►
From YouTube: Smart Transactions by Vlad Zamfir | Devcon Bogotá
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 Swarm, IPFS and more.
https://archive.devcon.org/archive/watch/6/smart-transactions/
Smart Transactions act as if they know how they are being situated and whether they are being treated fairly.
With context dependent semantics, uncanny awareness of the future, and mid-execution access to actual and virtual services, smart transactions challenge us to elaborate on Ethereum’s transactional semantics.
Speaker(s): Vlad Zamfir
Skill level: Intermediate
Track: Opportunity & Global Impact
Keywords: Transactions,MEV,time
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
Who
said
hi
just
now,
I
didn't
hear
hi
all
right.
Oh
great!
Thank
you
so
today,
I'm
going
to
share
some
exciting
research
that
I've
been
doing
I,
don't
know
for
the
greater
part
of
the
last
six
months,
eight
months,
nine
months,
I,
don't
know
most
of
this
year,
not
not
that
this
is
the
only
research
I've
done.
This
is
just
the
most
exciting
stuff,
the
stuff
that
I
want
to
blow
your
mind
with
right
now.
So.
A
Let
me
just
take
out
my
notes,
just
in
case
I
get
there
and
then
I
need
a
refresher.
All
right,
hey
everyone,
so
smart
transactions
sounds
great.
It
is
a
prophecy
of
a
new
paradigm.
It's
basically
a
prophecy,
because
it's
not
something
like
I
decided
I'm,
not
like
imposing
this
on.
You
guys,
I'm,
like
making
a
prediction
that
you're
going
to
agree
with
me
is
like
sort
of
a
sound
prediction
and
then
the
only
thing
they
might
be
imposing
is
accelerating
the
timeline
which
is
sort
of
maybe
my
fault,
if
I'm
accelerating
it.
A
A
Basically
ethereum
transactions
will
become
smart,
which
means
yeah,
they're,
already
programmable
network,
but
they're
going
to
become
context
aware
in
this
way.
That's
like
characteristic
of
smart
products
that,
like
sort
of
like
you,
should
you
know
you
go,
you
walk
beside
them
and
then
they
start
like
breathing
and
like
knowing
what
you're
about
to
do-
and
you
know
they
sort
of
like
act,
smart
in
a
way,
that's
sort
of
more
than
just
programmable
network,
but
actually
like
they're,
they're
reactive
to
their
context
and
basically
that
means
sort
of
over
their
actual
impossible
Futures.
A
In
this
context,
and
also
over
their
over
like
this,
this
their
context
and
we'll
get
into
that
a
little
more
detail,
but,
like
today,
relatively
speaking,
let
me
say
that
transactions
are
dumb
and
blind.
Basically,
transactions
today
are
not
smart
and
they
will
become
smart
in
the
sense
of
like
smart
products,
which
is
like
a
kind
of
kind
of
research
in
product
design,
where
you
try
to
make
products
like
yeah,
programmable,
networked
and
reactive
to
their
contacts.
In
order
to
you
know,
in
order
that
they
act
right
depending
on
what's
Happening
to
them.
A
A
What
does
this
transaction
mean
because,
like
all
the
different
possible
ways,
it
could
be
executed
in
different
context,
and
so
especially,
what
does
it
mean
if
it's
not
just
sort
of
included
in
a
block
in
this
sort
of
natural,
simple
way
that
we
were
taught
in
the
white
paper
and
like
all
the
white
papers?
Even
so?
A
Actually,
when
people
when
the
transaction
pool
changes
when
the
way
people
order
them
and
blocks
changes,
it
changes,
in
fact,
the
transaction
semantics
and
so
and
they're
going
to
become
aware,
basically
at
first
slowly
and
then
and
then
a
lot
and
any
of
these
search
awareness
basically
will
start
and
is
starting
out
as
a
sort
of
really
minor
little
hacks.
And
it's
going
to
become
sort
of
much
more
much
more
aware.
So,
basically,
today
you
know
you
might
pay
out
Nev
in
a
favorable
outcome
in
the
future.
A
You'll
be
much
more
actively
and
much
less
packively,
interacting
with
the
search
in
order
to
get
better
performance
and
sort
of
a
better,
even
understanding
of
how
your
transaction
is
being
treated
during
the
transaction,
Zone
validation.
So
that
was
the
prophecy
basically
like,
because
this
same
pressure
by
Mev
transaction
is
going
to
become
smart.
The
semantics
are
going
to
be
totally
different
than
what
we
recognize
today,
because
basically
well
I
mean
I'll
get
I'll,
get
to
exactly
like
how
and
why
that's
like
a
secured
prophecy
and
not
like
a
speculation.
A
A
A
Who
was
supposed
to
take
all
the
med
to
Searchers,
who
are
supposed
to
be
like
sort
of
the
good
guys
protecting
your
transactions
and
giving
them
the
ability
to
influence
the
block
outcome
without
just
sort
of
this
pure
extractive
politics?
More,
like
you
know,
we
pay
for
the
thing
to
win.
As
long
as
we
win
the
auction,
you
know
and
we're
providing
a
good
bundle.
A
That's
that's
good,
and
then
there's
also
this
sort
of
really
really
I
mean
nascent
kind
of
good
map,
which
is
like
the
saving
and
out
of
gas
exceptions,
which
is
sort
of
like
a
really
classic
thing
that,
like
Mev,
was
sort
of
built
for
from
the
start.
We're
basically
like
sort
of
the
space
really
was
for
Traders,
who
were
getting
wrecked
in
this
gas
price
auction,
and
so
the
gas
production
became
Mev.
And
then
there
was
a
good
Mad.
A
A
This.
This
year,
right,
I
ran
again
got
into
the
AV
space.
Basically,
when
I
realized
that
there's
this
thing
called
Mev
time,
which
is
like
sort
of
the
time
when
the
search
is
happening
when
the
time
when
the
search
for
this,
like
bundle
or
block,
is
happening
where
you
can
actually
interact
with
ethereum
transactions
in
a
sort
of
on
conventional
way.
A
Basically,
rather
than
sort
of
only
having
you
know,
interactions
with
transactions,
you
can
actually
interact
as
the
Searcher
with
the
transactions
directly.
Basically
by
you
know,
the
Searchers
have
been
adding
their
own
transactions
to
bundles
and
interacting
with
them
to
like
sort
of
take
our
profits
in
the
normal
way,
but
sort
of
to
directly
interface
with
them
via,
like
an
I
o
interface,
where
you
just
like
load
values
and
they
read
values,
it
really
opens
up
the
ethereum
transactions
to
a
credible
sort
of
semantics
by
basically
letting
you
interrupt.
A
Transaction
flow
do
some
stuff
and
then
continue
transaction
flow
as
the
Searcher.
In
a
way
where
you
can
sort
of
update
Oracle
values
many
times
within
the
trace
of
a
transaction,
you
can
do
all
sorts
of
operations
in
the
middle
of
a
transaction
and
sort
of
in
some
way
violating
atomicity,
but
in
some
way
it's
not
because,
ultimately,
you
still
have
the
same.
A
You
know
bundle
of
transactions
just
that
the
bundle
was
set
up
in
a
way
where
the
earlier
transactions
are
put
in
as
a
function
of
like
what
happened
in
the
middle
of
the
other
ones.
So
it's
sort
of
really
just
Mev
time.
Interaction
with
transactions
really
opens
up
non-deterministic
semantics
of
the
evm.
A
Now,
instead
of
having
like
you,
just
literally,
have
the
evm
choose
arbitrarily
and
then,
like
your,
the
Searcher
tells
you
what
you
chose
and
they
have
like
an
incentive,
if
you
tip
them
good,
to
choose
the
right
thing
and
that
actually
not
just
lets.
You
take
advantage
of
these
Magic,
not
her
music
choices,
but
lets
you
have
more
information
in
the
transaction
than
you
than
you
could
before.
You
should
literally
just
give
them
anything
with
like
an
oracle
at
it.
A
Maybe
time
during
the
middle
of
their
transaction
execution,
and
so
this
is
actually
a
tremendous
change.
But,
however,
it's
not
really
secure
today
because
of
the
way
that,
like
bundles
and
like
transactions,
can
be
reordered
out
of
the
search
result
that
you
find.
So
you
imagine
you
like
search
for
this
amazing
interaction
with
the
smart
contracts.
Sorry
with
the
smart
transactions.
Excuse
me
no
and
then,
and
then
someone
else
Jacks
it
and
changes
uses
different
input,
values
for
the
same
transactions
and
then
you
sort
of
get
wrecked
on
your
execution.
A
You
know
basically
like
the
search
is
not
secure.
That
means
that
these
Mev
time
interactions
are
not
secure,
but
if
they
can
be
secured
actually,
basically
anything
a
Searcher
knows
can
be
given
to
the
transaction
and
they
can
use
it.
They
can
become
aware
of
not
just
their
execution
on
this
Trace,
but
all
the
other
counter
factual
timelines.
They
have
many
possible
presence,
Futures
and
pasts,
because
that's
sort
of
like
what
transactions
are
like
before
they're
included
in
a
block
and
finally
actualize.
A
A
A
We
can
do
it
and
it's
going
to
happen
because,
like
the
the
competitive
pressure
is
too
great-
and
so
this
is
sort
of
this
argument-
I
like
to
say
underwrites,
my
prophecy
sort
of
signs
off
on
it
and
and
basically
it's
sort
of
you
have
to
take
it
for
granted,
or
you
have
to
believe
me
that
I
can
secure
the
search,
but
if
I
can
secure
the
search.
I
can
do
this
Mev
time.
A
Interaction
I
can
inform
the
transactions
of
anything
basically,
and
then
they
can
sort
of
do
this
crazy
stuff
of
like
lots
of
like
wild
magic
which
we'll
get
to
very
soon.
So
what
is
the
state
of
the
art
in
smart
transactions
today?
Well,
this
is
sort
of
the
state
of
the
art.
In
my
tech,
research,
the
economics
and
law
and,
like
other
research,
has
been
sort
of
there's
not
enough
time
for
for
all
of
it.
A
Unfortunately,
so
basically,
smart
transaction
infrastructure
is
basically
a
story
of
store
transactions
like
pulling
themselves
up
by
the
bootstraps,
using
a
little
bit
of
awareness
to
get
a
little
more
awareness
to
try
to
get
sort
of.
You
know
very
secure
basis.
A
lot
of
awareness
for
the
transactions
and
so
I
split
it
up
into
phases
that
are
designed
to
be
sort
of
acceptable
to
our
current
normal
trust
model
at
first
and
then
deviate
a
little
bit
only
as
necessary
and
then
come
back
so
that,
like
it's,
a
minimally
politically
objective
objectionable
for
everyone.
A
So
basically
in
phase
one,
we
save
gas
in
this
very
classic
way
of
like
not
doing
those
pesky
out
of
gas
transactions,
save
one
and
phase
one
sorry,
we
we
have
semi-automacy,
which
means
like
you,
can
execute
the
prefix
of
a
bundle.
You
can't
choose
the
suffix
or
like
anything
that
isn't
a
prefix.
So
it's
like
not
a
Missy,
but
you
least
you
sort
of
I
can
restrict
using
the
evm's
rules.
Only
sort
of
that
you
can
only
do
a
prefix
I'm.
A
Phase
two
is
the
interesting
one
that
deviates
from
like
the
current
trust
model
that
people
have,
which
is
basically
I'm
saying
like.
Oh,
you
know,
we
actually
need
to
like
essential
it's
essential
that
we
trust
the
proposal
for
a
moment
just
for
a
moment
just
for
like
this
phase
two,
we
trust
the
proposer
and
then
in
phase
three
we
removed
the
trust
from
the
proposal
by
sort
of
locking
down
their
commitments,
making
it
making
them
like
unable
to
screw
us.
A
So,
basically,
in
phase
two,
we
sort
of
normally
are
very
uncomfortable
with
because,
like
the
whole
movie,
space
has
been
set
up
to
defend
you
against
the
search
and
I
guess
the
proposer,
but
I
insist:
it's
necessary.
There's
no
way
to
do
bundle
protection
without
this.
If
you
try
to
do
it
without
the
proposal,
you
won't
be
able
to
do
it.
The
proposal
is
so
important.
He's
either
they're
the
they're,
the
signature
on
the
Block.
They
make
it
a
block.
You
can't
make
a
block
without
the
stake.
A
A
Basically,
the
today
we
sort
of
had
this
idea.
We
don't
trust
the
proposal,
but
we
really
got
it.
We
really
got
to
in
order
to
get
out
of
my
City
full
of
atomicity,
and
then
we
can
lock
it
down,
not
trust
them
anymore
in
the
next
phase
and
then
after
we
have
the
the
atomicity
of
these
of
these
search
results.
A
They're,
just
they're
extracting
value
from
you
from
their
perspective
review
for
any
perspective,
you're
sort
of
hijacking
that,
in
the
way
that
like,
for
example,
like
fruit,
hijack
fruit
eating
animals
in
order
to
spread
their
seed
as
an
example,
so
here's
some
more
Tech
City
art
stuff.
So
this
is
an
example
of
formal
semantics
of
what
I
call
Smart
transitions.
So
smart
transitions
is
sort
of
like
a
idea
that
comes
from
Smart
transactions,
it
sort
of
generalizes
it
to
like
all
sorts
of
different
computer
science.
A
A
In
order
to
see
in
the
future
whether
the
thing
that
happened
was
supposed
to
happen
and
then
validate
basically
the
current
transition
based
on
like
what
happens,
many
transitions
down
in
the
future
sort
of
violating
normal
transition
semantics
in
a
very,
very
interesting
way,
which
I
call
Smart
and
basically
the
the
idea,
is
like
they
can
sort
of
look
into
the
future,
but
in
general
you
know
far
and
wide
all
over
the
place.
So
basically
here's
like
the
transitions,
so,
let's
just
like
go
through
them
quickly.
A
A
What
it'll
do
is
it'll
apply
the
transition
with
this
label
L
and
this
message
m
to
the
second
state,
so
the
original
state
is
left
untouched
and
the
second
state
is
updated
to
the
new
state
and
then
it
outputs
like
a
message
in
this
like
little
temporary
buffer
zone
from
that
transition,
and
so
like
it
collects
these
messages
and
updates
the
state.
While
it's
speculating
and
then
you
can
do
a
validate
transition,
which
will
either
do
one
or
two
things,
one
of
them
is
it'll.
A
It'll
delete
the
speculative
execution
state
or
it'll
delete
the
current
like
current
state
like
the
old
State,
and
so
the
one
you
just
validate
stuff.
It's
like
a
few
transitions
later,
at
least
one
transition
later
and
then
based
on
the
validity
of
that
transition,
you
sort
of
either
revert
all
the
previous
transitions
or
you
sort
of
choose
them.
You
sort
of
collapse,
this
superposition
of
like
the
old
State
and
the
new
state.
A
You
just
get
the
new
state,
so
this
sort
of
is
a
speculative
execution
transition
system
based
on
like
a
one
transition,
and
basically
the
amazing
thing
about
this-
is
that
you
can
sort
of
implement
ethereum
out
of
gas
semantics
sort
of
like
just
with
this.
Basically,
you
charge
an
account
gas.
You
do
a
bunch
of
execution
speculatively
thinking,
they
won't
run
out
of
gas
if
they
run
out
of
gas,
you
throw
out
all
those
changes
you
go
back
to
that
just
after
the
charge.
A
State
and
sort
of
you
can
use
this
as
like
justify
actually
that
ethereum
transactions
are
already
sort
of
smart
just
with
respect
to
the
out
of
gas
exception.
That
is
that
the
block
is
aware
of
on
the
sort
of
block
limit
transaction
limit
sort
of
level.
I
mean
the
block,
I
mean
it
might
be
the
validator
or
something
you
know,
and
so
basically,
but
this
idea
of
like
validating,
based
on
what
happens
in
the
future
sort
of
it
could
be
done
much
much
more
widely
than
just
out
of
gas.
A
You
can
just
sort
of
refine
those
validity
checks
to
add
whatever
constraints
you
want,
you
know
you
could
you
could
have
you
know
more
than
this
amount
of
men
of
like
better
than
this
performance,
as
you
revert
Etc
and
the
nice
thing
about.
This
is
sort
of
okay.
That
was
one
specular
execution,
but
we
do
the
same
thing
where
we
do
many
many
many
specular
executions
where
and
then.
A
But
that's
just
looking
forward.
I
mean
like,
and
this
stuff
really
can
look
back
and
a
different
alternative
presence,
either
also,
which
is
sort
of
it's
sort
of
a
trip
and
sort
of
really
really
helped
me
get
intuition
for
quantum
mechanics,
randomly
anyways,
so
use
cases,
challenges
and
implications.
There's
there's
stuff
from
the
slides,
I
haven't,
read
I'm
trying
to
really
rush
through
this,
but
some
of
it's
going
to
come
back
up
now,
I
realize
so.
Basically
there's
a
bunch
of
stuff.
A
I'm
trying
to
say
this
is
this
is
like
totally
dominant
Paradigm
or
basically
like
no
matter
what
you
think
of
you
can
do
more
efficiently
with
smart
transactions,
except
for
maybe
a
simple,
send
Maybe
Jerry's
out,
it's
probably
more
efficient
with
smart
transactions
anyways,
but
it's
gonna
be
more
like
a
smart
trans,
smart
operation
or
something
like
that.
So
basically
long
story,
short
or
I
mean
here's
a
bunch
of
here's.
What
it
says.
A
A
We
can
save
gas
and
pay
without
you.
This
is
sort
of
like
classic
stuff
for
Mev,
but
the
way
that
it's
done
in
smart
transactions
is
a
little
more
Capital
efficient,
maybe
a
lot
more
Capital
efficient
in
some
cases
rent
as
expected,
Mev
to
justify
stated
Ram.
This
is
sort
of
interesting
thing.
We
have
like
a
long
problem
in
ethereum
about
State
rented
statelessness
and
how
will
people
have
the
state?
Why
will
they
know
to
how
will
they
validate
my
transaction
like
now
like?
How
will
they
search
it,
and
the
answer
is
like?
A
Oh,
if
you
have
enough,
if
they
expect
enough
amount
of
they
they'll
store
it
and
they'll
speculate
on
that
in
all
sorts
of
ways.
Maybe
they'll
even
do
it
in
a
way,
that's
sort
of
like
public
value
as
opposed
to
internalized
value,
and
so
basically,
rent
actually
comes
in
through
the
back
door,
not
through
smart
transactions
but
like
Mev
in
general,
but
I
think
smart
transactions
in
particular,
because
sort
of
they
can
be
metal.
A
They
can
be
rent
aware
in
a
way
that's
sort
of
like
a
function
of
what
is
happening
on
the
searcher's
realm
and
what
the
serger's
policy
is
for
what
they
choose
to
put
in
their
Ram,
and
so
it
could
be
like
sort
of
very
specific
and
very
flexible
compared
to
like
all
the
men,
all
the
red
proposals.
So
far,
automated
collective
bargaining,
pretty
cool
right.
A
A
Direct
economic
interventions
at
all
scales
is
very,
very
cool.
You
can
basically
use
macro
statistics,
micro
statistics,
mental
statistics
and,
like
just
pay
for
those
outcomes
in
a
sort
of
very
direct
way.
That's
sort
of
lacking
today
in
like
public
policy
or
basically
like
helicopter
Ben,
has
a
really
hard
time
dropping
money
on
people,
but,
like
sort
of
we
see
all
the
transactions
on
all
the
timelines
like
collapse
into
one
and
sort
of
like
can
pay
the
Searchers
to
for
whatever
policy
goal.
A
We
want
it's
amazing
just
in
time
liquidity
pools,
it's
pretty
cool.
Imagine
the
liquidity
follows
the
different
trades
within
your
transaction
around
just
to
serve.
You
better
amazing
can't
happen
today
because
of
the
transaction
timing
and
the
operation
timing
doesn't
allow
for
it:
zero
Capital,
zero
credit
trading.
A
At
the
start
of
the
block
and
sort
of
have
it
all
work
out,
amazing
amazing,
you
can
hedge
quote
unquote,
using
exactly
the
cost
that
are
incurred
at
the
end
of
the
block.
It's
not
even
really
hedging,
because
you
know
for
sure
the
cost
it's
like
the
most
efficient.
It
could
possibly
be
for
certain
instruments
and
lots
of
other
stuff,
but
we
have
challenges
still.
A
Unfortunately,
unfortunately,
this
can
be
very,
very
computationally,
expensive,
simultaneously
searching
for
all
these
Solutions
at
the
same
time
for
all
these
transactions,
especially
if
everyone's
demanding
them,
you
know,
there's
a
lot
of
them.
It
can
be
very
hard
who
knows
how
the
complexity
grows
in
the
search
transactions.
It
depends
on
what
they're
doing
I
could
definitely
design
smart
transactions
that
do
really
bad
for
the
Searchers
and
they
basically
don't
have
Solutions
the
more
you
add
to
them.
A
Like
you
know,
they
might
have
a
solution
subtractively
for
a
few,
but
then,
like
the
big
goes
so
bad,
like
you,
add,
10
more
and
then
just
you
can't
solve
them
anymore,
and
this
is
why
this
dos
and
gas
Insurance
Market
is
so
important
because,
like
you
kind
of
need,
they
need
to
figure
out
like.
Is
this
a
Dos
attack?
Is
this
a
legitimate,
smart
transaction?
A
Is
it
something
that
is
going
to
have
a
solution,
or
is
it
something
that's
we're
wasting
our
search
on
in
order
because
it
just
computationally
very
difficult
to
find
all
these
Solutions
also,
you
know,
I
mentioned
all
these
kind
of
counterfactual
stats
and
claims
and
things
sir.
The
Searcher
knows
that
but
like.
Why
should
your
transaction
trust
the
Searcher,
to
give
it
the
right
values
like
there
are
sort
of
like
challenge
challenges
with
respect
to
verifying
these
these
inputs
especially
efficiently
and
then
there's
a
multi-block
issue
which
is
like?
A
Actually
we
wouldn't.
We
don't
want
in
some
way,
transactions
should
like
end
in
one
block,
to
finish
to
just
finish,
validating
everything
in
one
block.
It's
a
very
nice
to
have
multi-block
transactions
and
to
do
this
efficiently
is
a
challenge,
especially
composed
with
all
the
other
search,
so
rather
than
all
the
searches
being
sort
of
like
this
block.
A
As
sort
of
you
know,
this
Mev
space,
where,
basically
you
know
you're
responding
to
this
meta
search
because,
actually,
like
the
smart
transaction
validation,
is
sort
of
very
wide,
it
doesn't
need
to
be
validating
anything
to
do
with
map
and
this
sort
of
useful
industry.
The
systems
in
a
broad
way
is
in
transactional
systems
in
our
very
broad
way,
and
especially
smart
transactions
are
sort
of
not
just
Mev.
Nev
is
sort
of
you
know
like
an
economic
thing,
it's
like
only
one
side
of
the
story.
A
They
also
have
really
amazing
computer
science
Innovations,
not
that
the
economic
stuff
isn't
great
I
mean
the
risk
management.
Customer
transactions
do
like
that.
Hedging.
That
I
was
talking
about
earlier.
Amazing,
basically
can
really
really
make
things
much
more
economically
efficient
and
then
sort
of
like
legally.
A
This
is
my
concluding
slide
and
they're
missing
a
will
there,
oh
no,
they
do
they
do
actually
revolutionize
now
ethereum
is
transactional,
semantics
and
sort
of
like
that's.
Like
sort
of
you
know
the
prophecy
and
like
sort
of
like
the
fact
in
the
future,
which
is
sort
of
like
I,
guess
what
a
prophecy
should
do.
Thank
you
so
much.
Everyone
really
appreciate
it.
I
have
more
I
have
more
come.
Come
see
me
later.