# Subsystem stability

This page documents the current stability of the various GNUnet subsystems. Stability here describes the expected degree of compatibility with future versions of GNUnet.

For each subsystem we distinguish between compatibility on the P2P network level (communication protocol between peers), the IPC level (communication between the service and the service library) and the API level (stability of the API).

P2P compatibility is relevant in terms of which applications are likely going to be able to communicate with future versions of the network. IPC communication is relevant for the implementation of language bindings that re-implement the IPC messages. Finally, API compatibility is relevant to developers that hope to be able to avoid changes to applications built on top of the APIs of the framework.

The following table summarizes our current view of the stability of the respective protocols or APIs:

Todo

Make table automatically generated individual pages?

Subsystem | P2P | IPC | C API
--- | --- | --- | ---
util | n/a | n/a | stable
arm | n/a | stable | stable
block | n/a | n/a | stable
cadet | testing | testing | testing
consensus | experimental | experimental | experimental
core | unstable | unstable | unstable
datacache | n/a | n/a | unstable
datastore | n/a | unstable | unstable
dht | testing | testing | testing
dns | stable | stable | stable
dv | testing | testing | n/a
exit | testing | n/a | n/a
fragmentation | stable | n/a | stable
fs | unstable | unstable | unstable
gns | stable | stable | stable
hello | n/a | n/a | testing
hostlist | unstable | unstable | n/a
identity | testing | testing | n/a
multicast | experimental | experimental | experimental
namestore | n/a | testing | testing
nat | n/a | n/a | unstable
nse | stable | stable | stable
pt | n/a | n/a | n/a
regex | stable | stable | stable
revocation | stable | stable | stable
social | experimental | experimental | experimental
statistics | n/a | stable | stable
testbed | n/a | testing | testing
testing | n/a | n/a | testing
topology | n/a | n/a | n/a
transport | experimental | experimental | experimental
tun | n/a | n/a | stable
vpn | testing | n/a | n/a

Here is a rough explanation of the values:

Todo

0.10.x is outdated - rewrite "`stable`" to reflect a time-independent meaning.

'`stable`'

  No incompatible changes are planned at this time; for IPC/APIs, if there are incompatible changes, they will be minor and might only require minimal changes to existing code; for P2P, changes will be avoided if at all possible for the current major version.

'`testing`'

  No incompatible changes are planned at this time, but the code is still known to be in flux; so while we have no concrete plans, our expectation is that there will still be minor modifications; for P2P, changes will likely be extensions that should not break existing code

'`unstable`'

  Changes are planned and will happen; however, they will not be totally radical and the result should still resemble what is there now; nevertheless, anticipated changes will break protocol/API compatibility

'`experimental`'

  Changes are planned and the result may look nothing like what the API/protocol looks like today

'`unknown`'

  Someone should think about where this subsystem headed

'`n/a`'

  This subsystem does not implement a corresponding API/protocol