<s>
Perforce	B-Application
Jam	I-Application
was	O
an	O
open-source	B-Application
build	B-Application
system	I-Application
developed	O
by	O
Christopher	O
Seiwald	O
of	O
Perforce	B-General_Concept
Software	I-General_Concept
.	O
</s>
<s>
It	O
was	O
used	O
as	O
a	O
replacement	O
for	O
make	B-Application
.	O
</s>
<s>
Its	O
primary	O
feature	O
was	O
its	O
ability	O
to	O
express	O
build	O
patterns	O
in	O
an	O
imperative	B-Application
language	I-Application
which	O
supported	O
structured	O
namespaces	O
(	O
similar	O
to	O
Pascal	B-Application
records	B-General_Concept
)	O
and	O
simple	O
lists	O
.	O
</s>
<s>
Jam	O
could	O
be	O
used	O
with	O
autoconf	B-Application
,	O
although	O
it	O
was	O
often	O
not	O
necessary	O
because	O
of	O
Jam	O
's	O
portability	B-Architecture
features	O
.	O
</s>
<s>
Perforce	B-Application
Jam	I-Application
ran	O
on	O
Unix	B-Application
(	O
including	O
many	O
clones	O
)	O
,	O
OpenVMS	B-Operating_System
,	O
Windows	B-Device
NT	I-Device
(	O
including	O
Windows	B-Application
2000	I-Application
and	O
Windows	B-Application
XP	I-Application
)	O
,	O
Mac	B-Application
OS	I-Application
,	O
and	O
BeOS	B-Application
.	O
</s>
<s>
It	O
was	O
also	O
possible	O
to	O
configure	O
it	O
to	O
work	O
on	O
Windows	B-Application
9x	I-Application
using	O
MinGW	B-Application
or	O
Cygwin	B-Language
.	O
</s>
<s>
The	O
company	O
announced	O
that	O
version	O
2.6	O
released	O
in	O
August	O
2014	O
was	O
the	O
last	O
Perforce	B-Application
Jam	I-Application
release	O
.	O
</s>
<s>
FT	O
Jam	O
is	O
a	O
popular	O
variant	O
and	O
fully	O
backward	B-General_Concept
compatible	I-General_Concept
,	O
although	O
its	O
features	O
are	O
being	O
integrated	O
into	O
Perforce	B-Application
Jam	I-Application
.	O
</s>
<s>
Users	O
of	O
FT	O
Jam	O
often	O
refer	O
to	O
Perforce	B-Application
Jam	I-Application
as	O
"	O
Classic	O
Jam	O
"	O
.	O
</s>
<s>
The	O
Boost	B-Language
C++	I-Language
Libraries	I-Language
is	O
using	O
a	O
Jam	O
variant	O
called	O
"	O
Boost.Jam	O
"	O
(	O
or	O
"	O
BJam	O
"	O
)	O
.	O
</s>
<s>
Haiku	O
Jam	O
is	O
a	O
custom	O
fork	O
of	O
Perforce	B-General_Concept
's	O
Jam	O
used	O
by	O
Haiku	O
.	O
</s>
<s>
JamPlus	O
adds	O
new	O
features	O
to	O
Jam	O
and	O
integrates	O
a	O
number	O
of	O
patches	O
from	O
the	O
Jamming	O
mailing	O
list	O
and	O
the	O
Perforce	B-General_Concept
Public	O
Depot	O
.	O
</s>
<s>
Jambase	O
is	O
"	O
smart	O
"	O
and	O
knows	O
,	O
for	O
instance	O
,	O
that	O
if	O
a	O
header	B-Language
file	I-Language
is	O
modified	O
,	O
all	O
files	O
that	O
include	O
it	O
must	O
be	O
rebuilt	O
.	O
</s>
<s>
Unlike	O
with	O
makefiles	O
,	O
the	O
writer	O
of	O
the	O
Jamfile	B-Application
need	O
not	O
manage	O
these	O
dependencies	B-Application
,	O
only	O
list	O
the	O
source	O
code	O
files	O
themselves	O
.	O
</s>
<s>
Jambase	O
is	O
notorious	O
among	O
Jam	O
users	O
for	O
its	O
bugs	B-Error_Name
and	O
the	O
infrequency	O
with	O
which	O
fixes	O
are	O
integrated	O
into	O
the	O
distribution	O
,	O
though	O
few	O
bugs	B-Error_Name
are	O
critical	O
.	O
</s>
<s>
Jam	O
was	O
open-source	B-Application
.	O
</s>
