chore: version bumps and note about versioning

README.md

@@ -42,6 +42,24 @@ recommend a specific security model. Any SPV verification involves complex
 security assumptions. Please seek external review for your design before
 building with these libraries.
 
+### A note about versioning
+
+Implementations are versioned separately. I.e. there is no consistent feature
+set for a given version number. Wherever possible we use SemVer. Because go's
+versioning system is ridiculous, all releases are minor bumps, even when they
+should be major bumps.
+
+This may change in future releases.
+
+At time of writing the following versions are roughly equivalent:
+- Go v1.4.0
+- JS v4.0.0
+- rust v3.0.0
+- py v3.0.0
+
+Versions older than these have incompatible JSON Proof and Header formats.
+
+
 ### Bitcoin Endianness Gotchas
 Block explorers tend to show txids and merkle roots in big-endian (BE) format.
 Most human-facing apps do this as well. However, due to Satoshi's inscrutable

js/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@summa-tx/bitcoin-spv-js",
-  "version": "3.0.0",
+  "version": "4.0.0",
   "description": "bitcoin SPV proofs in Javascript",
   "main": "dist/index.js",
   "engines": {

python/setup.py

@@ -7,7 +7,7 @@
 
 setup(
     name='bitcoin-spv-py',
-    version='2.0.0',
+    version='3.0.0',
     url='https://github.com/summa-tx/bitcoin-spv',
     author='James Prestwich',
     author_email='[email protected]',

rust/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "bitcoin-spv"
-version = "2.0.0"
+version = "3.0.0"
 authors = ["James Prestwich <[email protected]>"]
 edition = "2018"
 license="LGPL-3.0-or-later"