<s>
Scwm	B-Device
or	O
Scheme	B-Device
Constraints	I-Device
Window	I-Device
Manager	I-Device
is	O
a	O
window	B-Application
manager	I-Application
for	O
the	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
.	O
</s>
<s>
Its	O
main	O
features	O
are	O
dynamic	O
configurability	O
and	O
programmability	O
via	O
a	O
language	O
based	O
on	O
GNU	B-Application
Guile	I-Application
and	O
the	O
embedded	O
arithmetic	O
Cassowary	B-Application
constraint	I-Application
solver	I-Application
.	O
</s>
<s>
In	O
real	O
time	O
,	O
the	O
Cassowary	B-Application
constraint	I-Application
solver	I-Application
re-solves	O
the	O
system	O
of	O
equalities	O
and	O
inequalities	O
and	O
applies	O
the	O
new	O
mathematical	O
solution	O
to	O
the	O
on-screen	O
layout	O
,	O
animating	O
windows	O
to	O
their	O
new	O
positions	O
.	O
</s>
<s>
Scwm	B-Device
,	O
like	O
many	O
window	O
managers	O
,	O
began	O
from	O
Fvwm	B-Device
,	O
another	O
highly	O
configurable	O
window	B-Application
manager	I-Application
.	O
</s>
<s>
Scwm	B-Device
development	O
has	O
been	O
stagnant	O
since	O
2000	O
when	O
Badros	O
completed	O
his	O
Ph.D.	O
at	O
the	O
University	O
of	O
Washington	O
;	O
the	O
last	O
updates	O
to	O
the	O
git	B-Application
repository	O
have	O
focused	O
on	O
maintaining	O
compatibility	O
with	O
Guile	O
2.0.x	O
.	O
</s>
