diff --git a/Cargo.lock b/Cargo.lock
index be7f917..677a62b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -17,6 +17,17 @@ version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
 
+[[package]]
+name = "ahash"
+version = "0.7.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "891477e0c6a8957309ee5c45a6368af3ae14bb510732d2684ffa19af310920f9"
+dependencies = [
+ "getrandom",
+ "once_cell",
+ "version_check",
+]
+
 [[package]]
 name = "aho-corasick"
 version = "1.1.3"
@@ -151,6 +162,27 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "597bb81c80a54b6a4381b23faba8d7774b144c94cbd1d6fe3f1329bd776554ab"
 
+[[package]]
+name = "bindgen"
+version = "0.65.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfdf7b466f9a4903edc73f95d6d2bcd5baf8ae620638762244d3f60143643cc5"
+dependencies = [
+ "bitflags 1.3.2",
+ "cexpr",
+ "clang-sys",
+ "lazy_static",
+ "lazycell",
+ "peeking_take_while",
+ "prettyplease",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "rustc-hash",
+ "shlex",
+ "syn 2.0.60",
+]
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -163,6 +195,18 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cf4b9d6a944f767f8e5e0db018570623c85f3d925ac718db4e06d0187adb21c1"
 
+[[package]]
+name = "bitvec"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bc2832c24239b0141d5674bb9174f9d68a8b5b3f2753311927c172ca46f7e9c"
+dependencies = [
+ "funty",
+ "radium",
+ "tap",
+ "wyz",
+]
+
 [[package]]
 name = "buffer-redux"
 version = "1.0.1"
@@ -178,6 +222,28 @@ version = "3.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "79296716171880943b8470b5f8d03aa55eb2e645a4874bdbb28adb49162e012c"
 
+[[package]]
+name = "bytecheck"
+version = "0.6.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23cdc57ce23ac53c931e88a43d06d070a6fd142f2617be5855eb75efc9beb1c2"
+dependencies = [
+ "bytecheck_derive",
+ "ptr_meta",
+ "simdutf8",
+]
+
+[[package]]
+name = "bytecheck_derive"
+version = "0.6.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3db406d29fbcd95542e92559bed4d8ad92636d1ca8b3b72ede10b4bcc010e659"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "bytecount"
 version = "0.6.8"
@@ -243,6 +309,15 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "cexpr"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fac387a98bb7c37292057cffc56d62ecb629900026402633ae9160df93a8766"
+dependencies = [
+ "nom",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -263,6 +338,17 @@ dependencies = [
  "windows-targets 0.52.5",
 ]
 
+[[package]]
+name = "clang-sys"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "67523a3b4be3ce1989d607a828d036249522dd9c1c8de7f4dd2dae43a37369d1"
+dependencies = [
+ "glob",
+ "libc",
+ "libloading",
+]
+
 [[package]]
 name = "codepage-437"
 version = "0.1.0"
@@ -447,6 +533,12 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "funty"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6d5a32815ae3f33302d95fdcb2ce17862f8c65363dcfd29360480ba1001fc9c"
+
 [[package]]
 name = "futures-channel"
 version = "0.3.30"
@@ -517,6 +609,12 @@ version = "0.28.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4271d37baee1b8c7e4b708028c57d816cf9d2434acb33a549475f78c181f6253"
 
+[[package]]
+name = "glob"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+
 [[package]]
 name = "h2"
 version = "0.4.4"
@@ -536,6 +634,15 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
+dependencies = [
+ "ahash",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.14.3"
@@ -699,7 +806,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "168fb715dda47215e360912c096649d23d58bf392ac62f73919e831745e40f26"
 dependencies = [
  "equivalent",
- "hashbrown",
+ "hashbrown 0.14.3",
 ]
 
 [[package]]
@@ -762,18 +869,61 @@ version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 
+[[package]]
+name = "lazycell"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
+
 [[package]]
 name = "libc"
 version = "0.2.153"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c198f91728a82281a64e1f4f9eeb25d82cb32a5de251c6bd1b5154d63a8e7bd"
 
+[[package]]
+name = "libloading"
+version = "0.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c2a198fb6b0eada2a8df47933734e6d35d350665a33a3593d7164fa52c75c19"
+dependencies = [
+ "cfg-if",
+ "windows-targets 0.48.5",
+]
+
 [[package]]
 name = "libm"
 version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4ec2a862134d2a7d32d7983ddcdd1c4923530833c9f2ea1a44fc5fa473989058"
 
+[[package]]
+name = "librocksdb-sys"
+version = "0.11.0+8.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3386f101bcb4bd252d8e9d2fb41ec3b0862a15a62b478c355b2982efa469e3e"
+dependencies = [
+ "bindgen",
+ "bzip2-sys",
+ "cc",
+ "glob",
+ "libc",
+ "libz-sys",
+ "lz4-sys",
+ "zstd-sys",
+]
+
+[[package]]
+name = "libz-sys"
+version = "1.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e143b5e666b2695d28f6bca6497720813f699c9602dd7f5cac91008b8ada7f9"
+dependencies = [
+ "cc",
+ "pkg-config",
+ "vcpkg",
+]
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.4.13"
@@ -796,6 +946,16 @@ version = "0.4.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "90ed8c1e510134f979dbc4f070f87d4313098b704861a105fe34231c70a3901c"
 
+[[package]]
+name = "lz4-sys"
+version = "1.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57d27b317e207b10f69f5e75494119e391a96f48861ae870d1da6edac98ca900"
+dependencies = [
+ "cc",
+ "libc",
+]
+
 [[package]]
 name = "lzma-sys"
 version = "0.1.20"
@@ -853,6 +1013,12 @@ version = "0.3.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6877bb514081ee2a7ff5ef9de3281f14a4dd4bceac4c09388074a6b5df8a139a"
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
 [[package]]
 name = "miniz_oxide"
 version = "0.7.2"
@@ -961,6 +1127,16 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2bf50223579dc7cdcfb3bfcacf7069ff68243f8c363f62ffa99cf000a6b9c451"
 
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
 [[package]]
 name = "num-complex"
 version = "0.4.5"
@@ -1144,6 +1320,12 @@ version = "1.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "de3145af08024dea9fa9914f381a17b8fc6034dfb00f3a84013f7ff43f29ed4c"
 
+[[package]]
+name = "peeking_take_while"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19b17cddbe7ec3f8bc800887bab5e717348c95ea2ca0b1bf0837fb964dc67099"
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.1"
@@ -1216,6 +1398,16 @@ version = "0.2.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
 
+[[package]]
+name = "prettyplease"
+version = "0.2.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5ac2cf0f2e4f42b49f5ffd07dae8d746508ef7526c13940e5f524012ae6c6550"
+dependencies = [
+ "proc-macro2",
+ "syn 2.0.60",
+]
+
 [[package]]
 name = "primal-check"
 version = "0.3.3"
@@ -1271,6 +1463,26 @@ dependencies = [
  "yansi",
 ]
 
+[[package]]
+name = "ptr_meta"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0738ccf7ea06b608c10564b31debd4f5bc5e197fc8bfe088f68ae5ce81e7a4f1"
+dependencies = [
+ "ptr_meta_derive",
+]
+
+[[package]]
+name = "ptr_meta_derive"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "16b845dbfca988fa33db069c0e230574d15a3088f147a87b64c7589eb662c9ac"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "pyo3"
 version = "0.21.2"
@@ -1344,6 +1556,12 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "radium"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc33ff2d4973d518d823d61aa239014831e521c75da58e3df4840d3f47749d09"
+
 [[package]]
 name = "rand"
 version = "0.8.5"
@@ -1448,6 +1666,15 @@ version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "adad44e29e4c806119491a7f06f03de4d1af22c3a680dd47f1e6e179439d1f56"
 
+[[package]]
+name = "rend"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "71fe3824f5629716b1589be05dacd749f6aa084c87e00e016714a8cdfccc997c"
+dependencies = [
+ "bytecheck",
+]
+
 [[package]]
 name = "reqwest"
 version = "0.12.4"
@@ -1490,6 +1717,35 @@ dependencies = [
  "winreg",
 ]
 
+[[package]]
+name = "rkyv"
+version = "0.7.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5cba464629b3394fc4dbc6f940ff8f5b4ff5c7aef40f29166fd4ad12acbc99c0"
+dependencies = [
+ "bitvec",
+ "bytecheck",
+ "bytes",
+ "hashbrown 0.12.3",
+ "ptr_meta",
+ "rend",
+ "rkyv_derive",
+ "seahash",
+ "tinyvec",
+ "uuid",
+]
+
+[[package]]
+name = "rkyv_derive"
+version = "0.7.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7dddfff8de25e6f62b9d64e6e432bf1c6736c57d20323e15ee10435fbda7c65"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "roaring"
 version = "0.10.3"
@@ -1500,6 +1756,16 @@ dependencies = [
  "byteorder",
 ]
 
+[[package]]
+name = "rocksdb"
+version = "0.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bb6f170a4041d50a0ce04b0d2e14916d6ca863ea2e422689a5b694395d299ffe"
+dependencies = [
+ "libc",
+ "librocksdb-sys",
+]
+
 [[package]]
 name = "roots"
 version = "0.0.8"
@@ -1512,6 +1778,12 @@ version = "0.1.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d626bb9dae77e28219937af045c257c28bfd3f69333c512553507f5f9798cb76"
 
+[[package]]
+name = "rustc-hash"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
+
 [[package]]
 name = "rustix"
 version = "0.38.34"
@@ -1571,6 +1843,12 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "seahash"
+version = "4.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1c107b6f4780854c8b126e228ea8869f4d7b71260f962fefb57b996b8959ba6b"
+
 [[package]]
 name = "security-framework"
 version = "2.10.0"
@@ -1637,6 +1915,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "shlex"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
+
 [[package]]
 name = "signal-hook-registry"
 version = "1.4.2"
@@ -1659,6 +1943,12 @@ dependencies = [
  "wide",
 ]
 
+[[package]]
+name = "simdutf8"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f27f6278552951f1f2b8cf9da965d10969b2efdea95a6ec47987ab46edfe263a"
+
 [[package]]
 name = "simple-error"
 version = "0.3.0"
@@ -1728,7 +2018,10 @@ dependencies = [
  "ouroboros",
  "piz",
  "primal-check",
+ "rayon",
+ "rkyv",
  "roaring",
+ "rocksdb",
  "roots",
  "serde",
  "serde_json",
@@ -1841,6 +2134,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "tap"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "55937e1799185b12863d447f42597ed69d9928686b8d88a1df17376a097d8369"
+
 [[package]]
 name = "target-lexicon"
 version = "0.12.14"
@@ -2077,6 +2376,12 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "uuid"
+version = "1.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a183cf7feeba97b4dd1c0d46788634f6221d87fa961b305bed08c851829efcc0"
+
 [[package]]
 name = "vcpkg"
 version = "0.2.15"
@@ -2365,6 +2670,15 @@ dependencies = [
  "windows-sys 0.48.0",
 ]
 
+[[package]]
+name = "wyz"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05f360fc0b24296329c78fda852a1e9ae82de9cf7b27dae4b7f62f118f77b9ed"
+dependencies = [
+ "tap",
+]
+
 [[package]]
 name = "xz2"
 version = "0.1.7"
diff --git a/Cargo.toml b/Cargo.toml
index 7bd4baf..8ad2f93 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,7 +12,7 @@ crate-type = ["cdylib"]
 pyo3 = { version = "0.21.2", features = ["extension-module", "anyhow"] }
 rayon = "1.10.0"
 serde = { version = "1.0.198", features = ["derive"] }
-sourmash = { version = "0.13.1"}
+sourmash = { version = "0.13.1", features=["branchwater"]}
 serde_json = "1.0.116"
 niffler = "2.4.0"
 needletail = "0.5.1"