2 files changed, 24 insertions, 3 deletions
diff --git a/crates/tor-hscrypto/Cargo.toml b/crates/tor-hscrypto/Cargo.toml
index d6f879092..bc84a9d07 100644
--- a/crates/tor-hscrypto/Cargo.toml
+++ b/crates/tor-hscrypto/Cargo.toml
@@ -17,8 +17,8 @@ memquota-memcost = ["derive-deftly", "tor-memquota", "tor-units/memquota-memcost
 ope = ["cipher", "zeroize"]
 
 # Onion service proof of work schemes
-pow-v1 = ["arrayvec", "blake2", "equix"]
-pow-full = ["pow-v1"]
+pow-v1 = ["arrayvec", "blake2", "equix", "__is_experimental"]
+pow-full = ["pow-v1", "__is_experimental"]
 
 full = [
     "memquota-memcost",
@@ -29,8 +29,16 @@ full = [
     "tor-llcrypto/full",
     "tor-units/full",
     "tor-error/full",
+    "equix?/full",
+    "tor-memquota?/full",
 ]
 
+experimental = [
+    "pow-full",
+    "pow-v1",
+]
+__is_experimental = []
+
 [dependencies]
 arrayvec = { version = "0.7.4", optional = true }
 blake2 = { version = "0.10.6", optional = true }
diff --git a/crates/tor-hscrypto/README.md b/crates/tor-hscrypto/README.md
index 3a8036be8..91b563a41 100644
--- a/crates/tor-hscrypto/README.md
+++ b/crates/tor-hscrypto/README.md
@@ -32,12 +32,25 @@ onion services.
 
 * `ope` -- support for Order Preserving Encryption
 
+* `full` -- Enable all features above.
+
+### Experimental and unstable features
+
+Note that the APIs enabled by these features are NOT covered by
+semantic versioning[^1] guarantees: we might break them or remove
+them between patch versions.
+
 * `pow-v1` -- Tor Hidden Services Proof of Work (`v1` scheme only)
 
 * `pow-full` -- Tor Hidden Services Proof of Work
   (metafeature, enables all non-experimental schemes: currently, implies only `pow-v1`).
 
-* `full` -- Enable all features above.
+* `experimental`: Enable all the above experimental features.
+
+[^1]: Remember, semantic versioning is what makes various `cargo`
+features work reliably. To be explicit: if you want `cargo update`
+to _only_ make safe changes, then you cannot enable these
+features.
 
 ## License