making some progress...

core/Cargo.toml

@@ -15,21 +15,21 @@ description = "Sign extrinsics to be submitted by Subxt"
 keywords = ["parity", "subxt", "extrinsic", "no-std"]
 
 [features]
-default = ["std"]
+# default = ["std"]
 std = []
 substrate-compat = ["sp-core", "sp-runtime"]
 
 [dependencies]
 
 codec = { package = "parity-scale-codec", workspace = true, features = ["derive"] }
-scale-info = { workspace = true }
-scale-value = { workspace = true }
-scale-bits = { workspace = true }
-scale-decode = { workspace = true }
-scale-encode = { workspace = true }
+scale-info = { workspace = true, default-features = false, features = ["bitvec"] }
+scale-value = { workspace = true, default-features = false }
+scale-bits = { workspace = true, default-features = false }
+scale-decode = { workspace = true, default-features = false }
+scale-encode = { workspace = true, default-features = false }
 frame-metadata = { workspace = true }
 subxt-metadata = { workspace = true }
-derivative = { workspace = true }
+derivative = { workspace = true, features = ["use_core"] }
 derive_more = { workspace = true }
 hex = { workspace = true }
 serde = { workspace = true, features = ["derive"] }
@@ -41,7 +41,7 @@ blake2 = { workspace = true }
 
 # Provides some deserialization, types like U256/H256 and hashing impls like twox/blake256:
 impl-serde = { workspace = true }
-primitive-types = { workspace = true }
+primitive-types = { workspace = true, default-features = false, features = ["codec", "serde_no_std", "scale-info"] }
 sp-core-hashing = { workspace = true }
 
 # For parsing urls to disallow insecure schemes
@@ -50,6 +50,7 @@ url = { workspace = true }
 # Included if the "substrate-compat" feature is enabled.
 sp-core = { workspace = true, optional = true }
 sp-runtime = { workspace = true, optional = true }
+cfg-if = "1.0.0"
 
 
 [dev-dependencies]