A 5 min discussion about how to improve API design by focusing on domain modeling (to identify entities, relationships, transitions, and events) and systems design (to find the context boundaries for our APIs).

1. API
Thinking
James
Higginbotham
API
Architect
@launchany

2. “I
say
this
constantly:
‘your
API
design
should
become
the
defini:on
of
your
new
target
architecture’
“
-­‐
@jharmn

3. I
ask:
“What
are
your
resources?”

4. Their
answer:
“How
do
I
figure
out
what
resources
I
need?”

5. “We
have
a
monolithic
app,
but
we
are
in
the
process
of
redesigning
it.”

6. Microservice
everything!
Containerize
it
all!

7. Maybe.
Maybe
not.

8. First,
we
need
to
be
able
to
look
at
our
soPware
systems
in
a
“fresh,
old
way”

9. Domain
Modeling
to
find
business
en::es,
rela:ons,
state
transi:ons,
and
events
(Domain-­‐Driven
Design)

10. Systems:
Solu:on
to
Problem(s)
Subsystems:
Bounded
Concerns
Modules:
Atoms
for
Composi:on

11. Automo:ve
Systems
u Engine
– Intake
– Exhaust
– Fuel
System
– Valve
Train
u Drive
Train
u Braking
System
u …

12. Third-­‐party
APIs
may
replace
modules,
subsystems,
or
even
en:re
systems

13. Once
we
understand
our
logical
architecture,
we
can
determine
the
op:on(s)
to
realize
it.

14. Our
API
resources
and
product
boundaries
become
more
apparent
as
well,
including
where
client
responsibility
starts
and
stops.

15. Systems
=
Solu:ons
Subsystems
=
Resources/Groups
Modules
=
Endpoints

16. What
might
this
look
like?

17. Subsystems:
Account
Management,
Inventory
Management,
Customer
Management,
Ecommerce,
Billing,
Analy:cs/Repor:ng

18. Each
subsystem
has
an
API
that
exposes
one
or
more
endpoints.

19. We
can
then
select
the
right
architectural
styles
we
need
to
realize
our
subsystems…

20. -­‐
Client/Server
-­‐
Service-­‐oriented
-­‐
Message-­‐oriented
-­‐
Event-­‐driven
-­‐
Pipe
and
Filter
-­‐
Yes,
even
microservices

21. “If
the
ranks
of
programmers
has
doubled
every
five
years,
then
it
stands
to
reason
that
most
programmers
were
hired
within
the
last
five
years”
–
Robert
C.
Mar:n
hDp://blog.cleancoder.com/uncle-­‐bob/2014/06/20/MyLawn.html

22. I’m
on
a
mission
to
help
teams
re-­‐think
the
way
they
architect
their
soPware,
resul:ng
in
be`er
API
designs
and
products.

23. James
Higginbotham
james@launchany.com
hDp://launchany.com
@launchany