diff --git a/README.md b/README.md
index e1f52c1..f045495 100644
--- a/README.md
+++ b/README.md
@@ -592,15 +592,17 @@ Phase 1: scaffolding
 
 Phase 2: crypto primitives
 
-- [ ] Wrap libsodium init as an awaitable singleton
-- [ ] `deriveKEK(password, kekSalt, memLimit, opsLimit)` (Argon2id)
-- [ ] `deriveLoginSubkey(kek)` (KDF with subkey id 1, context `loginctx`, 16
+- [x] Wrap libsodium init as an awaitable singleton
+- [x] `deriveKEK(password, kekSalt, memLimit, opsLimit)` (Argon2id)
+- [x] `deriveLoginSubkey(kek)` (KDF with subkey id 1, context `loginctx`, 16
       bytes)
-- [ ] `decryptBox(ciphertext, nonce, key)` for secretbox
-- [ ] `decryptSealed(ciphertext, publicKey, secretKey)` for sealed box
-- [ ] `initStreamPull` and `pullStreamChunk` for chunked secretstream (4 MiB
+- [x] `decryptBox(ciphertext, nonce, key)` for secretbox
+- [x] `decryptSealed(ciphertext, publicKey, secretKey)` for sealed box
+- [x] `initStreamPull` and `pullStreamChunk` for chunked secretstream (4 MiB
       plaintext chunks, 17-byte overhead)
-- [ ] Round-trip tests against vectors generated by libsodium directly
+- [x] Round-trip tests against vectors generated by libsodium directly
+- [x] Base64 helpers (`fromBase64`, `toBase64`, `toBase64URL`) accepting all
+      four sodium variants on input
 
 Phase 3: SRP + auth