<s>
SpaceChem	B-Application
is	O
an	O
indie	O
puzzle	O
game	O
developed	O
by	O
Zachtronics	O
Industries	O
,	O
based	O
on	O
principles	O
of	O
automation	B-Application
and	O
chemical	O
bonding	O
.	O
</s>
<s>
In	O
the	O
game	O
,	O
the	O
player	O
is	O
tasked	O
to	O
produce	O
one	O
or	O
more	O
specific	O
chemical	O
molecules	O
via	O
an	O
assembly	O
line	O
by	O
programming	O
two	O
remote	O
manipulators	O
(	O
called	O
"	O
waldos	O
"	O
in	O
the	O
game	O
)	O
that	O
interact	O
with	O
atoms	O
and	O
molecules	O
through	O
a	O
visual	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
SpaceChem	B-Application
was	O
the	O
developer	O
's	O
first	O
foray	O
into	O
a	O
commercial	O
title	O
after	O
a	O
number	O
of	O
free	O
Flash-based	B-Operating_System
browser	O
games	O
that	O
feature	O
similar	O
puzzle-based	O
assembly	O
problems	O
.	O
</s>
<s>
The	O
game	O
was	O
initially	O
released	O
for	O
Microsoft	B-Application
Windows	I-Application
at	O
the	O
start	O
of	O
2011	O
via	O
Zachtronics	O
 '	O
own	O
website	O
.	O
</s>
<s>
Though	O
it	O
was	O
initially	O
rejected	O
for	O
sale	O
on	O
the	B-Application
Steam	I-Application
platform	I-Application
,	O
Valve	O
later	O
offered	O
to	O
sell	O
the	O
game	O
after	O
it	O
received	O
high	O
praise	O
from	O
game	O
journalists	O
;	O
further	O
attention	O
came	O
from	O
the	O
game	O
's	O
release	O
alongside	O
one	O
of	O
the	O
Humble	O
Indie	O
Bundles	O
.	O
</s>
<s>
SpaceChem	B-Application
was	O
incorporated	O
into	O
some	O
academic	O
institutions	O
for	O
teaching	O
concepts	O
related	O
to	O
both	O
chemistry	O
and	O
programming	O
.	O
</s>
<s>
In	O
SpaceChem	B-Application
,	O
the	O
player	O
takes	O
the	O
role	O
of	O
a	O
SpaceChem	B-Application
Reactor	O
Engineer	O
whose	O
task	O
is	O
to	O
create	O
circuits	O
through	O
which	O
atoms	O
and	O
molecules	O
flow	O
with	O
the	O
aid	O
of	O
waldos	O
to	O
produce	O
particular	O
batches	O
of	O
chemical	O
shipments	O
for	O
each	O
level	O
.	O
</s>
<s>
The	O
primary	O
game	O
mode	O
of	O
SpaceChem	B-Application
depicts	O
the	O
internal	O
workings	O
of	O
a	O
Reactor	O
,	O
mapped	O
out	O
to	O
a	O
10×8	O
regular	O
grid	O
.	O
</s>
<s>
As	O
such	O
,	O
the	O
player	O
is	O
challenged	O
to	O
create	O
a	O
visual	B-Language
program	I-Language
to	O
accept	O
the	O
given	O
inputs	O
,	O
disassemble	O
and	O
reassemble	O
them	O
as	O
necessary	O
,	O
and	O
deliver	O
them	O
to	O
the	O
target	O
output	O
areas	O
to	O
match	O
the	O
required	O
product	O
.	O
</s>
<s>
SpaceChem	B-Application
supports	O
downloadable	B-Protocol
content	I-Protocol
created	O
by	O
the	O
developers	O
themselves	O
,	O
and	O
user-submitted	O
puzzles	O
through	O
its	O
ResearchNet	O
service	O
.	O
</s>
<s>
Prior	O
to	O
SpaceChem	B-Application
,	O
Zach	O
Barth	O
,	O
the	O
designer	O
behind	O
Zachtronics	O
Industries	O
,	O
had	O
created	O
several	O
Flash-based	B-Operating_System
browser	O
games	O
with	O
automation	B-Application
puzzles	O
,	O
including	O
The	O
Codex	O
of	O
Alchemical	O
Engineering	O
where	O
the	O
player	O
had	O
to	O
place	O
and	O
program	O
manipulator	O
arms	O
to	O
construct	O
atoms	O
and	O
molecules	O
following	O
the	O
rules	O
of	O
alchemy	B-Language
.	O
</s>
<s>
SpaceChem	B-Application
took	O
about	O
a	O
year	O
with	O
a	O
team	O
of	O
seven	O
people	O
from	O
around	O
the	O
globe	O
to	O
create	O
:	O
Barth	O
was	O
responsible	O
for	O
design	O
and	O
production	O
,	O
Collin	O
Arnold	O
and	O
Keith	O
Holman	O
handled	O
the	O
programming	O
,	O
Ryan	O
Sumo	O
created	O
the	O
visuals	O
,	O
Evan	O
Le	O
Ny	O
the	O
music	O
,	O
Ken	O
Bowen	O
the	O
sound	O
and	O
Hillary	O
Field	O
created	O
the	O
game	O
's	O
narrative	O
.	O
</s>
<s>
The	O
team	O
used	O
the	O
C#	B-Application
language	O
built	O
on	O
the	O
Mono	B-Application
framework	I-Application
for	O
the	O
game	O
which	O
would	O
allow	O
for	O
easy	O
porting	O
to	O
other	O
platforms	O
beyond	O
Microsoft	B-Application
Windows	I-Application
.	O
</s>
<s>
Initially	O
,	O
they	O
had	O
considered	O
using	O
Microsoft	B-Device
XNA	I-Device
for	O
ease	O
of	O
porting	O
to	O
the	B-Operating_System
Xbox	I-Operating_System
360	I-Operating_System
,	O
but	O
later	O
opted	O
to	O
consider	O
other	O
release	O
platforms	O
,	O
requiring	O
them	O
to	O
switch	O
to	O
the	O
more	O
portable	O
Mono	B-Application
framework	I-Application
.	O
</s>
<s>
Based	O
on	O
the	O
feedback	O
that	O
players	O
had	O
made	O
on	O
sites	O
that	O
hosted	O
his	O
previous	O
Flash-based	B-Operating_System
games	O
,	O
Barth	O
designed	O
the	O
global-based	O
histograms	O
to	O
allow	O
players	O
to	O
check	O
their	O
solution	O
without	O
feeling	O
overwhelmed	O
by	O
the	O
top	O
players	O
as	O
would	O
be	O
normally	O
listed	O
on	O
a	O
leaderboard	O
.	O
</s>
<s>
He	O
also	O
tried	O
too	O
much	O
to	O
incorporate	O
a	O
theme	O
based	O
on	O
scientific	O
research	O
,	O
popularized	O
at	O
the	O
time	O
by	O
the	O
success	O
of	O
Portal	B-Application
.	O
</s>
<s>
He	O
instead	O
found	O
potential	O
players	O
were	O
scared	O
off	O
by	O
the	O
chemistry	O
aspect	O
even	O
though	O
the	O
game	O
had	O
little	O
connection	O
to	O
real	O
chemistry	O
;	O
a	O
colleague	O
had	O
once	O
suggested	O
to	O
Barth	O
that	O
if	O
the	O
game	O
was	O
named	O
SpaceGems	O
and	O
modeled	O
around	O
alchemy	B-Language
,	O
the	O
game	O
would	O
have	O
sold	O
twice	O
as	O
many	O
copies	O
.	O
</s>
<s>
SpaceChem	B-Application
was	O
released	O
on	O
January	O
1	O
,	O
2011	O
via	O
digital	O
download	O
from	O
the	O
Zachtronics	O
website	O
for	O
Microsoft	B-Application
Windows	I-Application
,	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
,	O
and	O
Linux	B-Application
computers	O
.	O
</s>
<s>
They	O
had	O
initially	O
sought	O
to	O
get	O
approval	O
from	O
Valve	O
to	O
sell	O
the	O
game	O
through	O
Steam	B-Application
,	O
but	O
Valve	O
refused	O
them	O
,	O
and	O
thus	O
opted	O
for	O
sale	O
from	O
their	O
own	O
website	O
.	O
</s>
<s>
Zachtronics	O
was	O
contacted	O
two	O
days	O
later	O
by	O
Valve	O
with	O
an	O
interest	O
to	O
add	O
it	O
to	O
Steam	B-Application
.	O
</s>
<s>
The	O
game	O
was	O
subsequently	O
made	O
available	O
on	O
Steam	B-Application
by	O
March	O
4	O
,	O
2011	O
,	O
and	O
later	O
on	O
GamersGate	O
on	O
March	O
17	O
,	O
2011	O
.	O
</s>
<s>
The	O
inclusion	O
of	O
the	O
game	O
on	O
Steam	B-Application
was	O
considered	O
by	O
Barth	O
to	O
be	O
the	O
largest	O
boost	O
to	O
sales	O
of	O
the	O
game	O
,	O
outweighing	O
any	O
other	O
distribution	O
method	O
they	O
had	O
.	O
</s>
<s>
SpaceChem	B-Application
received	O
a	O
free	O
update	O
in	O
late	O
April	O
2011	O
,	O
which	O
added	O
several	O
new	O
features	O
to	O
the	O
game	O
as	O
well	O
as	O
new	O
puzzles	O
.	O
</s>
<s>
The	O
patch	O
included	O
support	O
for	O
the	O
ResearchNet	O
puzzle	O
creation	O
and	O
sharing	O
system	O
,	O
and	O
for	O
the	O
Steam-enabled	O
version	O
,	O
support	O
for	O
achievements	O
and	O
leaderboards	O
specific	O
for	O
Steam	B-Application
friends	O
.	O
</s>
<s>
The	O
update	O
for	O
the	O
Steam	B-Application
version	O
also	O
included	O
a	O
small	O
set	O
of	O
puzzles	O
tied	O
in	O
with	O
Team	B-Application
Fortress	I-Application
2	I-Application
,	O
which	O
upon	O
completion	O
would	O
reward	O
the	O
player	O
with	O
a	O
decorative	O
item	O
they	O
could	O
use	O
within	O
Team	B-Application
Fortress	I-Application
2	I-Application
.	O
</s>
<s>
SpaceChem	B-Application
was	O
ported	O
to	O
the	O
iPad	B-Device
in	O
October	O
2011	O
,	O
using	O
touch	O
controls	O
instead	O
of	O
mouse	O
and	O
keyboard	O
to	O
manipulate	O
the	O
visual	B-Language
program	I-Language
.	O
</s>
<s>
An	O
Android	B-Application
port	O
was	O
released	O
in	O
July	O
2012	O
.	O
</s>
<s>
The	O
sandbox	O
mode	O
was	O
added	O
at	O
the	O
request	O
of	O
a	O
player	O
who	O
was	O
trying	O
to	O
explore	O
SpaceChem	B-Application
computational	O
abilities	O
.	O
</s>
<s>
This	O
same	O
user	O
was	O
able	O
to	O
demonstrate	O
a	O
brainfuck	B-Language
interpreter	O
within	O
SpaceChem	B-Application
,	O
claiming	O
that	O
the	O
visual	B-Language
programming	I-Language
language	I-Language
was	O
Turing	B-Algorithm
complete	I-Algorithm
.	O
</s>
<s>
According	O
to	O
The	O
Independent	O
Games	O
Developers	O
Association	O
,	O
schools	O
in	O
the	O
United	O
Kingdom	O
have	O
started	O
using	O
SpaceChem	B-Application
to	O
teach	O
students	O
fundamental	O
programming	O
concepts	O
.	O
</s>
<s>
The	O
success	O
of	O
SpaceChem	B-Application
led	O
to	O
several	O
companies	O
contacting	O
Zachtronics	O
to	O
develop	O
educational	O
titles	O
;	O
the	O
company	O
spent	O
about	O
two	O
years	O
working	O
with	O
Amplify	O
to	O
develop	O
three	O
"	O
edutainment	O
"	O
games	O
for	O
their	O
platform	O
before	O
they	O
returned	O
to	O
work	O
on	O
more	O
direct	O
entertainment	O
titles	O
,	O
but	O
used	O
the	O
opportunity	O
to	O
improve	O
on	O
their	O
in-game	O
teaching	O
mechanics	O
.	O
</s>
<s>
On	O
September	O
30	O
,	O
2012	O
,	O
SpaceChem	B-Application
was	O
the	O
featured	O
game	O
on	O
IndieGameStand	O
,	O
a	O
site	O
which	O
features	O
indie	O
games	O
with	O
a	O
pay-what-you-want	O
model	O
with	O
a	O
portion	O
of	O
the	O
proceeds	O
going	O
to	O
charity	O
.	O
</s>
<s>
On	O
October	O
25	O
,	O
2015	O
,	O
Zachtronics	O
announced	O
they	O
have	O
dropped	O
all	O
support	O
for	O
SpaceChem	B-Application
on	O
the	O
iOS	B-Application
and	O
OS	B-Operating_System
X	I-Operating_System
platform	O
.	O
</s>
<s>
The	O
reason	O
they	O
gave	O
was	O
due	O
to	O
the	O
complexity	O
of	O
the	O
Mono	B-Application
package	O
for	O
future	O
support	O
.	O
</s>
<s>
SpaceChem	B-Application
was	O
generally	O
well	O
received	O
by	O
critics	O
,	O
with	O
an	O
aggregate	O
Metacritic	O
score	O
of	O
84	O
out	O
of	O
100	O
from	O
its	O
Microsoft	B-Application
Windows	I-Application
release	O
.	O
</s>
<s>
Gamasutra	O
's	O
Margaret	O
Robertson	O
praised	O
SpaceChems	B-Application
gameplay	O
,	O
contrasting	O
it	O
with	O
other	O
open-ended	O
activities	O
as	O
it	O
offers	O
the	O
opportunity	O
for	O
the	O
player	O
to	O
be	O
as	O
creative	O
as	O
they	O
want	O
to	O
be	O
within	O
the	O
minimal	O
ruleset	O
required	O
of	O
each	O
puzzle	O
.	O
</s>
<s>
Edge	O
said	O
"	O
The	O
triumph	O
of	O
SpaceChem	B-Application
is	O
that	O
overcoming	O
these	O
situations	O
is	O
more	O
a	O
case	O
of	O
inventing	O
a	O
solution	O
than	O
discovering	O
one.	O
"	O
</s>
<s>
Team	O
Fortress	O
creator	O
Robin	O
Walker	O
recommended	O
"	O
SpaceChem	B-Application
"	O
on	O
Steam	B-Application
,	O
calling	O
it	O
"	O
Pretty	O
much	O
the	O
greatest	O
game	O
ever	O
made	O
"	O
.	O
</s>
<s>
Gamasutra	O
named	O
SpaceChem	B-Application
the	O
best	O
indie	O
game	O
of	O
2011	O
.	O
</s>
<s>
Barth	O
stated	O
that	O
with	O
sales	O
of	O
SpaceChem	B-Application
,	O
he	O
was	O
able	O
to	O
quit	O
his	O
job	O
at	O
Microsoft	O
and	O
run	O
his	O
development	O
company	O
full-time	O
.	O
</s>
<s>
Ryan	O
Sumo	O
,	O
the	O
freelance	O
artist	O
for	O
the	O
game	O
,	O
gained	O
recognition	O
in	O
the	O
industry	O
and	O
went	O
on	O
to	O
help	O
develop	O
the	O
art	O
for	O
Prison	B-Application
Architect	I-Application
.	O
</s>
