►
From YouTube: Getting Started with MetaMask Snaps
Description
Visit the https://archive.devcon.org/ to gain access to the entire library of Devcon talks with the ease of filtering, playlists, personalized suggestions, decentralized access on IPFS and more.
https://archive.devcon.org/archive/watch/6/getting-started-with-metamask-snaps/index
[MetaMask Snaps](https://bit.ly/3u8bDKh) is the next phase in [MetaMask](https://metamask.io)'s evolution. First previewed at Devcon V in 2019, we are now focused on growing the Snaps platform and ecosystem, and new features are added every month.
In this workshop, you'll build a Snap from start to finish with the MetaMask Snaps dev team. In the process, you'll learn about all the features you can make use of for Ethereum, Layer 2's, zero knowledge cryptography, and beyond.
Speaker(s): Erik Marks
Track: Developer Infrastructure
Keywords: wallets,dapps,applications
Follow us: https://twitter.com/efdevcon, https://twitter.com/ethereum
Learn more about devcon: https://www.devcon.org/
Learn more about ethereum: https://ethereum.org/
Devcon is the Ethereum conference for developers, researchers, thinkers, and makers.
Devcon 6 was held in Bogotá, Colombia on Oct 11 - 14, 2022.
Devcon is organized and presented by the Ethereum Foundation, with the support of our sponsors. To find out more, please visit https://ethereum.foundation/
A
A
I'm
Eric
marks
I
am
the
lead
engineer
of
metamask
snaps
at
this
Workshop
is
called
getting
started
with
metamask
snaps
I
realize
we
have
some
Wi-Fi
ishma
since
2018
snaps
was
first
announced
as
a
concept
three
years
ago,
at
Devcon
in
Osaka,
so
I
know
we
have.
We
have
some
returning
guests
with
us
today
in
the
room,
and
you
know
since
then,
lots
of
things
happened.
A
Covet
happened,
2020
happened,
but
since
2021
we've
been
working
on
snaps
full-time
at
metamask,
and
since
the
beginning
of
this
year
we
have
been
in
a
developer
release
via
our
Canary
version
of
the
metamask
extension
called
metamask
flask,
and
this
Workshop
is
basically
like
the
sort
of
snaps
101.
How
do
you
get
started
like
developing
a
snap
at
using
one
of
the
newer
apis
that
we
developed?
A
If
you
read
the
instructions,
there's
a
custom
build
of
metamask
to
download
because
we
haven't
shipped
this
API
in
production.
Yet
it's
coming
in
the
next
few
weeks,
but
before
continuing,
we
need
to
talk
a
little
bit
about
what
is
metamask
Maps
and
we're
gonna
and
we're
gonna
start
from
the
very
ground
level
and
build
up
from
there,
and
so
metamask,
as
all
of
you
probably
know,
is
a
non-custodial
cryptocurrency
wallet
for
ethereum.
You
enter
your
secret
recovery
phrase
into
metamask.
A
You
can
derive
your
at
your
keys
and
your
externally
owned
accounts
and
it
will
manage
those
keys
for
you.
Encrypt
them
with
a
password
metamask
allows
you
to
interact
with
ethereum
via
an
RPC
endpoint
by
default.
We
use
our
friends
at
inferior,
but
you
can
add,
whichever
ones
that
you
want
and
that
allows
you
to
do
stuff,
like
you
know,
send
transactions
from
account,
one
to
account
two.
A
What
about
you
know?
Zero
knowledge,
applications
and
non-etherium
cryptography
so
like
things
that
use
curves
other
than
SEC
p256k1,
and
that's
just
like
a
a
sample
of
the
things
that's
being
built
in
ethereum
that
we
don't
support
out
of
the
box
and
that
you
know
doesn't
even
get
into
Cosmos
polka
dots,
Avalanche
Solana,
whatever
in
addition
to
to
those
things,
and
so
it
is,
we
believe
basically
impossible
and
I
think
you
know
practically
like
empiric
like
I
observe
this
I
don't
predict
it.
A
It
is
impossible
for
any
single
organization
to
add
support
to
develop
the
domain,
expertise
to
understand
all
of
these
different
protocols
and
Primitives,
and
then
also
to
develop
the
code
and
maintain
the
you
know.
Unimaginably
large
code
base
that
it
would
take
to
actually
create
user
experience
for
all
of
the
things
that
are
being
built
in
web
3.
and
metamask.
A
Just
in
the
past
week,
over
the
course
of
eth
Bogota
and
some
and
a
hacker
house
that
we
co-sponsored
with
bit
Dao
in
game.
Seven
hackers
have
developed
a
CK,
nullifier
snap
transaction
Securities
map,
an
account
account
activity,
notifications
and
a
smart
contract
account
wallet
or
a
smart
contract.
A
Account
Support,
all
in
metamask,
all
using
snaps
and
and
snaps
currently
in
developer
releases,
include
starknet
filecoin
at
Bitcoin,
R,
weave
and
many
more
and
so,
and
here
I'll,
just
briefly
stop
to
say
that,
like
we're,
all
like
this,
isn't
a
developer
release.
So
the
reason
we
keep
it
in
the
channel
is
because
we
don't
it's
not
quite
ready
to
be
pushed
for
it
to
be
pushed
to.
A
You
know
the
tens
of
millions
of
people
that
use
metamask
on
a
daily
basis,
but
that
is
our
goal
in
the
upcoming
year
and
we'll
get
to
that
in
a
bit,
and
so
we-
and
so
we
believe
that
this
illustrates
that
snaps
is
the
gateway
to
all
of
web
3.
by
turning
the
wallet
itself
into
an
application
platform.
A
I
was
I
was
too
busy
trying
to
get
my
Wi-Fi
to
work
to
clear
out
all
of
this
stuff,
but
we'll
get
started
here
in
a
second,
and
so
so,
as
I
mentioned.
The
first
thing
that
we
need
to
do
is
add
a
custom
build
of
metamask
flask
to
the
browser,
and
my
visibility
is,
is
the
size
of
like
the
editor
and
the
text
and
everything
good
so
far,
okay,
yeah,
please,
please
holler
at
me.
A
If
not
and
the
way
you
add
a
custom
build
to
Chrome,
is
you
simply
get
your
build
from
wherever
from
wherever
that
lives?
And
you
just
drag
and
drop
it
in
your
browser
needs
to
be
in
developer
mode
in
order
for
that
to
work
so
and
be
advised
that
developer
mode,
like
exposes
your
extensions
to
certain
kinds
of
malware,
so
you
know,
don't
put
your
don't
put
Main
in
developer
mode
and
we're
just
going
to
go
through
onboarding
here
super
quickly,
foreign.
A
And
Wi-Fi
permitting,
we
should
be
good
to
go.
Okay,
yes,
all
right!
So
now,
I've
set
up
a
version
of
flask,
and
so
the
only
thing
you'll
notice,
that's
like
immediately
different
with
flask,
is
that
the
onboarding
is
slightly
different
and
we
have
a
purple
Fox
to
distinguish
it
from
the
regular
Orange
Box.
A
And
the
next
thing
we're
gonna
do
is
I've
already
done
this,
but
the
next
step
is
to
create
a
new
GitHub
repository
using
the
template,
snap
mono
repo.
So
this
monorepo
is
as
a
template
that
contains
two
things:
a
two
or
two
sub-repositories
or
packages,
a
website
and
the
actual
snap
itself,
and
things
are
yeah
they're
kind
of
loading,
but
once
you've
pulled
that
down
and
run
yarn
install,
we
can
see
here
that
should
still
be
good,
that
we
have
in
our
packages.
A
Which
should
hopefully
not
need
too
much
network
access.
Great,
thank
you,
and
so
this
is
the
template,
snap
interface,
and
so
you
see
we
have
it.
We
have
everything
hosted
on
localhost
and
the
first
thing
we
need
to
do
is
connect
to
our
snap,
and
so
first,
when
you
install
a
snap,
you
get
a
permission
request
from
the
website
that
that
made
the
request
and
it's
basically
saying
hey
I-
have
the
website
at
this
URL
wants
to
talk
to
at
this
particular
snap
and
during
local
development.
A
Snaps
are
just
identified
by
the
localhost
URL,
where
they're
hosted
just
out
of
convenience,
and
once
we've
accepted
that
permission
request,
then
metamask
will
go
and
fetch
the
snap
source
code
and
it's
manifest
and
then
ask
for
its
permissions,
and
so
here
we
see
that
this
snap
again
identified
by
its
localhost
URL.
That
wants
to
display
confirmations
inside
of
metamask
and
we're
going
to
say,
okay
to
that
and
to
try
out
this
functionality,
oops
excellent.
A
That's
it.
That's
it
folks,
a
snap,
a
snap!
Everyone
get
a
look,
get
a
look!
It's
showing
a
confirmation!
Oh
goodness!
Yes,
yes,
yes,
okay,
it's
real
yeah
yeah!
So
so
what
happened
here
is
I
was
gonna.
Do
a
little
I
was
going
to
mess
around
with
this
notification
a
little
bit
but
or
confirmation
rather,
but
we're
not
gonna
do
that.
A
A
A
If
we
go
back
to
the
snap,
that
is
the
only
method
that
we
support
and
that
just
causes
this
confirmation
to
be
displayed
now,
if
things
like
continue
working
a
little
bit
better
than
they
were
doing
some
minutes
ago,
we're
going
to
take
this
snap
and
turn
it
into
a
transaction
Insight
snap,
and
if
we
briefly
return
here
so
we've.
Basically,
we've
demonstrated,
like
we've
gotten
a
snap
running
and
now
it's
time
to
like
replace
its
confirmation
permission
with
this
transaction
Insight
permission
and
all
that
this
permission
does.
A
A
Yes,
okay
and
we're
also
just
going
to
add
a
little
bit
of
validation
to
make
sure
that
the
transaction
is
of
a
type
that
we
can
understand
because,
like
you
know,
we're
writing
a
specific
Insight
snap
that
that
uses
our
particular
domain
knowledge.
And
so
we
need
the
transaction
to
look
at
a
particular
way.
A
B
A
B
A
So
we
have
a
from
address.
The
to
address
is
going
to
be
the
address
of
a
contract
that
is
in
fact
deployed
to
mainnet,
but
that
will
reject
any
transaction
that
we
accidentally
sent
to
it.
I
just
happen
to
know
this
to
be
the
case,
we're
not
sending
it
anything
in
terms
of
value
and
then
the
data
that
we're
going
to
send
it
to
start
with
is
just
going
to
be
some
dummy
like
0x1,
and
that
is
basically
all
right
and
now
we're
going
to
have
now.
A
A
A
A
A
And
so
here
the
this
API
endpoint.
That's
simply
just
like
the
the
four
byte
API
endpoint
that
we're
going
to
call
it
has
a
single
query
parameter,
which
is
the
hexadecimal
like
four
byte
signature
of
the
of
the
contract,
call
the
call
data,
and
then
we
have
just
a
useful
type
that
we
will
use
when
we
parse
the
results
once
once
we
get
them
this
network
permitting,
and
so
actually
before
I
forget
to
do
this
I'm
going
to
swap
out
this
dummy
value
into
something
real.
A
Let's
see,
transaction
constants
Dot
update
withdrawal
account,
so
these
are
just
some.
These
are
just
like
some
encoded
contract
calls
that
we
to
save
time
we
encoded
before
this
Workshop,
and
so
next
we
want
to
fetch
data
from
four
bytes,
and
that
is
going
to
start
with.
A
fetch
call
await
fetch
all
right.
Are
we
done?
No
we're
not
done,
because
we
need
to
parse
the
transaction
data
first
and
we
are
going
to
do
let's
see
function.
Signature
is
going
to
be
equal
to
all
right.
A
B
B
A
B
A
Then
once
we
have
that
result,
so
the
thing
there's
one
thing:
we
have
to
deal
with
we're
going
to
extract
the
actual
text,
signature
of
the
of
the
function
call
and
because
four
bytes
is
not
a
very
big
space.
There
are
a
lot
of
collisions,
so
it
might
return
multiple
results.
Anyone
who's
dealt
with
this
with
four
byte
in
practice,
is
probably
familiar
with
this
problem
and
we're
just
going
to
pick
the
oldest
one,
because
we
need
to
pick
something
and
so
we're
gonna
see
function.
A
B
B
A
A
So
going
back
we're
going
to
need
to
reconnect
because
we
modified
the
snap.
The
live
reload,
unfortunately,
doesn't
go
all
the
way
into
the
extension
someday
we're
going
to
be
able
to
do
that.
But
now
we
see
that
the
permissions
are
different.
We
have
access
to
the
internet
as
one
of
the
permissions
now
and
we're
going
to
go
ahead
and
approve
and
install
so
far
so
good,
and
then,
let's
see
what
happens
now,.
A
A
B
A
A
B
A
Hey
there,
it
is
there,
it
is
the
function,
signature,
the
function,
signature
and
for
for
our
final
trick,
we're
going
to
get
a
little
bit
fancier
we're
also
going
to
decode
the
actual
parameters
that
are
encoded
in
the
call
data
as
well.
Just
because
we
can-
and
in
order
to
do
that,
we
are
going
to
add
a.
A
A
This
ABI
utils
package
has
an
encode
and
a
decode
function
which
allows
you
to
decode
and
encode
call
data,
and
it
has
it
returns,
values
that
are
not
Json
serializable
and
that
doesn't
work
because
the
transaction
insights
need
to
be
Json
serializable.
So
this
is
just
a
function
that
handles
that
and
we're
not
going
to
worry
about
what
it
does
in
detail
at
the
code
parameters,
and
so
we
are
going
to
import
encode
from.
A
My
ID
is
leaking
that
I've
already
done
this
earlier
today
and
then
we
are
going
to
split
right,
because
if
you
you'll
recall
that
this
looks
something
like
a
function,
name
type,
one
comma
type,
so
we're
just
going
to
extract
this
substring
split
on
the
commas
and
then
we're
going
to
have
the
parameter
types
and
the
reason
we
need.
That
is
because
that
is
an
input
to
the
decode
function.
A
A
Hey
parameters
address
and
Boolean,
just
as
we
would
expect
from
the
function
type
and
so
now,
and
so
this
is
so
obviously
like
we're
not
going
super
deep
and
like
just
seeing
the
parameters
here
is
not
super
useful
but
the.
But
the
point
that
that
we're
illustrating
here
is
that,
like
you
know,
this
snap
is
pretty
much
aside
from
hitting
four
byte
like
it's
a
it's
self-contained.
A
C
C
A
Right
and
so
the
so
we
are
trying
to
create
specifications
for
like
the
Manifest
and
the
apis
that
we
ship
and
so
on.
We
have
a
lot
of
work
that
I
won't
have
time
in
progress
that
I
won't
have
time
to
talk
about,
but
like
using
something
like
wallet.
Connect
V2
to,
like
you
know,
are
just
like
the
the
dapple
just
ask
for
the
network
that
it
wants
and
then
metamask
will
go
and
find
the
snap
that
supports
it
and
add
it
as
part
of
like
the
connection
flow.
A
So
you
don't
have
to
like
call
a
specific
snap
in
order
to
interact
with
it
and
so
we're
trying
to
create
specifications
for
those
things
and
I
can't
talk
like
really
about
concrete
plans
at
this
point,
but
personally,
like
my
I,
would
love
to
see
snaps
become
like
an
open
standard
and
like
for
there
to
be
like
an
open
source
like
wallet
kernel
or
something
that,
like
others,
can
build
on
in
the
future.
Yeah
sure
and
I
think
I
saw
you
next
time.
A
A
As
you
look
who
recommends
this,
how
many
reviews
does
it
have?
How
many?
How
long
has
it
existed?
And
so
we
so
that's
like
why
we
want
and
need
a
market
place
to
exist
in
order
for
it
to
scale
to
users
without
them
getting
scammed,
and
until
we
get
to
that
point,
our
first
release
is
probably
going
to
have
like
a
finite
set
of
snaps.
That,
like
at
least
you
know,
we
can
we're
confident.
You
know
our.
A
You
know
we're
implemented
rigorously
if
they're
managing
keys,
they
they
were
perhaps
audited
and,
like
we
know,
they're
not
like
outright
trying
to
steal
your
stuff
but
like,
but
preventing
scams
in
a
like
permissionless
application.
Ecosystem
is
not
a
fully
solvable
problem,
but
we
think
by
building
but
I,
but
but
by
investing
in
the
community
and
then
like
a
Marketplace.
We
can
get
there.
Foreign
next
question.
A
So
mobile,
so
we've
mobile
is
a
TBD.
It's
it's
going,
we're
we're
working
on
it
at
no
timelines
to
announce
as
of
yet
no
they
so
so
they
are
like
the
execution
environment
is
the
same.
The
goal
is
for
a
snap
to
be
unable
to
tell
if
it's
executing
in
the
browser
in
the
server
on
a
mobile
device
on
an
abacus
like
shouldn't
matter
yeah,
that's
the
that's
the
guarantee!
Yes,.
A
A
That
is
a
a
great
question
kind,
stranger,
and
so
we
have
like
in
the
in
the
hack
MD.
There
are
some
links
at
the
top
that
lead.
You
probably
yeah,
no
yeah,
it's
locked
whatever.
No,
it's
on
the
hack
MD,
which
is
on
the
slides,
which
are
accessible
through
the
schedule
like
on
on
Devcon,
but
that
metamask
has
a
repository
called
snaps
monorepo
that
snaps
Dash
mono
repo
and
the
discussions
in
there
are
a
great
place
to
get
started.