Willem Schroé: Building Botanix, a Bitcoin Layer 2 That Brings the EVM to Bitcoin

When
Willem
Schroé
was
17,
he
came
in
third
out
of
10,000
in
a
national
math
competition
in
Belgium,
his
home
country.
His
prize
was
a
book
on
botanics,
the
study
of
mathematics
and
fractals
in
nature.
The
book
inspired
awe
in
him,
as
he
was
humbled
by
the
notion
that
physics
and
mathematics
are
bigger
than
any
one
of
us.
Today,
he
feels
the
same
way
about
Bitcoin,
which
is
why
he’s
building
a
groundbreaking
Layer
2
on
the
network.
But,
before
we
get
to
that,
let
me
offer
you
some
background
on
Schroé.

Frank
Corva


is
the
Business-to-Business
Correspondent
at
Bitcoin
Magazine
and
host
of
the
new
renaissance
capital
podcast.

Schroé
completed
a
bachelor’s
and
master’s
degree
in
engineering
at
KU
Leuven,

the
best
university
in
Belgium
and

one
of
the
best
universities
in
the
world.
For
his
graduate
degree,
he
focused
on
cryptography
with
a
specialization
in
authenticated
encryption
and
forward
secrecy.
He
pursued
his
studies
in
the
school’s
world-renowned
Computer
Security
and
Industrial
Security
(COSIC)
program,
where
legendary
cryptographers

David
Chaum
and

Len
Sassaman
once
lectured.

Schroé’s
thesis
advisor
was
Vincent
Rijmen,
inventor
of
the
Advanced
Encryption
Standard
(AES),
which
the
U.S.
government
uses
to
protect
classified
data.

After
graduating,
Schroé
couldn’t
find
a
tech
gig
in
Belgium,
so
he
went
into
chemical
engineering.
He
landed
a
job
at
a
joint
venture
between
ExxonMobil
and

SABIC
in
Saudi
Arabia.
On
a
business
trip
to
Lebanon
in
2019,
he
saw
the
ravaging
effects
of
hyperinflation
on
the
country.
Deeply
impacted
by
the
experience,
he
decided
to
focus
on
building
a
better
financial
system
on
Bitcoin.

“I
committed
myself
to
spending
all
my
resources,
all
my
capabilities
to
make
sure
I
helped
Bitcoin
succeed
as
soon
as
possible,
because
I
could
really
see
the
world
was
moving
faster
and
faster
into
a
darker
place,”
says
Schroé.
“I
see
Bitcoin
as
being
the
light.”

Soon
after,
he
applied
and
was
accepted
to
Harvard
Business
School.
While
at
Harvard,
he
continued
to
think
about
how
to
move
Bitcoin
forward
but
also
took
notice
of
the
popularity
of
NFTs
and
the
amount
of
trading
volume
on
decentralized
exchanges
(DEX).
He
still
believed
in
bitcoin
as
sound
money
but
could
not
ignore
the
other
technologies
in
the
crypto
space
that
were
achieving
product-market
fit.
This
is
when
he
conceptualized
Botanix,
a
Bitcoin
Layer
2
that
employs
bitcoin
as
money
on
the
Ethereum
Virtual
Machine
(EVM)
via
a
novel
design
structure
that
Schroé
calls
“the
spiderchain.”
The
name
Botanix
was
inspired
by
the
subject
of
the
book
he
won
at
age
17
—
a
nod
to
the
idea
that
Bitcoin,
which
is
governed
by
mathematics,
is
bigger
than
all
of
us.

Fast-forward
to
late-2023
and
the

Botanix
testnet
is
live.

I
spoke
with
Schroé
virtually
while
he
was
attending

ETHDenver,
in
March,
to
learn
about
how
he
thinks
Botanix
will
be
received
by
both
the
Bitcoin
and
Ethereum
communities,
why
proof-of-stake
is
a
secure
consensus
mechanism
for
a
Bitcoin
Layer
2
and
what
challenges
he’s
faced
in
deploying
the
Botanix
testnet.

Interview
has
been
condensed
and
lightly
edited
for
clarity.

Please
tell
us
about
what
you’re
building
at
Botanix.
You’re
bringing
the
EVM
to
a
Bitcoin
Layer
2.
Why
do
you
think
people
want
to
use
their
bitcoin
on
the
EVM?

I
started
realizing
there’s
a
split
between
Ethereum
the
asset
and
Ethereum
the
virtual
machine.
I
strongly
believe
that
a
lot
of
the
value
that’s
being
created
on
Ethereum
is
actually
reflected
in
the
EVM.
When
I
think
about
the
future
running
on
Bitcoin
—
if
you
think
100
years
ahead
and
the
whole
world
runs
on
Bitcoin
—
you
need
to
have
stock
exchanges,
you
need
to
have
the
whole
financial
system
[on
Bitcoin].

Decentralized
exchanges
on
Ethereum
are
a
10x
version
of
stock
exchanges.
If
you
compare
Uniswap
to
the
New
York
Stock
Exchange,
Uniswap
is
way
more
efficient
and
open
24/7.
It’s
permissionless,
capable
of
being
accessed
by
anyone
in
the
world.
But
I
strongly
believe
that
bitcoin
is
the
best
money.
Like
Michael
Saylor
would
say,
there
is
no
second
best.
So,
it
makes
the
most
sense
to
actually
build
[financial
services]
natively
on
Bitcoin.
That’s
what
we
want
to
do,
and
I
think
it
will
play
out
very
fast,
because
you
can
copy-paste
any
smart
contract
on
Ethereum
today
and
deploy
it
on
Botanix.

When
you
start
seeing
that
happen
—
when
you
see
the
bitcoin
in
your
MetaMask
—
you
realize
that
the
EVM
is
just
a
software
layer.
To
answer
your
question:
“What
would
people
want
to
do
with
their
bitcoin?”
One,
since
all
the
gas
fees
and
transaction
fees
are
in
bitcoin
on
the
second
layer,
you
will
be
able
to
stake
bitcoin
and
actually
get
native
bitcoin
yield.
You
will
be
able
to
trade
bitcoin
against
other
tokens.
You
will
be
able
to
launch
a
bitcoin-backed
stablecoin
on
Bitcoin.

All
these
applications
have
reached
product-market
fit.
This
is
the
next
step
in
actually
building
a
whole
world
that
runs
on
Bitcoin.
It
also
immediately
scales
Bitcoin.
We
go
from
Bitcoin
on
the
base
layer
with
10
minute
blocks
—
very
slow,
fully
decentralized.
Botanix
is
a
little
bit
faster
—
10
second
blocks
like
Ethereum
and
as
decentralized
as
Ethereum.
Then
you
go
from
there.
You
have
the
Layer
2s
on
Ethereum
right
now
with
very
high
throughput,
like
0.2,
0.1
second
blocks.
You
can
have
that
as
Layer
3
on
Botanix.
It’s
copy-paste.

Suddenly,
you
can
see
a
future
where
you
can
scale
Bitcoin
to
eight
billion
people.
100
years
from
now
you’ll
have
DEXs
and
decentralized
lending
and
borrowing
protocols
[on
Bitcoin],
which
is
a
10x
better
version
of
the
financial
system
that
we
have
today.
Bitcoin
is
a
big
breakthrough
in
terms
of
money,
but
EVM
is
the
big
breakthrough
in
terms
of
financial
system.

You
used
the
phrase
“100
years
from
now.”
You’re
obviously
thinking
long-term
when
it
comes
to
Botanix.
Do
you
envision
tokenized
versions
of
all
real
world
assets
(RWA)
on
Bitcoin?

Absolutely.
That
is
the
vision.
I
think
we
are
going
through
the
same
cycle
we
saw
over
the
last
100
years.
When
you
go
back
100
years,
before
the
SEC
existed,
the
1910s
or
the
1920s,
there
were
no
rules
and
everybody
could
launch
stocks
for
their
own
company.
Today,
that’s
what
we
see
with
all
the
tokens.
There’s
no
regulation.
In
this
new
financial
system,
we
are
in
the
1910s
again.
What
I
see
a
hundred
years
from
now
is
bitcoin
being
the
money
and
having
a
full
financial
system
also
running
in
a
more
decentralized,
more
permissionless
version
than
we
have
today.
I
would
hate
it
if
we
ran
the
whole
world
on
Bitcoin
but
with
the
current
financial
system,
where
all
the
bitcoins
are
with
central
banks.
They
will
just
loan
them
out
again
and
create
new
fake
bitcoin.
I
do
not
want
that
future.

You’ve
said
that
the
EVM
isn’t
the
best
virtual
machine
technology
out
there.
If
you
feel
this
way,
why
use
it?

The
parallel
I
always
make
is
to
Microsoft
Windows
in
the
80s.
Any
software
technology
battle
follows
the
same
principles
and
rules.
Windows
in
the
80s
didn’t
win
because
it
was
the
best
or
most
secure
technology.
The
reason
it
gained
so
much
adoption
is
distribution.
Windows
was
by
far
the
best
in
distribution.

The
EVM
is
definitely
not
the
best,
definitely
not
the
most
secure.
There
have
been
so
many
hacks
on
the
EVM,
but
this
gave
rise
to
the
whole
audit
industry.
You
also
have
a
Lindy
effect
happening
on
the
EVM
[with
certain
dapps].
You
could
argue
“Okay,
we’ve
seen
a
few
smart
contracts
like
Uniswap
survive
for
so
long
without
any
smart
contract
hacks.”
They
could
be
considered
more
secure.
But
the
base
layer
of
the
EVM
is
definitely
not
the
most
secure.
It
just
has
the
biggest
distribution.

I
heard
both
yourself
and
some
other
more
technically-minded
people
in
the
space
say
that
proof-of-stake
works
for
a
second
layer
on
Bitcoin
but
not
as
a
base
layer.
Why
is
that?

That
is
a
very
good
question.
I
was
actually
a
proof-of-work
maximalist
before
designing
the
spiderchain,
but
I
realized
that
a
proof-of-work
on
a
second
layer
actually
doesn’t
make
a
lot
of
sense.
So,
I
looked
into
proof-of-stake
and
read
all
the
different
white
papers.
In
2022,
when
Ethereum
merged
to
proof-of-stake,
there
were
a
lot
of
Bitcoiners,
including
Jack
Dorsey,
who
were
retweeting
this

article
about
why
proof
of
stake
is
insecure.
So,
I
read
the
article.
Each
of
the
arguments
in
it
were
actually
solved
if
you
build
with
proof-of-stake
on
a
second
layer.
Let
me
go
quickly
over
the
arguments.
Number
one
is
the
economic
argument.
Proof-of-work
is
a
leaking
system
and
proof-of-stake
is
a
closed
system.
That
means
that
proof-of-work
has
a
decentralizing
trend.
You
need
to
pay
for
the
electricity,
so
value
leaks
out
of
the
system.
Bitcoin,
over
time,
becomes
more
and
more
decentralized,
because
that
value
leaks
out
into
the
real
world.
Proof-of-stake
is
the
opposite.
It
actually
has
a
centralizing
trend.
The
stakers
get
a
bigger
and
bigger
portion
of
the
total
100%
share
of
the
assets
over
time.
As
a
layer
one,
as
a
currency,
that
doesn’t
make
a
lot
of
sense.

With
a
second
layer
fully
running
on
bitcoin,
you
can
use
proof-of-stake,
which
has
a
small
centralizing
trend.
Let’s
say
that
10-30%
of
all
the
bitcoin
would
be
on
the
second
layer.
That
is
counteracted
by
the
100%
of
bitcoin
that
is
actually
decentralized.
So,
that’s
solved.
The
second
argument
is
finality.
The
problem
with
proof-of-stake
is
what
you
call
the
nothing-at-stake
attack.
Basically,
you
stake
some
bitcoin,
then
you
fork
the
chain
and
take
away
some
bitcoin
on
one
of
the
forked
chains.
So,
you
no
longer
have
anything
at
stake
and
you
can
do
a
double-spend.

So,
you’re
leveraging
all
of
these
important
dynamics
from
Bitcoin’s
proof-of-work
consensus
mechanism.
Now,
please
explain
to
us
how
the
spiderchain
works.

The
spiderchain
is
designed
to
be
inherently
decentralized.
When
we
started
to
design
it,
we
looked
at
all
Layer
2s
and
realized
that
all
of
them
are
basically
centralized.
All
the
Ethereum
sits
in
a
centralized
smart
contract.
We
designed
the
spiderchain
to
be
capable
of
being
as
decentralized
as
Ethereum.

We
saw
the
power
of
the
EVM
and
we
designed
Botanix
to
be
[compatible]
with
the
Bitcoin
Core,
capable
to
run
an
EVM
and
decentralized.
That
is
the
box
that
we
designed
in
to
come
up
with
the
spiderchain.
We
call
it
a
decentralized
network
of
multisigs.
We
designed
it
much
like
the
Lightning
Network.
The
Lightning
Network
is
actually
a
decentralized
network
of
two-out-of-two
multisigs.
Take
the
idea
of
the
Lightning
Network,
but
think
of
it
bigger.
If
you
have
10,000
different
people
all
running
a
full
Botanix
node,
you
will
create
a
series
of
multisigs.
You
randomly
choose
100
participants
out
of
the
10,000
and
they
will
secure
multisig
one.
Then
you
do
that
again
for
multisig
two
and
randomly
choose
100
participants
out
of
the
10,000
different
nodes,
and
they
will
secure
multisig
two.
You
do
that
again
for
multisig
three,
and
four,
and
five,
and,
after
a
while,
you
create
a
series
of
multisigs
that
create
this
whole
overlay
network
on
Bitcoin
that
anyone
can
participate
in.

This
network
of
decentralized
multisigs
is
the
spiderchain.
Then
you
use
that
with
a
proof-of-stake
consensus.
If
you
try
to
steal
any
bitcoin,
you’ll
get
slashed.
Proof-of-stake
both
secures
the
decentralized
network,
where
the
bitcoin
actually
sits
in
the
multisigs,
and
the
EVM.

You’ve
said
that
you
expect
to
get
a
lot
of
heat
from
both
Bitcoin
and
Ethereum
maxis
for
what
you’re
building.
What
has
been
the
reaction
from
the
Ethereum
crowd?

On
the
ETH
side
of
things,
you
have
two
typical
people.
You
have
the
OG
Bitcoiners,
the
people
who
started
in
Bitcoin,
couldn’t
build
on
it
and
moved
away
from
it.
They
went
to
Ethereum,
but
somewhere
in
their
hearts,
they
still
loved
Bitcoin.
There’s
a
lot
of
people
like
that.
A
lot
of
the
founders
of
Ethereum
apps
are
OG
Bitcoiners
—
even
Vitalik
[Buterin],
right?
Then
you
have
the
Ethereum
maxis
that
probably
entered
the
space
during
2021-2022,
and
they
just
consider
bitcoin
a
store
of
value.
They
don’t
understand
why
you
would
want
to
build
on
Bitcoin.

Do
you
find
that
there
are
plenty
of
people
out
there
who
like
Bitcoin
and
Ethereum?
Are
people
not
as
tribal
as
they
appear
to
be
on
X
(formerly
Twitter)?

There’s
way
more
than
people
realize.
When
you
look
at
Twitter,
you
hear
the
loudest
voices,
the
most
extreme
voices.
But
I
would
say
the
majority
of
Ethereum
enthusiasts
have
some
bitcoin
in
their
cold
wallet.
The
fact
is
you
cannot
do
anything
with
[bitcoin].
[In
a
follow-up
interview,
Schroé
clarified
that
he
meant
to
say
you
cannot
do
many
things
with
bitcoin
on-chain.
He
also
shared
that
he’s
well
aware
that
just
holding
bitcoin
as
a
hedge
against
currency
debasement
or
using
it
for
transactions
in
the
real
world
has
great
value.]

There’s
no
infrastructure
to
do
something
with
it.
You
can
go
on
Lightning
and
send
a
transaction,
but
that’s
about
it.
Botanix
suddenly
changes
that.
A
big
reason
why
Ordinals,
NFTs
and
BRC-20s
blew
up
is
because
suddenly
you
could
do
something
with
bitcoin.
There’s
this
huge
amount
of
demand
that
is
just
waiting
for
applications.
I’m
seeing
it
coming
from
people
who
are
ideologically
more
on
the
Bitcoin
side

and
people
who
are
more
ideologically
on
the
Ethereum
side.

I
wish
you
the
best
of
luck
in
bringing
the
mainnet
live.
Do
you
have
any
final
thoughts
you’d
like
to
share?

Try
out
the
testnet.
Once
you
see
Bitcoin
in
your
MetaMask,
it’s
a
game-changer.
If
you’ve
always
wanted
to
build
something
on
Bitcoin
but
couldn’t
and
you’ve
been
building
on
Ethereum,
definitely
think
about
building
on
Botanix.
If
you
are
an
Ethereum
developer,
and
you’ve
developed
a
smart
contract,
you
have
to
ask
yourself
the
question:
“Where
do
I
deploy?
Do
I
deploy
on
Ethereum
in
a
crowded
market
where
you
fight
for
TVL
and
users?
Or
I
deploy
on
Botanix
with
a
trillion
dollars
of
TVL
(referring
to
bitcoin
on
the
base
chain)?”
It
makes
way
more
sense
to
deploy
it
on
Botanix.
Over
the
next
two
or
three
years,
you’ll
see
that
play
out.
Over
10
years,
you’ll
100%
see
that
play
out,
because
bitcoin
will
always
be
the
biggest
capital
pool
[of
any
crypto
asset].