmented experience. The servers can alternatively be called instances, relays or nodes, depending on what vocabulary a protocol has standardized on.

• Identity: User identity is tied to the instance where they registered, represented as @username@instance.tld.
• Storage: Data is stored on individual instances, which federate messages to other instances based on their configurations.
• Cost: Free to use, but relies on instance operators willing to run the servers.

The protocol defines multiple activities such as:

• Creating a post
• Liking
• Sharing
• Following
• Commenting

Example Message in ActivityPub (JSON-LD Format)

json Copy

"@context": "https://www.w3.org/ns/activitystreams", "type": "Create", "actor": "https://mastodon.social/users/ottok", "object": "type": "Note", "content": "Hello from #Mastodon!", "published": "2025-03-03T12:00:00Z", "to": ["https://www.w3.org/ns/activitystreams#Public"]

 
 "@context": "https://www.w3.org/ns/activitystreams",
 "type": "Create",
 "actor": "https://mastodon.social/users/ottok",
 "object":  
 "type": "Note",
 "content": "Hello from #Mastodon!",
 "published": "2025-03-03T12:00:00Z",
 "to": ["https://www.w3.org/ns/activitystreams#Public"]
  
 

Servers communicate across different platforms by publishing activities to their followers or forwarding activities between servers. Standard HTTPS is used between servers for communication, and the messages use JSON-LD for data representation. The WebFinger protocol is used for user discovery. There is however no neat way for home server discovery yet. This means that if you are browsing e.g. Fosstodon and want to follow a user and press Follow, a dialog will pop up asking you to enter your own home server (e.g. mastodon.social) to redirect you there for actually executing the Follow action on with your account. Mastodon is open source under the AGPL at github.com/mastodon/mastodon. Anyone can operate their own instance. It just requires to run your own server and some skills to maintain a Ruby on Rails app with a PostgreSQL database backend, and basic understanding of the protocol to configure federation with other ActivityPub instances.

Popularity: Already established, but will it grow more? Mastodon has seen steady growth, especially after Twitter s acquisition in 2022, with some estimates stating it peaked at 10 million users across thousands of instances. However, its fragmented user experience and the complexity of choosing instances have hindered mainstream adoption. Still, it remains the most established decentralized alternative to Twitter. Note that Donald Trump s Truth Social is based on the Mastodon software but does not federate with the ActivityPub network. The ActivityPub protocol is the most widely used of its kind. One of the other most popular services is the Lemmy link sharing service, similar to Reddit. The larger ecosystem of ActivityPub is called Fediverse, and estimates put the total active user count around 6 million.

2. Bluesky (AT Protocol) Interestingly, Bluesky was conceived within Twitter in 2019 by Twitter founder Jack Dorsey. After being incubated as a Twitter-funded project, it spun off as an independent Public Benefit LLC in February 2022 and launched its public beta in February 2023. Bluesky runs on top of the Authenticated Transfer (AT) Protocol published at https://github.com/bluesky-social/atproto. The protocol enables portable identities and data ownership, meaning users can migrate between platforms while keeping their identity and content intact. In practice, however, there is only one popular server at the moment, which is Bluesky itself.

• Identity: Usernames are domain-based (e.g., @user.bsky.social).
• Storage: Content is theoretically federated among various servers.
• Cost: Free to use, but relies on instance operators willing to run the servers.

Example Message in AT Protocol (JSON Format)

json Copy

"repo": "did:plc:ottoke.bsky.social", "collection": "app.bsky.feed.post", "record": "$type": "app.bsky.feed.post", "text": "Hello from Bluesky!", "createdAt": "2025-03-03T12:00:00Z", "langs": ["en"]

 
 "repo": "did:plc:ottoke.bsky.social",
 "collection": "app.bsky.feed.post",
 "record":  
 "$type": "app.bsky.feed.post",
 "text": "Hello from Bluesky!",
 "createdAt": "2025-03-03T12:00:00Z",
 "langs": ["en"]
  
 

Popularity: Hybrid approach may have business benefits? Bluesky reported over 3 million users by 2024, probably getting traction due to its Twitter-like interface and Jack Dorsey s involvement. Its hybrid approach decentralized identity with centralized components could make it a strong candidate for mainstream adoption, assuming it can scale effectively.

3. Warpcast (Farcaster Network) Farcaster was launched in 2021 by Dan Romero and Varun Srinivasan, both former crypto exchange Coinbase executives, to create a decentralized but user-friendly social network. Built on the Ethereum blockchain, it could potentially offer a very attack-resistant communication medium. However, in my own testing, Farcaster does not seem to fully leverage what Ethereum could offer. First of all, there is no diversity in programs implementing the protocol as at the moment there is only Warpcast. In Warpcast the signup requires an initial 5 USD fee that is not payable in ETH, and users need to create a new wallet address on the Ethereum layer 2 network Base instead of simply reusing their existing Ethereum wallet address or ENS name. Despite this, I can understand why Farcaster may have decided to start out like this. Having a single client program may be the best strategy initially. One of the decentralized chat protocol Matrix founders, Matthew Hodgson, shared in his FOSDEM 2025 talk that he slightly regrets focusing too much on developing the protocol instead of making sure the app to use it is attractive to end users. So it may be sensible to ensure Warpcast gets popular first, before attempting to make the Farcaster protocol widely used. As a protocol Farcaster s hybrid approach makes it more scalable than fully on-chain networks, giving it a higher chance of mainstream adoption if it integrates seamlessly with broader Web3 ecosystems.

• Identity: ENS (Ethereum Name Service) domains are used as usernames.
• Storage: Messages are stored in off-chain hubs, while identity is on-chain.
• Cost: Users must pay gas fees for some operations but reading and posting messages is mostly free.

Example Message in Farcaster (JSON Format)

json Copy

"fid": 766579, "username": "ottok", "custodyAddress": "0x127853e48be3870172baa4215d63b6d815d18f21", "connectedWallet": "0x3ebe43aa3ae5b891ca1577d9c49563c0cee8da88", "text": "Hello from Farcaster!", "publishedAt": 1709424000, "replyTo": null, "embeds": []

 
 "fid": 766579,
 "username": "ottok",
 "custodyAddress": "0x127853e48be3870172baa4215d63b6d815d18f21",
 "connectedWallet": "0x3ebe43aa3ae5b891ca1577d9c49563c0cee8da88",
 "text": "Hello from Farcaster!",
 "publishedAt": 1709424000,
 "replyTo": null,
 "embeds": []
 

Popularity: Decentralized social media + decentralized payments a winning combo? Ethereum founder Vitalik Buterin (warpcast.com/vbuterin) and many core developers are active on the platform. Warpcast, the main client for Farcaster, has seen increasing adoption, especially among Ethereum developers and Web3 enthusiasts. I too have an profile at warpcast.com/ottok. However, the numbers are still very low and far from reaching network effects to really take off. Blockchain-based social media networks, particularly those built on Ethereum, are compelling because they leverage existing user wallets and persistent identities while enabling native payment functionality. When combined with decentralized content funding through micropayments, these blockchain-backed social networks could offer unique advantages that centralized platforms may find difficult to replicate, being decentralized both as a technical network and in a funding mechanism.

4. Hey.xyz (Lens Network) The Lens Protocol was developed by decentralized finance (DeFi) team Aave and launched in May 2022 to provide a user-owned social media network. While initially built on Polygon, it has since launched its own Layer 2 network called the Lens Network in February 2024. Lens is currently the main competitor to Farcaster. Lens stores profile ownership and references on-chain, while content is stored on IPFS/Arweave, enabling composability with DeFi and NFTs.

• Identity: Profile ownership is tied to NFTs on the Polygon blockchain.
• Storage: Content is on-chain and integrates with IPFS/Arweave (like NFTs).
• Cost: Users must pay gas fees for some operations but reading and posting messages is mostly free.

Example Message in Lens (JSON Format)

json Copy

"profileId": "@ottok", "contentURI": "ar://QmExampleHash", "collectModule": "0x23b9467334bEb345aAa6fd1545538F3d54436e96", "referenceModule": "0x0000000000000000000000000000000000000000", "timestamp": 1709558400

 
 "profileId": "@ottok",
 "contentURI": "ar://QmExampleHash",
 "collectModule": "0x23b9467334bEb345aAa6fd1545538F3d54436e96",
 "referenceModule": "0x0000000000000000000000000000000000000000",
 "timestamp": 1709558400
 

Popularity: Probably not as social media site, but maybe as protocol? The social media side of Lens is mainly the Hey.xyz website, which seems to have fewer users than Warpcast, and is even further away from reaching critical mass for network effects. The Lens protocol however has a lot of advanced features and it may gain adoption as the building block for many Web3 apps.

5. Primal.net (Nostr Network) Nostr (Notes and Other Stuff Transmitted by Relays) was conceptualized in 2020 by an anonymous developer known as fiatjaf. One of the primary design tenets was to be a censorship-resistant protocol and it is popular among Bitcoin enthusiasts, with Jack Dorsey being one of the public supporters. Unlike the Farcaster and Lens protocols, Nostr is not blockchain-based but just a network of relay servers for message distribution. If does however use public key cryptography for identities, similar to how wallets work in crypto.

• Identity: Public-private key pairs define identity (with prefix npub...).
• Storage: Content is federated among multiple servers, which in Nostr vocabulary are called relays.
• Cost: No gas fees, but relies on relay operators willing to run the servers.

Example Message in Nostr (JSON Format)

json Copy

"id": "note1xyz...", "pubkey": "npub1...", "kind": 1, "content": "Hello from Nostr!", "created_at": 1709558400, "tags": [], "sig": "sig1..."

 
 "id": "note1xyz...",
 "pubkey": "npub1...",
 "kind": 1,
 "content": "Hello from Nostr!",
 "created_at": 1709558400,
 "tags": [],
 "sig": "sig1..."
 

Popularity: If Jack Dorsey and Bitcoiners promote it enough? Primal.net as a web app is pretty solid, but it does not stand out much. While Jack Dorsey has shown support by donating $1.5 million to the protocol development in December 2021, its success likely depends on broader adoption by the Bitcoin community.

Will any of these replace X/Twitter? As usage patterns vary, the statistics are not fully comparable, but this overview of the situation in March 2025 gives a decent overview.

Platform	Total Accounts	Active Users	Growth Trend
Mastodon	~10 million	~1 million	Steady
Bluesky	~33 million	~1 million	Steady
Nostr	~41 million	~20 thousand	Steady
Farcaster	~850 thousand	~50 thousand	Flat
Lens	~140 thousand	~20 thousand	Flat

Mastodon and Bluesky have already reached millions of users, while Lens and Farcaster are growing within crypto communities. It is however clear that none of these are anywhere close to how popular X/Twitter is. In particular, Mastodon had a huge influx of users in the fall of 2022 when Twitter was acquired, but to challenge the incumbents the growth would need to significantly accelerate. We can all accelerate this development by embracing decentralized social media now alongside existing dominant platforms. Who knows, given the right circumstances maybe X.com leadership decides to change the operating model and start federating contents to break out from a walled garden model. The likelyhood of such development would increase if decentralized networks get popular, and the encumbents feel they need to participate to not lose out.

Past and future The idea of decentralized social media is not new. One early pioneer identi.ca launched in 2008, only two years after Twitter, using the OStatus protocol to promote decentralization. A few years later it evolved into pump.io with the ActivityPump protocol, and also forked into GNU Social that continued with OStatus. I remember when these happened, and that in 2010 also Diaspora launched with fairly large publicity. Surprisingly both of these still operate (I can still post both on identi.ca and diasp.org), but the activity fizzled out years ago. The protocol however survived partially and evolved into ActivityPub, which is now the backbone of the Fediverse. The evolution of decentralized social media over the next decade will likely parallel developments in democracy, freedom of speech and public discourse. While the early 2010s emphasized maximum independence and freedom, the late 2010s saw growing support for content moderation to combat misinformation. The AI era introduces new challenges, potentially requiring proof-of-humanity verification for content authenticity. Key factors that will determine success:

• User experience and ease of onboarding
• Network effects and critical mass of users
• Integration with existing web3 infrastructure
• Balance between decentralization and usability
• Sustainable economic models for infrastructure

This is clearly an area of development worth monitoring closely, as the next few years may determine which protocol becomes the de facto standard for decentralized social communication.

"My read on the FTP masters is:

• In truth, they are the heart of the project.
• They know it.
• They do a fantastic job."

• Fixed more than one package per day, typically addressing multiple bugs.
• Added and corrected numerous Homepage fields and watch files.
• The most frequently patched issue was "Fails To Cross-Build From Source" (all including patches).
• Migrated several packages from cdbs/debhelper to dh.
• Rewrote many d/copyright files to DEP5 format and thoroughly reviewed them.
• Integrated all affected packages into Salsa and enabled Salsa CI.
• Approximately half of the packages were moved to appropriate teams, while the rest are maintained within the Debian or Salvage teams.
• Regularly performed team uploads, ITS, NMUs, or QA uploads.
• Filed several RoQA bugs to propose package removals where appropriate.
• Reported multiple maintainers to the MIA team when necessary.

1. FOSSASIA Summit 2025 (March 13-15, Bangkok, Thailand) Schedule: https://eventyay.com/e/4c0e0c27/schedule
2. Chemnitzer Linux-Tage (March 22-23, Chemnitz, Germany) Schedule: https://chemnitzer.linux-tage.de/2025/de/programm/vortraege

Cool things Current directory gets shortened, ~/wikis/anarc.at/software/desktop/wayland shows up as ~/w/a/s/d/wayland Autocompletion rocks. Default prompt rocks. Doesn't seem vulnerable to command injection assaults, at least it doesn't trip on the git-landmine. It even includes pipe status output, which was a huge pain to implement in bash. Made me realized that if the last command succeeds, we don't see other failures, which is the case of my current prompt anyways! Signal reporting is better than my bash implementation too. So far the only modification I have made to the prompt is to add a printf '\a' to output a bell. By default, fish keeps a directory history (but separate from the pushd stack), that can be navigated with cdh, prevd, and nextd, dirh shows the history.

Less cool I feel there's visible latency in the prompt creation. POSIX-style functions (foo() true ) are unsupported. Instead, fish uses whitespace-sensitive definitions like this:

function foo
    true
end

This means my (modest) collection of POSIX functions need to be ported to fish. Workaround: simple functions can be turned into aliases, which fish supports (but implements using functions). EOF heredocs are considered to be "minor syntactic sugar". I find them frigging useful. Process substitution is split on newlines, not whitespace. you need to pipe through string split -n " " to get the equivalent. <(cmd) doesn't exist: they claim you can use cmd foo - as a replacement, but that's not correct: I used <(cmd) mostly where foo does not support - as a magic character to say 'read from stdin'. Documentation is... limited. It seems mostly geared the web docs which are... okay (but I couldn't find out about ~/.config/fish/conf.d there!), but this is really inconvenient when you're trying to browse the manual pages. For example, fish thinks there's a fish_prompt manual page, according to its own completion mechanism, but man(1) cannot find that manual page. I can't find the manual for the time command (which is actually a keyword!) Fish renders multi-line commands with newlines. So if your terminal looks like this, say:

anarcat@angela:~> sq keyring merge torproject-keyring/lavamind-
95F341D746CF1FC8B05A0ED5D3F900749268E55E.gpg torproject-keyrin
g/weasel-E3ED482E44A53F5BBE585032D50F9EBC09E69937.gpg   wl-copy

... but it's actually one line, when you copy-paste the above, in foot(1), it will show up exactly like this, newlines and all:

sq keyring merge torproject-keyring/lavamind-
95F341D746CF1FC8B05A0ED5D3F900749268E55E.gpg torproject-keyrin
g/weasel-E3ED482E44A53F5BBE585032D50F9EBC09E69937.gpg   wl-copy

Whereas it should show up like this:

sq keyring merge torproject-keyring/lavamind-95F341D746CF1FC8B05A0ED5D3F900749268E55E.gpg torproject-keyring/weasel-E3ED482E44A53F5BBE585032D50F9EBC09E69937.gpg   wl-copy

Note that this is an issue specific to foot(1), alacritty(1) and gnome-terminal(1) don't suffer from that issue. I have already filed it upstream in foot and it is apparently fixed already. Globbing is driving me nuts. You can't pass a * to a command unless fish agrees it's going to match something. You need to escape it if it doesn't immediately match, and then you need the called command to actually support globbing. 202[345] doesn't match folders named 2023, 2024, 2025, it will send the string 202[345] to the command.

Blockers () is like $(): it's process substitution, and not a subshell. This is really impractical: I use ( cd foo ; do_something) all the time to avoid losing the current directory... I guess I'm supposed to use pushd for this, but ouch. This wouldn't be so bad if it was just for cd though. Clean constructs like this:

( git grep -l '^#!/.*bin/python' ; fdfind .py )   sort -u

Turn into what i find rather horrible:

begin; git grep -l '^#!/.*bin/python' ; fdfind .py ; end   sort -ub

It... works, but it goes back to "oh dear, now there's a new langage again". I only found out about this construct while trying:

  git grep -l '^#!/.*bin/python' ; fdfind .py     sort -u 

... which fails and suggests using begin/end, at which point: why not just support the curly braces? FOO=bar is not allowed. It's actually recognized syntax, but creates a warning. We're supposed to use set foo bar instead. This really feels like a needless divergence from standard. Aliases are... peculiar. Typical constructs like alias mv="\mv -i" don't work because fish treats aliases as a function definition, and \ is not magical there. This can be worked around by specifying the full path to the command, with e.g. alias mv="/bin/mv -i". Another problem is trying to override a built-in, which seems completely impossible. In my case, I like the time(1) command the way it is, thank you very much, and fish provides no way to bypass that builtin. It is possible to call time(1) with command time, but it's not possible to replace the command keyword so that means a lot of typing. Again: you can't use \ to bypass aliases. This is a huge annoyance for me. I would need to learn to type command in long form, and I use that stuff pretty regularly. I guess I could alias command to c or something, but this is one of those huge muscle memory challenges. alt . doesn't always work the way i expect.

$ timew summary 2025-02-18 Debian
Wk Date       Day Tags                            Start      End    Time   Total
W8 2025-02-18 Tue CVE-2025-26465, Debian,       9:41:44 10:24:17 0:42:33
                  next, openssh
                  Debian, FTBFS with GCC-15,   10:24:17 10:27:12 0:02:55
                  icoutils
                  Debian, FTBFS with GCC-15,   11:50:05 11:57:25 0:07:20
                  kali
                  Debian, Upgrade to 0.67,     11:58:21 12:12:41 0:14:20
                  python_holidays
                  Debian, FTBFS with GCC-15,   12:14:15 12:33:19 0:19:04
                  vigor
                  Debian, FTBFS with GCC-15,   12:39:02 12:39:38 0:00:36
                  python_setproctitle
                  Debian, Upgrade to 1.3.4,    12:39:39 12:46:05 0:06:26
                  python_setproctitle
                  Debian, FTBFS with GCC-15,   12:48:28 12:49:42 0:01:14
                  python_setproctitle
                  Debian, Upgrade to 3.4.1,    12:52:07 13:02:27 0:10:20 1:44:48
                  python_charset_normalizer
                                                                         1:44:48

#! /usr/bin/python3
"""
Summarize timewarrior data, grouped and sorted by time spent.
"""
import json
import subprocess
from argparse import ArgumentParser, RawDescriptionHelpFormatter
from collections import defaultdict
from datetime import datetime, timedelta, timezone
from operator import itemgetter
from rich import box, print
from rich.table import Table
parser = ArgumentParser(
    description=__doc__, formatter_class=RawDescriptionHelpFormatter
)
parser.add_argument("-t", "--only-total", default=False, action="store_true")
parser.add_argument(
    "range",
    nargs="?",
    default=":today",
    help="Time range (usually a hint, e.g. :lastweek)",
)
parser.add_argument("tag", nargs="*", help="Tags to filter by")
args = parser.parse_args()
entries: defaultdict[str, timedelta] = defaultdict(timedelta)
now = datetime.now(timezone.utc)
for entry in json.loads(
    subprocess.run(
        ["timew", "export", args.range, *args.tag],
        check=True,
        capture_output=True,
        text=True,
    ).stdout
):
    start = datetime.fromisoformat(entry["start"])
    if "end" in entry:
        end = datetime.fromisoformat(entry["end"])
    else:
        end = now
    entries[", ".join(entry["tags"])] += end - start
if not args.only_total:
    table = Table(box=box.SIMPLE, highlight=True)
    table.add_column("Tags")
    table.add_column("Time", justify="right")
    for tags, time in sorted(entries.items(), key=itemgetter(1), reverse=True):
        table.add_row(tags, str(time))
    print(table)
total = sum(entries.values(), start=timedelta())
hours, rest = divmod(total, timedelta(hours=1))
minutes, rest = divmod(rest, timedelta(minutes=1))
seconds = rest.seconds
print(f"Total time:  hours:02 : minutes:02 : seconds:02 ")

$ summarize-time 2025-02-18 Debian
  Tags                                                     Time
  
  CVE-2025-26465, Debian, next, openssh                 0:42:33
  Debian, FTBFS with GCC-15, vigor                      0:19:04
  Debian, Upgrade to 0.67, python_holidays              0:14:20
  Debian, Upgrade to 3.4.1, python_charset_normalizer   0:10:20
  Debian, FTBFS with GCC-15, kali                       0:07:20
  Debian, Upgrade to 1.3.4, python_setproctitle         0:06:26
  Debian, FTBFS with GCC-15, icoutils                   0:02:55
  Debian, FTBFS with GCC-15, python_setproctitle        0:01:50
Total time: 01:44:48

$ qalc '62:46:30 - 51:02:42 to time'
(225990 / 3600)   (183762 / 3600) = 11:43:48

$ summarize-time -t :month Freexian
Total time: 69:19:42
$ summarize-time -t :month Debian
Total time: 24:05:30
$ qalc '24:05:30 / (24:05:30 + 69:19:42) to %'
(86730 / 3600) / ((86730 / 3600) + (249582 / 3600))   25.78855349%

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can sponsor me at GitHub.

• https://cdimage.debian.org/cdimage/
• The newest netinst ISO
• Newest Debian live testing with GNOME
• There's no official Debian stable ISO using the backports kernel
• The FAIme web service creates custom images using Debian stable with a newer kernel
• The oldest image: Other-Maybe-Official - Debian-i386 2.1 Disc 1.iso

• Download Debian
• Installing Debian via the Internet
• Debian installation media for USB, CD, DVD
• Network install from a minimal USB,CD
• Live install images
• Downloading Debian USB/CD/DVD images via HTTP/FTP
• Downloading Debian USB/CD/DVD images with BitTorrent
• Downloading Debian USB/CD/DVD images with jigdo
• Installing with the Debian-Installer

• Installer images can be booted on a computer without any OS and then the Debian installer can be started to perform a Debian installation
• Live images boot a Debian desktop without installing anything to the local disks. You can give Debian a try and if you like it you can use the Calamers graphical installer for installing the same desktop onto the local disk.
• Cloud images are meant for running a virtual machine with Debian using QEMU, KVM, OpenStack or in the Amazon AWS cloud or Microsoft Azure cloud.

12.9.0
12.9.0-live
current
current-live

current -> 12.9.0/
current-live -> 12.9.0-live/

amd64
arm64
armel
armhf
i386
mips64el
mipsel
ppc64el
s390x
source
trace

bt-bd
bt-cd
bt-dvd
iso-bd
iso-cd
iso-dvd
jigdo-16G
jigdo-bd
jigdo-cd
jigdo-dlbd
jigdo-dvd
list-16G
list-bd
list-cd
list-dlbd
list-dvd

• bt = BitTorrent, a peer-to-peer file sharing protocol
• iso = directories containing ISO files
• jigdo = a very special download option only for experts who know they really want this
• list = contains lists of the names of the .deb files which are included on the images

• bd = Blu-ray disc (size up to 8GB)
• cd = CD image (size up to 700MB)
• dvd = DVD images (size up to 4.7GB)
• 16G = for an USB stick of 16GB or larger
• dlbd = dual layer Blu-ray disc

  iso-cd/debian-12.9.0-amd64-netinst.iso
  iso-cd/debian-edu-12.9.0-amd64-netinst.iso
  iso-cd/debian-mac-12.9.0-amd64-netinst.iso

debian-live-12.9.0-amd64-xfce.iso
debian-live-12.9.0-amd64-mate.iso
debian-live-12.9.0-amd64-lxqt.iso
debian-live-12.9.0-amd64-gnome.iso
debian-live-12.9.0-amd64-lxde.iso
debian-live-12.9.0-amd64-standard.iso
debian-live-12.9.0-amd64-cinnamon.iso
debian-live-12.9.0-amd64-kde.iso

daily-builds
weekly-builds
weekly-live-builds
trixie_di_alpha1

weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-kde.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-lxde.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-debian-junior.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-standard.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-lxqt.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-mate.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-xfce.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-gnome.iso
weekly-live-builds/amd64/iso-hybrid/debian-live-testing-amd64-cinnamon.iso
weekly-live-builds/arm64/iso-hybrid/debian-live-testing-arm64-gnome.iso

• Other-Maybe-Official - Debian-i386 2.1 Disc 1.iso

#!/usr/bin/python3
import sys
import datetime
import astral.sun
lat  = 34.
year = 2025
city = astral.LocationInfo(latitude=lat, longitude=0)
date0 = datetime.datetime(year, 1, 1)
print("# date sunrise sunset length_min")
for i in range(365):
    date = date0 + datetime.timedelta(days=i)
    s = astral.sun.sun(city.observer, date=date)
    date_sunrise = s['sunrise']
    date_sunset  = s['sunset']
    date_string    = date.strftime('%Y-%m-%d')
    sunrise_string = date_sunrise.strftime('%H:%M')
    sunset_string  = date_sunset.strftime ('%H:%M')
    print(f" date_string   sunrise_string   sunset_string   (date_sunset-date_sunrise).total_seconds()/60 ")

< sunrise-sunset.vnl                   \
  vnl-filter -p date,l='length_min/60' \
  feedgnuplot                          \
  --set 'format x "%b %d"'             \
  --domain                             \
  --timefmt '%Y-%m-%d'                 \
  --lines                              \
  --ylabel 'Day length (hours)'        \
  --hardcopy day-length.svg

$ < sunrise-sunset.vnl vnl-sort -grk length_min   head -n2   vnl-align
#  date    sunrise sunset     length_min   
2025-06-21 04:49   19:14  864.8543702000001
$ < sunrise-sunset.vnl vnl-sort -gk length_min   head -n2   vnl-align
#  date    sunrise sunset     length_min   
2025-12-21 07:01   16:54  592.8354265166668

$ < sunrise-sunset.vnl                                  \
  vnl-filter -p date,d='diff(length_min)'               \
  vnl-filter --has d                                    \
  feedgnuplot                                           \
  --set 'format x "%b %d"'                              \
  --domain                                              \
  --timefmt '%Y-%m-%d'                                  \
  --lines                                               \
  --ylabel 'Daytime gained from the previous day (min)' \
  --hardcopy gain.svg

$ < sunrise-sunset.vnl vnl-filter -p date,d='diff(length_min)'   vnl-filter --has d   vnl-sort -grk d   head -n2   vnl-align
#  date       d   
2025-03-19 2.13167
$ < sunrise-sunset.vnl vnl-filter -p date,d='diff(length_min)'   vnl-filter --has d   vnl-sort -gk d   head -n2   vnl-align
#  date        d   
2025-09-25 -2.09886

> RcppUUID::uuid_generate_time(5)
[1] "0194d8fa-7add-735c-805b-6bbf22b78b9e" "0194d8fa-7add-735e-8012-3e0e53895b19"
[3] "0194d8fa-7add-735e-81af-bc67bb435ade" "0194d8fa-7add-735e-82b1-405bf57963ad"
[5] "0194d8fa-7add-735f-801e-efe57078b2e7"
>

Changes in version 1.2.0 (2025-02-12)

• Time-based UUIDs, ie version 7, can now be generated (requiring Boost 1.86 or newer as in the current BH package)

Changes in version 1.1.2 (2025-01-31)

• New maintainer to resurrect package on CRAN

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can sponsor me at GitHub.

• Rust s two main macro systems
  • macro_rules!
  • proc macros
• derive-deftly to the rescue
  • Example
  • Special-purpose derive macros are now worthwhile!
• Stability without stagnation

define_derive_deftly!  
    export UpdateWorkerReport:
    impl $ttype  
        pub fn update_worker_report(&self, wr: &mut WorkerReport)  
            $(
                $ when fmeta(worker_report) 
                wr.$fname = Some(self.$fname.clone()).into();
            )
         
     
 

#[derive(Debug, Deftly, Clone)]
...
#[derive_deftly(UiMap, UpdateWorkerReport)]
pub struct JobRow  
    ...
    #[deftly(worker_report)]
    pub status: JobStatus,
    pub processing: NoneIsEmpty<ProcessingInfo>,
    #[deftly(worker_report)]
    pub info: String,
    pub duplicate_of: Option<JobId>,
 

    pub fn update_worker_report(&self, wr: &mut WorkerReport)  
        wr.status = Some(self.status.clone()).into();
        wr.info = Some(self.status.clone()).into();
     

Debian Contributions: 2025-01 Contributing to Debian is part of Freexian s mission. This article covers the latest achievements of Freexian and their collaborators. All of this is made possible by organizations subscribing to our Long Term Support contracts and consulting services.

Python 3.13 is now the default Python 3 version in Debian, by Stefano Rivera and Colin Watson The Python 3.13 as default transition has now completed. The next step is to remove Python 3.12 from the archive, which should be very straightforward, it just requires rebuilding C extension packages in no particular order. Stefano fixed some miscellaneous bugs blocking the completion of the 3.13 as default transition.

Fixing qtpaths6 for cross compilation, by Helmut Grohne While Qt5 used to use qmake to query installation properties, Qt6 is moving more and more to CMake and to ease that transition it relies on more qtpaths. Since this tool is not naturally aware of the architecture it is called for, it tends to produce results for the build architecture. Therefore, more than 100 packages were picking up a multiarch directory for the build architecture during cross builds. In collaboration with the Qt/KDE team and Sandro Knau in particular (none affiliated with Freexian), we added an architecture-specific wrapper script in the same way qmake has one for Qt5 and Qt6 already. The relevant CMake module has been updated to prefer the triplet-prefixed wrapper. As a result, most of the KDE packages now cross build on unstable ready in time for the trixie release.

/usr-move, by Helmut Grohne In December, Emil S dergren reported that a live-build was not working for him and in January, Colin Watson reported that the proposed mitigation for debian-installer-utils would practically fail. Both failures were to be attributed to a wrong understanding of implementation-defined behavior in dpkg-divert. As a result, all M18 mitigations had to be reviewed and many of them replaced. Many have been uploaded already and all instances have received updated patches. Even though dumat has been in operation for more than a year, it gained recent changes. For one thing, analysis of architectures other than amd64 was requested. Chris Hofstaedler (not affiliated with Freexian) kindly provided computing resources for repeatedly running it on the larger set. Doing so revealed various cross-architecture undeclared file conflicts in gcc, glibc, and binutils-z80, but it also revealed a previously unknown /usr-move issue in rpi.rpi-common. On top of that, dumat produced false positive diagnostics and wrongly associated Debian bugs in some cases, both of which have now been fixed. As a result, a supposedly fixed python3-sepolicy issue had to be reopened.

rebootstrap, by Helmut Grohne As much as we think of our base system as stable, it is changing a lot and the architecture cross bootstrap tooling is very sensitive to such changes requiring permanent maintenance. A problem that recently surfaced was that building a binutils cross toolchain would result in a binutils-for-host package that would not be practically installable as it would depend on a binutils-common package that was not built. This turned into an examination of binutils-common and noticing that it actually differed across architectures even though it should not. Johannes Schauer Marin Rodrigues (not affiliated with Freexian) and Colin Watson kindly helped brainstorm possible solutions. Eventually, Helmut provided a patch to move gprofng bits out of binutils-common. Independently, Matthias Klose (not affiliated with Freexian) split out binutils-gold into a separate source package. As a result, binutils-common is now equal across architectures and can be marked Multi-Arch: foreign resolving the initial problem.

Salsa CI, by Santiago Ruano Rinc n Santiago continued the work about the sbuild support for Salsa CI, that was mentioned in the previous month report. The !568 merge request that created the new build image was merged, making it easier to test !569 with external projects. Santiago used a fork of the debusine repo to try the draft !569, and some issues were spotted, and part of them fixed. This is the last debusine pipeline run with the current !569: https://salsa.debian.org/santiago/debusine/-/pipelines/794233. One of the last improvements relates to how to enable projects to customize the pipeline, in an equivalent way than they currently do in the extract-source and build jobs. While this is work-in-progress, the results are rather promising. Next steps include deciding on introducing schroot support for bookworm, bookworm-security, and older releases, as they are done in the official debian buildd.

DebConf preparations, by Stefano Rivera and Santiago Ruano Rinc n DebConf will be happening in Brest, France, in July. Santiago continued the DebConf 25 organization work, looking for catering providers. Both Stefano and Santiago have been reaching out to some potential sponsors. DebConf depends on sponsors to cover the organization cost, if your company depends on Debian, please consider sponsoring DebConf. Stefano has been winding up some of the finances from previous DebConfs. Finalizing reimbursements to team members from DebConf 23, and handling some outstanding issues from DebConf 24. Stefano and the rest of the DebConf committee have been reviewing bids for DebConf 26, to select the next venue.

Ruby 3.3 is now the default Ruby interpreter, by Lucas Kanashiro Ruby 3.3 is about to become the default Ruby interpreter for Trixie. Many bugs were fixed by Lucas and the Debian Ruby team during the sprint hold in Paris during Jan 27-31. The next step is to remove support of Ruby 3.1, which is the alternative Ruby interpreter for now. Thanks to the Debian Release team for all the support, especially Emilio Pozuelo Monfort.

Rails 7 transition, by Lucas Kanashiro Rails 6 has been shipped by Debian since Bullseye, and as a WEB framework, many issues (especially security related issues) have been encountered and the maintainability of it becomes harder and harder. With that in mind, during the Debian Ruby team sprint last month, the transition to Rack 3 (an important dependency of rails containing many breaking changes) was started in Debian unstable, it is ongoing. Once it is done, the Rails 7 transition will take place, and Rails 7 should be shipped in Debian Trixie.

Miscellaneous contributions

• Stefano improved a poor ImportError for users of the turtle module on Python 3, who haven t installed the python3-tk package.
• Stefano updated several packages to new upstream releases.
• Stefano added the Python extension to the re2 package, allowing for the use of the Google RE2 regular expression library as a direct replacement for the standard library re module.
• Stefano started provisioning a new physical server for the debian.social infrastructure.
• Carles improved simplemonitor (documentation on systemd integration, worked with upstream for fixing a bug).
• Carles upgraded packages to new upstream versions: python-ring-doorbell and python-asyncclick.
• Carles did po-debconf translations to Catalan: reviewed 44 packages and submitted translations to 90 packages (via salsa merge requests or bugtracker bugs).
• Carles maintained po-debconf-manager with small fixes.
• Rapha l worked on some outstanding DEP-14 merge request and participated in the associated discussion. The discussions have been more contentious than anticipated, somewhat exacerbated by Otto s desire to conclude fast while the required tool support is not yet there.
• Rapha l, with the help of Philipp Kern from the DSA team, upgraded tracker.debian.org to use Django 4.2 (from bookworm-backports) which in turn enabled him to configure authentication via salsa.debian.org. It s now possible to login to tracker.debian.org with your salsa credentials!
• Rapha l updated zim a nice desktop wiki that is very handy to organize your day-to-day digital life to the latest upstream version (0.76).
• Helmut sent patches for 10 cross build failures.
• Helmut continued working on a tool for memory-based concurrency limit of builds.
• Helmut NMUed libtool, opensysusers and virtualbox.
• Enrico tried to support Helmut in working out tricky usrmerge situations
• Thorsten Alteholz uploaded a new upstream version of brlaser.
• Colin Watson upgraded 33 Python packages to new upstream versions, including fixes for CVE-2024-42353, CVE-2024-47532, and CVE-2025-22153.
• Emilio Pozuelo managed various transitions, and fixed various RC bugs (telepathy-glib, xorg, xserver-xorg-video-vesa, apitrace, mesa).
• Anupa attended the monthly team meeting for Debian publicity team and shared the social media stats.
• Anupa assisted Jean-Pierre Giraud in the point release announcement for Debian 12.9 and published the Micronews.
• Anupa took part in multiple Debian publicity team discussions regarding our presence in social media platforms.

I hope to write more next year. I've been thinking about a few posts I could write for work, about how things work behind the scenes at Tor, that could be informative for many people. We run a rather old setup, but things hold up pretty well for what we throw at it, and it's worth sharing that with the world...

A bad year for this blog 2024 was the second worst year ever in my blogging history, tied with 2009 at a measly 6 posts for the year:

anarcat@angela:anarc.at$ curl -sSL https://anarc.at/blog/   grep 'href="\./'   grep -o 20[0-9][0-9]   sort   uniq -c   sort -nr   grep -v 2025   tail -3
      6 2024
      6 2009
      3 2014

I did write about my work though, detailing the migration from Gitolite to GitLab we completed that year. But after August, total radio silence until now.

Loads of drafts It's not that I have nothing to say: I have no less than five drafts in my working tree here, not counting three actual drafts recorded in the Git repository here:

anarcat@angela:anarc.at$ git s blog
## main...origin/main
?? blog/bell-bot.md
?? blog/fish.md
?? blog/kensington.md
?? blog/nixos.md
?? blog/tmux.md
anarcat@angela:anarc.at$ git grep -l '\!tag draft'
blog/mobile-massive-gallery.md
blog/on-dying.mdwn
blog/secrets-recovery.md

I just don't have time to wrap those things up. I think part of me is disgusted by seeing my work stolen by large corporations to build proprietary large language models while my idols have been pushed to suicide for trying to share science with the world. Another part of me wants to make those things just right. The "tagged drafts" above are nothing more than a huge pile of chaotic links, far from being useful for anyone else than me, and even then. The on-dying article, in particular, is becoming my nemesis. I've been wanting to write that article for over 6 years now, I think. It's just too hard.

Writing elsewhere There's also the fact that I write for work already. A lot. Here are the top-10 contributors to our team's wiki:

anarcat@angela:help.torproject.org$ git shortlog --numbered --summary --group="format:%al"   head -10
  4272  anarcat
   423  jerome
   117  zen
   116  lelutin
   104  peter
    58  kez
    45  irl
    43  hiro
    18  gaba
    17  groente

... but that's a bit unfair, since I've been there half a decade. Here's the last year:

anarcat@angela:help.torproject.org$ git shortlog --since=2024-01-01 --numbered --summary --group="format:%al"   head -10
   827  anarcat
   117  zen
   116  lelutin
    91  jerome
    17  groente
    10  gaba
     8  micah
     7  kez
     5  jnewsome
     4  stephen.swift

So I still write the most commits! But to truly get a sense of the amount I wrote in there, we should count actual changes. Here it is by number of lines (from commandlinefu.com):

anarcat@angela:help.torproject.org$ git ls-files   xargs -n1 git blame --line-porcelain   sed -n 's/^author //p'   sort -f   uniq -ic   sort -nr   head -10
  99046 Antoine Beaupr 
   6900 Zen Fu
   4784 J r me Charaoui
   1446 Gabriel Filion
   1146 Jerome Charaoui
    837 groente
    705 kez
    569 Gaba
    381 Matt Traudt
    237 Stephen Swift

That, of course, is the entire history of the git repo, again. We should take only the last year into account, and probably ignore the tails directory, as sneaky Zen Fu imported the entire docs from another wiki there...

anarcat@angela:help.torproject.org$ find [d-s]* -type f -mtime -365   xargs -n1 git blame --line-porcelain 2>/dev/null   sed -n 's/^author //p'   sort -f   uniq -ic   sort -nr   head -10
  75037 Antoine Beaupr 
   2932 J r me Charaoui
   1442 Gabriel Filion
   1400 Zen Fu
    929 Jerome Charaoui
    837 groente
    702 kez
    569 Gaba
    381 Matt Traudt
    237 Stephen Swift

Pretty good! 75k lines. But those are the files that were modified in the last year. If we go a little more nuts, we find that:

anarcat@angela:help.torproject.org$ $ git-count-words-range.py    sort -k6 -nr   head -10
parsing commits for words changes from command: git log '--since=1 year ago' '--format=%H %al'
anarcat 126116 - 36932 = 89184
zen 31774 - 5749 = 26025
groente 9732 - 607 = 9125
lelutin 10768 - 2578 = 8190
jerome 6236 - 2586 = 3650
gaba 3164 - 491 = 2673
stephen.swift 2443 - 673 = 1770
kez 1034 - 74 = 960
micah 772 - 250 = 522
weasel 410 - 0 = 410

I wrote 126,116 words in that wiki, only in the last year. I also deleted 37k words, so the final total is more like 89k words, but still: that's about forty (40!) articles of the average size (~2k) I wrote in 2022. (And yes, I did go nuts and write a new log parser, essentially from scratch, to figure out those word diffs. I did get the courage only after asking GPT-4o for an example first, I must admit.) Let's celebrate that again: I wrote 90 thousand words in that wiki in 2024. According to Wikipedia, a "novella" is 17,500 to 40,000 words, which would mean I wrote about a novella and a novel, in the past year. But interestingly, if I look at the repository analytics. I certainly didn't write that much more in the past year. So that alone cannot explain the lull in my production here.

Arguments Another part of me is just tired of the bickering and arguing on the internet. I have at least two articles in there that I suspect is going to get me a lot of push-back (NixOS and Fish). I know how to deal with this: you need to write well, consider the controversy, spell it out, and defuse things before they happen. But that's hard work and, frankly, I don't really care that much about what people think anymore. I'm not writing here to convince people. I have stop evangelizing a long time ago. Now, I'm more into documenting, and teaching. And, while teaching, there's a two-way interaction: when you give out a speech or workshop, people can ask questions, or respond, and you all learn something. When you document, you quickly get told "where is this? I couldn't find it" or "I don't understand this" or "I tried that and it didn't work" or "wait, really? shouldn't we do X instead", and you learn. Here, it's static. It's my little soapbox where I scream in the void. The only thing people can do is scream back.

Collaboration So. Let's see if we can work together here. If you don't like something I say, disagree, or find something wrong or to be improved, instead of screaming on social media or ignoring me, try contributing back. This site here is backed by a git repository and I promise to read everything you send there, whether it is an issue or a merge request. I will, of course, still read comments sent by email or IRC or social media, but please, be kind. You can also, of course, follow the latest changes on the TPA wiki. If you want to catch up with the last year, some of the "novellas" I wrote include:

• TPA-RFC-33: Monitoring: Nagios to Prometheus conversion, see also the extensive Prometheus documentation we wrote
• TPA-RFC-45: email architecture: draft of long-term email services at torproject.org
• TPA-RFC-62: TPA password manager: switch to password-store
• TPA-RFC-63: storage server budget: buy a new backup storage server (5k$ + 100$/mth)
• TPA-RFC-65: PostgreSQL backups: switching from legacy to pgBackRest for database backups
• TPA-RFC-68: Idle canary servers: provision test servers that sit idle to monitor infrastructure and stage deployments
• TPA-RFC-71: Emergency email deployments, phase B: deploy a new sender-rewriting mail forwarder, migrate mailing lists off the legacy server to a new machine, migrate the remaining Schleuder list to the Tails server, upgrade eugeni.
• TPA-RFC-76: Puppet merge request workflow: how to mirror our private Puppet repo to GitLab safely
• TPA-RFC-79: General merge request workflows: how to use merge requests, assignees, reviewers, draft and threads on GitLab projects

(Well, no, you can't actually follow changes on a GitLab wiki. But we have a wiki-replica git repository where you can see the latest commits, and subscribe to the RSS feed.) See you there!

Qalc commandline primer On Debian, Qalculate's CLI interface can be installed with:

apt install qalc

Then you start it with the qalc command, and end up on a prompt:

anarcat@angela:~$ qalc
> 

Then it's a normal calculator:

anarcat@angela:~$ qalc
> 1+1
  1 + 1 = 2
> 1/7
  1 / 7   0.1429
> pi
  pi   3.142
> 

There's a bunch of variables to control display, approximation, and so on:

> set precision 6
> 1/7
  1 / 7   0.142857
> set precision 20
> pi
  pi   3.1415926535897932385

When I need more, I typically browse around the menus. One big issue I have with Qalculate is there are a lot of menus and features. I had to fiddle quite a bit to figure out that set precision command above. I might add more examples here as I find them.

Bandwidth estimates I often use the data units to estimate bandwidths. For example, here's what 1 megabit per second is over a month ("about 300 GiB"):

> 1 megabit/s * 30 day to gibibyte 
  (1 megabit/second)   (30 days)   301.7 GiB

Or, "how long will it take to download X", in this case, 1GiB over a 100 mbps link:

> 1GiB/(100 megabit/s)
  (1 gibibyte) / (100 megabits/second)   1 min + 25.90 s

Password entropy To calculate how much entropy (in bits) a given password structure, you count the number of possibilities in each entry (say, [a-z] is 26 possibilities, "one word in a 8k dictionary" is 8000), extract the base-2 logarithm, multiplied by the number of entries. For example, an alphabetic 14-character password is:

> log2(26*2)*14
  log (26   2)   14   79.81

... 80 bits of entropy. To get the equivalent in a Diceware password with a 8000 word dictionary, you would need:

> log2(8k)*x = 80
  (log (8   000)   x) = 80  
  x   6.170

... about 6 words, which gives you:

> log2(8k)*6
  log (8   1000)   6   77.79

78 bits of entropy.

Exchange rates You can convert between currencies!

> 1 EUR to USD
  1 EUR   1.038 USD

Even fake ones!

> 1 BTC to USD
  1 BTC   96712 USD

This relies on a database pulled form the internet (typically the central european bank rates, see the source). It will prompt you if it's too old:

It has been 256 days since the exchange rates last were updated.
Do you wish to update the exchange rates now? y

As a reader pointed out, you can set the refresh rate for currencies, as some countries will require way more frequent exchange rates. The graphical version has a little graphical indicator that, when you mouse over, tells you where the rate comes from.

Other conversions Here are other neat conversions extracted from my history

> teaspoon to ml
  teaspoon = 5 mL
> tablespoon to ml
  tablespoon = 15 mL
> 1 cup to ml 
  1 cup   236.6 mL
> 6 L/100km to mpg
  (6 liters) / (100 kilometers)   39.20 mpg
> 100 kph to mph
  100 kph   62.14 mph
> (108km - 72km) / 110km/h
  ((108 kilometers)   (72 kilometers)) / (110 kilometers/hour)  
  19 min + 38.18 s

Completion time estimates This is a more involved example I often do.

Background Say you have started a long running copy job and you don't have the luxury of having a pipe you can insert pv(1) into to get a nice progress bar. For example, rsync or cp -R can have that problem (but not tar!). (Yes, you can use --info=progress2 in rsync, but that estimate is incremental and therefore inaccurate unless you disable the incremental mode with --no-inc-recursive, but then you pay a huge up-front wait cost while the entire directory gets crawled.)

Extracting a process start time First step is to gather data. Find the process start time. If you were unfortunate enough to forget to run date --iso-8601=seconds before starting, you can get a similar timestamp with stat(1) on the process tree in /proc with:

$ stat /proc/11232
  File: /proc/11232
  Size: 0               Blocks: 0          IO Block: 1024   directory
Device: 0,21    Inode: 57021       Links: 9
Access: (0555/dr-xr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2025-02-07 15:50:25.287220819 -0500
Modify: 2025-02-07 15:50:25.287220819 -0500
Change: 2025-02-07 15:50:25.287220819 -0500
 Birth: -

So our start time is 2025-02-07 15:50:25, we shave off the nanoseconds there, they're below our precision noise floor. If you're not dealing with an actual UNIX process, you need to figure out a start time: this can be a SQL query, a network request, whatever, exercise for the reader.

Saving a variable This is optional, but for the sake of demonstration, let's save this as a variable:

> start="2025-02-07 15:50:25"
  save("2025-02-07T15:50:25"; start; Temporary; ; 1) =
  "2025-02-07T15:50:25"

Estimating data size Next, estimate your data size. That will vary wildly with the job you're running: this can be anything: number of files, documents being processed, rows to be destroyed in a database, whatever. In this case, rsync tells me how many bytes it has transferred so far:

# rsync -ASHaXx --info=progress2 /srv/ /srv-zfs/
2.968.252.503.968  94%    7,63MB/s    6:04:58  xfr#464440, ir-chk=1000/982266) 

Strip off the weird dots in there, because that will confuse qalculate, which will count this as:

  2.968252503968 bytes   2.968 B

Or, essentially, three bytes. We actually transferred almost 3TB here:

  2968252503968 bytes   2.968 TB

So let's use that. If you had the misfortune of making rsync silent, but were lucky enough to transfer entire partitions, you can use df (without -h! we want to be more precise here), in my case:

Filesystem              1K-blocks       Used  Available Use% Mounted on
/dev/mapper/vg_hdd-srv 7512681384 7258298036  179205040  98% /srv
tank/srv               7667173248 2870444032 4796729216  38% /srv-zfs

(Otherwise, of course, you use du -sh $DIRECTORY.)

Digression over bytes Those are 1 K bytes which is actually (and rather unfortunately) Ki, or "kibibytes" (1024 bytes), not "kilobytes" (1000 bytes). Ugh.

> 2870444032 KiB
  2870444032 kibibytes   2.939 TB

> 2870444032 kB
  2870444032 kilobytes   2.870 TB

At this scale, those details matter quite a bit, we're talking about a 69GB (64GiB) difference here:

> 2870444032 KiB - 2870444032 kB
  (2870444032 kibibytes)   (2870444032 kilobytes)   68.89 GB

Anyways. Let's take 2968252503968 bytes as our current progress. Our entire dataset is 7258298064 KiB, as seen above.

Solving a cross-multiplication We have 3 out of four variables for our equation here, so we can already solve:

> (now-start)/x = (2996538438607 bytes)/(7258298064 KiB) to h
  ((actual   start) / x) = ((2996538438607 bytes) / (7258298064
  kibibytes))
  x   59.24 h

The entire transfer will take about 60 hours to complete! Note that's not the time left, that is the total time. To break this down step by step, we could calculate how long it has taken so far:

> now-start
  now   start   23 h + 53 min + 6.762 s
> now-start to s
  now   start   85987 s

... and do the cross-multiplication manually, it's basically:

x/(now-start) = (total/current)

so:

x = (total/current) * (now-start)

or, in Qalc:

> ((7258298064  kibibytes) / ( 2996538438607 bytes) ) *  85987 s
  ((7258298064 kibibytes) / (2996538438607 bytes))   (85987 secondes)  
  2 d + 11 h + 14 min + 38.81 s

It's interesting it gives us different units here! Not sure why.

Now and built-in variables The now here is actually a built-in variable:

> now
  now   "2025-02-08T22:25:25"

There is a bewildering list of such variables, for example:

> uptime
  uptime = 5 d + 6 h + 34 min + 12.11 s
> golden
  golden   1.618
> exact
  golden = ( (5) + 1) / 2

Computing dates In any case, yay! We know the transfer is going to take roughly 60 hours total, and we've already spent around 24h of that, so, we have 36h left. But I did that all in my head, we can ask more of Qalc yet! Let's make another variable, for that total estimated time:

> total=(now-start)/x = (2996538438607 bytes)/(7258298064 KiB)
  save(((now   start) / x) = ((2996538438607 bytes) / (7258298064
  kibibytes)); total; Temporary; ; 1)  
  2 d + 11 h + 14 min + 38.22 s

And we can plug that into another formula with our start time to figure out when we'll be done!

> start+total
  start + total   "2025-02-10T03:28:52"
> start+total-now
  start + total   now   1 d + 11 h + 34 min + 48.52 s
> start+total-now to h
  start + total   now   35 h + 34 min + 32.01 s

That transfer has ~1d left, or 35h24m32s, and should complete around 4 in the morning on February 10th. But that's icing on top. I typically only do the cross-multiplication and calculate the remaining time in my head. I mostly did the last bit to show Qalculate could compute dates and time differences, as long as you use ISO timestamps. Although it can also convert to and from UNIX timestamps, it cannot parse arbitrary date strings (yet?).

Other functionality Qalculate can:

• Plot graphs;
• Use RPN input;
• Do all sorts of algebraic, calculus, matrix, statistics, trigonometry functions (and more!);
• ... and so much more!

I have a hard time finding things it cannot do. When I get there, I typically need to resort to programming code in Python, use a spreadsheet, and others will turn to more complete engines like Maple, Mathematica or R. But for daily use, Qalculate is just fantastic. And it's pink! Use it!

Further reading and installation This is just scratching the surface, the fine manual has more information, including more examples. There is also of course a qalc(1) manual page which also ships an excellent EXAMPLES section. Qalculate is packaged for over 30 Linux distributions, but also ships packages for Windows and MacOS. There are third-party derivatives as well including a web version and an Android app.

Updates Colin Watson liked this blog post and was inspired to write his own hacks, similar to what's here, but with extras, check it out!

• Figure 21 ( which programming languages to code AI ) has more bars in the chart than labels.
• Figure 22 ( which Java AI libraries ) clearly is nonsense, because, e.g.:
  • top-ranked JavaML is not even on maven, and has not received updates since 2016
  • second-ranked Deep Java Library (DIL) would correctly be abbreviated DJL
  • third-ranked OpenCL is not a Java library, but a language on its own
  • fourth-ranked is PyTorch. Clearly not Java either
  • fifth-ranked is Jvector. Which is a database
  • seventh-ranked is TensorFlow, again not Java
  • 11th Apache Jena is a RDF app framework, not AI
  • 13th Apache Mahout is dead, and has become a Python Quatum Computing POC, Qunat

Participants were offered token compensation for their participation.

Changes in version 0.0.2 (2025-02-07)

• Complete DESCRIPTION and README.md following initial CRAN upload

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can sponsor me at GitHub.

Sample configuration file for the SteamOS updater

1. A copy is actually kept under /etc/previous to give the user the chance to recover files if necessary, and up to five previous snapshots are kept under /var/lib/steamos-atomupd/etc_backup