Adapt Garage to use new DB abstraction

26 files changed, 355 insertions, 214 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 1f81ebec..e7b41248 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -889,6 +889,7 @@ dependencies = [
  "futures",
  "futures-util",
  "garage_api",
+ "garage_db",
  "garage_model 0.7.0",
  "garage_rpc 0.7.0",
  "garage_table 0.7.0",
@@ -972,6 +973,7 @@ dependencies = [
  "bytes 1.1.0",
  "futures",
  "futures-util",
+ "garage_db",
  "garage_rpc 0.7.0",
  "garage_table 0.7.0",
  "garage_util 0.7.0",
@@ -981,7 +983,6 @@ dependencies = [
  "rmp-serde 0.15.5",
  "serde",
  "serde_bytes",
- "sled",
  "tokio",
  "tracing",
  "zstd",
@@ -1034,6 +1035,7 @@ dependencies = [
  "futures",
  "futures-util",
  "garage_block",
+ "garage_db",
  "garage_model 0.5.1",
  "garage_rpc 0.7.0",
  "garage_table 0.7.0",
@@ -1045,7 +1047,6 @@ dependencies = [
  "rmp-serde 0.15.5",
  "serde",
  "serde_bytes",
- "sled",
  "tokio",
  "tracing",
  "zstd",
@@ -1149,7 +1150,6 @@ dependencies = [
  "rmp-serde 0.15.5",
  "serde",
  "serde_bytes",
- "sled",
  "tokio",
  "tracing",
 ]
@@ -1188,6 +1188,7 @@ dependencies = [
  "chrono",
  "err-derive 0.3.1",
  "futures",
+ "garage_db",
  "hex",
  "http",
  "hyper",
@@ -1198,7 +1199,6 @@ dependencies = [
  "serde",
  "serde_json",
  "sha2",
- "sled",
  "tokio",
  "toml",
  "tracing",
diff --git a/src/block/Cargo.toml b/src/block/Cargo.toml
index 9cba69ee..80346aca 100644
--- a/src/block/Cargo.toml
+++ b/src/block/Cargo.toml
@@ -14,6 +14,7 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+garage_db = { version = "0.8.0", path = "../db" }
 garage_rpc = { version = "0.7.0", path = "../rpc" }
 garage_util = { version = "0.7.0", path = "../util" }
 garage_table = { version = "0.7.0", path = "../table" }
@@ -27,8 +28,6 @@ tracing = "0.1.30"
 rand = "0.8"
 zstd = { version = "0.9", default-features = false }
 
-sled = "0.34"
-
 rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"
diff --git a/src/block/manager.rs b/src/block/manager.rs
index 9b2d9cad..50039d2b 100644
--- a/src/block/manager.rs
+++ b/src/block/manager.rs
@@ -17,10 +17,11 @@ use opentelemetry::{
 	Context, KeyValue,
 };
 
+use garage_db as db;
+
 use garage_util::data::*;
 use garage_util::error::*;
 use garage_util::metrics::RecordDuration;
-use garage_util::sled_counter::SledCountedTree;
 use garage_util::time::*;
 use garage_util::tranquilizer::Tranquilizer;
 
@@ -91,9 +92,9 @@ pub struct BlockManager {
 
 	rc: BlockRc,
 
-	resync_queue: SledCountedTree,
+	resync_queue: db::Tree,
 	resync_notify: Notify,
-	resync_errors: SledCountedTree,
+	resync_errors: db::Tree,
 
 	system: Arc<System>,
 	endpoint: Arc<Endpoint<BlockRpc, Self>>,
@@ -108,7 +109,7 @@ struct BlockManagerLocked();
 
 impl BlockManager {
 	pub fn new(
-		db: &sled::Db,
+		db: &db::Db,
 		data_dir: PathBuf,
 		compression_level: Option<i32>,
 		background_tranquility: u32,
@@ -123,12 +124,10 @@ impl BlockManager {
 		let resync_queue = db
 			.open_tree("block_local_resync_queue")
 			.expect("Unable to open block_local_resync_queue tree");
-		let resync_queue = SledCountedTree::new(resync_queue);
 
 		let resync_errors = db
 			.open_tree("block_local_resync_errors")
 			.expect("Unable to open block_local_resync_errors tree");
-		let resync_errors = SledCountedTree::new(resync_errors);
 
 		let endpoint = system
 			.netapp
@@ -219,7 +218,7 @@ impl BlockManager {
 	/// to fix any mismatch between the two.
 	pub async fn repair_data_store(&self, must_exit: &watch::Receiver<bool>) -> Result<(), Error> {
 		// 1. Repair blocks from RC table.
-		for (i, entry) in self.rc.rc.iter().enumerate() {
+		for (i, entry) in self.rc.rc.iter()?.enumerate() {
 			let (hash, _) = entry?;
 			let hash = Hash::try_from(&hash[..]).unwrap();
 			self.put_to_resync(&hash, Duration::from_secs(0))?;
@@ -265,17 +264,17 @@ impl BlockManager {
 
 	/// Get lenght of resync queue
 	pub fn resync_queue_len(&self) -> usize {
-		self.resync_queue.len()
+		self.resync_queue.len().unwrap() // TODO fix unwrap
 	}
 
 	/// Get number of blocks that have an error
 	pub fn resync_errors_len(&self) -> usize {
-		self.resync_errors.len()
+		self.resync_errors.len().unwrap() // TODO fix unwrap
 	}
 
 	/// Get number of items in the refcount table
 	pub fn rc_len(&self) -> usize {
-		self.rc.rc.len()
+		self.rc.rc.len().unwrap() // TODO fix unwrap
 	}
 
 	//// ----- Managing the reference counter ----
@@ -503,12 +502,12 @@ impl BlockManager {
 		});
 	}
 
-	fn put_to_resync(&self, hash: &Hash, delay: Duration) -> Result<(), sled::Error> {
+	fn put_to_resync(&self, hash: &Hash, delay: Duration) -> Result<(), db::Error> {
 		let when = now_msec() + delay.as_millis() as u64;
 		self.put_to_resync_at(hash, when)
 	}
 
-	fn put_to_resync_at(&self, hash: &Hash, when: u64) -> Result<(), sled::Error> {
+	fn put_to_resync_at(&self, hash: &Hash, when: u64) -> Result<(), db::Error> {
 		trace!("Put resync_queue: {} {:?}", when, hash);
 		let mut key = u64::to_be_bytes(when).to_vec();
 		key.extend(hash.as_ref());
@@ -547,11 +546,8 @@ impl BlockManager {
 	// - Ok(true) -> a block was processed (successfully or not)
 	// - Ok(false) -> no block was processed, but we are ready for the next iteration
 	// - Err(_) -> a Sled error occurred when reading/writing from resync_queue/resync_errors
-	async fn resync_iter(
-		&self,
-		must_exit: &mut watch::Receiver<bool>,
-	) -> Result<bool, sled::Error> {
-		if let Some(first_pair_res) = self.resync_queue.iter().next() {
+	async fn resync_iter(&self, must_exit: &mut watch::Receiver<bool>) -> Result<bool, db::Error> {
+		if let Some(first_pair_res) = self.resync_queue.iter()?.next() {
 			let (time_bytes, hash_bytes) = first_pair_res?;
 
 			let time_msec = u64::from_be_bytes(time_bytes[0..8].try_into().unwrap());
@@ -966,7 +962,7 @@ impl ErrorCounter {
 		}
 	}
 
-	fn decode(data: sled::IVec) -> Self {
+	fn decode<'a>(data: db::Value<'a>) -> Self {
 		Self {
 			errors: u64::from_be_bytes(data[0..8].try_into().unwrap()),
 			last_try: u64::from_be_bytes(data[8..16].try_into().unwrap()),
diff --git a/src/block/metrics.rs b/src/block/metrics.rs
index f0f541a3..1d4d0028 100644
--- a/src/block/metrics.rs
+++ b/src/block/metrics.rs
@@ -1,6 +1,6 @@
 use opentelemetry::{global, metrics::*};
 
-use garage_util::sled_counter::SledCountedTree;
+use garage_db as db;
 
 /// TableMetrics reference all counter used for metrics
 pub struct BlockManagerMetrics {
@@ -23,12 +23,12 @@ pub struct BlockManagerMetrics {
 }
 
 impl BlockManagerMetrics {
-	pub fn new(resync_queue: SledCountedTree, resync_errors: SledCountedTree) -> Self {
+	pub fn new(resync_queue: db::Tree, resync_errors: db::Tree) -> Self {
 		let meter = global::meter("garage_model/block");
 		Self {
 			_resync_queue_len: meter
 				.u64_value_observer("block.resync_queue_length", move |observer| {
-					observer.observe(resync_queue.len() as u64, &[])
+					observer.observe(resync_queue.len().unwrap() as u64, &[]) // TODO fix unwrap
 				})
 				.with_description(
 					"Number of block hashes queued for local check and possible resync",
@@ -36,7 +36,7 @@ impl BlockManagerMetrics {
 				.init(),
 			_resync_errored_blocks: meter
 				.u64_value_observer("block.resync_errored_blocks", move |observer| {
-					observer.observe(resync_errors.len() as u64, &[])
+					observer.observe(resync_errors.len().unwrap() as u64, &[]) // TODO fix unwrap
 				})
 				.with_description("Number of block hashes whose last resync resulted in an error")
 				.init(),
diff --git a/src/block/rc.rs b/src/block/rc.rs
index ec3ea44e..f6d8c2aa 100644
--- a/src/block/rc.rs
+++ b/src/block/rc.rs
@@ -1,5 +1,7 @@
 use std::convert::TryInto;
 
+use garage_db as db;
+
 use garage_util::data::*;
 use garage_util::error::*;
 use garage_util::time::*;
@@ -7,31 +9,47 @@ use garage_util::time::*;
 use crate::manager::BLOCK_GC_DELAY;
 
 pub struct BlockRc {
-	pub(crate) rc: sled::Tree,
+	pub(crate) rc: db::Tree,
 }
 
 impl BlockRc {
-	pub(crate) fn new(rc: sled::Tree) -> Self {
+	pub(crate) fn new(rc: db::Tree) -> Self {
 		Self { rc }
 	}
 
 	/// Increment the reference counter associated to a hash.
 	/// Returns true if the RC goes from zero to nonzero.
 	pub(crate) fn block_incref(&self, hash: &Hash) -> Result<bool, Error> {
-		let old_rc = self
-			.rc
-			.fetch_and_update(&hash, |old| RcEntry::parse_opt(old).increment().serialize())?;
-		let old_rc = RcEntry::parse_opt(old_rc);
+		let old_rc = self.rc.db().transaction(|tx| {
+			let old_rc = RcEntry::parse_opt(tx.get(&self.rc, &hash)?);
+			match old_rc.increment().serialize() {
+				Some(x) => {
+					tx.insert(&self.rc, &hash, x)?;
+				}
+				None => {
+					tx.remove(&self.rc, &hash)?;
+				}
+			};
+			tx.commit(old_rc)
+		})?;
 		Ok(old_rc.is_zero())
 	}
 
 	/// Decrement the reference counter associated to a hash.
 	/// Returns true if the RC is now zero.
 	pub(crate) fn block_decref(&self, hash: &Hash) -> Result<bool, Error> {
-		let new_rc = self
-			.rc
-			.update_and_fetch(&hash, |old| RcEntry::parse_opt(old).decrement().serialize())?;
-		let new_rc = RcEntry::parse_opt(new_rc);
+		let new_rc = self.rc.db().transaction(|tx| {
+			let new_rc = RcEntry::parse_opt(tx.get(&self.rc, &hash)?).decrement();
+			match new_rc.serialize() {
+				Some(x) => {
+					tx.insert(&self.rc, &hash, x)?;
+				}
+				None => {
+					tx.remove(&self.rc, &hash)?;
+				}
+			};
+			tx.commit(new_rc)
+		})?;
 		Ok(matches!(new_rc, RcEntry::Deletable { .. }))
 	}
 
@@ -44,12 +62,15 @@ impl BlockRc {
 	/// deletion time has passed
 	pub(crate) fn clear_deleted_block_rc(&self, hash: &Hash) -> Result<(), Error> {
 		let now = now_msec();
-		self.rc.update_and_fetch(&hash, |rcval| {
-			let updated = match RcEntry::parse_opt(rcval) {
-				RcEntry::Deletable { at_time } if now > at_time => RcEntry::Absent,
-				v => v,
+		self.rc.db().transaction(|tx| {
+			let rcval = RcEntry::parse_opt(tx.get(&self.rc, &hash)?);
+			match rcval {
+				RcEntry::Deletable { at_time } if now > at_time => {
+					tx.remove(&self.rc, &hash)?;
+				}
+				_ => (),
 			};
-			updated.serialize()
+			tx.commit(())
 		})?;
 		Ok(())
 	}
diff --git a/src/db/lib.rs b/src/db/lib.rs
index 4e400a1d..75c6ffa2 100644
--- a/src/db/lib.rs
+++ b/src/db/lib.rs
@@ -3,26 +3,31 @@ pub mod sled_adapter;
 #[cfg(test)]
 pub mod test;
 
+use core::ops::{Bound, RangeBounds};
+
 use std::borrow::Cow;
 use std::sync::Arc;
 
 use arc_swap::ArcSwapOption;
+use err_derive::Error;
 
 #[derive(Clone)]
 pub struct Db(pub(crate) Arc<dyn IDb>);
 
-#[derive(Clone)]
+#[derive(Clone, Copy)]
 pub struct Transaction<'a>(pub(crate) &'a dyn ITx<'a>);
 
 #[derive(Clone)]
 pub struct Tree(pub(crate) Arc<dyn IDb>, pub(crate) usize);
 
 pub type Value<'a> = Cow<'a, [u8]>;
-pub type ValueIter<'a> = Box<dyn std::iter::Iterator<Item = Result<(Value<'a>, Value<'a>)>> + 'a>;
+pub type ValueIter<'a> =
+	Box<dyn std::iter::Iterator<Item = Result<(Value<'a>, Value<'a>)>> + Send + Sync + 'a>;
 
 // ----
 
-#[derive(Debug)]
+#[derive(Debug, Error)]
+#[error(display = "{}", _0)]
 pub struct Error(Cow<'static, str>);
 
 pub type Result<T> = std::result::Result<T, Error>;
@@ -43,14 +48,14 @@ impl<E> From<Error> for TxError<E> {
 // ----
 
 impl Db {
-	pub fn tree<S: AsRef<str>>(&self, name: S) -> Result<Tree> {
-		let tree_id = self.0.tree(name.as_ref())?;
+	pub fn open_tree<S: AsRef<str>>(&self, name: S) -> Result<Tree> {
+		let tree_id = self.0.open_tree(name.as_ref())?;
 		Ok(Tree(self.0.clone(), tree_id))
 	}
 
 	pub fn transaction<R, E, F>(&self, fun: F) -> TxResult<R, E>
 	where
-		F: Fn(Transaction<'_>) -> TxResult<R, E> + Send + Sync,
+		F: Fn(Transaction<'_>) -> TxResult<R, E>,
 		R: Send + Sync,
 		E: Send + Sync,
 	{
@@ -83,20 +88,50 @@ impl Db {
 }
 
 impl Tree {
+	pub fn db(&self) -> Db {
+		Db(self.0.clone())
+	}
+
 	pub fn get<'a, T: AsRef<[u8]>>(&'a self, key: T) -> Result<Option<Value<'a>>> {
 		self.0.get(self.1, key.as_ref())
 	}
 
-	pub fn put<T: AsRef<[u8]>, U: AsRef<[u8]>>(&self, key: T, value: U) -> Result<()> {
-		self.0.put(self.1, key.as_ref(), value.as_ref())
+	pub fn len(&self) -> Result<usize> {
+		self.0.len(self.1)
+	}
+
+	pub fn insert<T: AsRef<[u8]>, U: AsRef<[u8]>>(&self, key: T, value: U) -> Result<()> {
+		self.0.insert(self.1, key.as_ref(), value.as_ref())
 	}
 
-	pub fn iter<'a>(&'a self, reverse: bool) -> Result<ValueIter<'a>> {
-		self.0.range(self.1, None, reverse)
+	pub fn remove<'a, T: AsRef<[u8]>>(&'a self, key: T) -> Result<bool> {
+		self.0.remove(self.1, key.as_ref())
 	}
 
-	pub fn range<'a, T: AsRef<[u8]>>(&'a self, start: T, reverse: bool) -> Result<ValueIter<'a>> {
-		self.0.range(self.1, Some(start.as_ref()), reverse)
+	pub fn iter<'a>(&'a self) -> Result<ValueIter<'a>> {
+		self.0.iter(self.1)
+	}
+	pub fn iter_rev<'a>(&'a self) -> Result<ValueIter<'a>> {
+		self.0.iter_rev(self.1)
+	}
+
+	pub fn range<'a, K, R>(&'a self, range: R) -> Result<ValueIter<'a>>
+	where
+		K: AsRef<[u8]>,
+		R: RangeBounds<K>,
+	{
+		let sb = range.start_bound();
+		let eb = range.end_bound();
+		self.0.range(self.1, get_bound(sb), get_bound(eb))
+	}
+	pub fn range_rev<'a, K, R>(&'a self, range: R) -> Result<ValueIter<'a>>
+	where
+		K: AsRef<[u8]>,
+		R: RangeBounds<K>,
+	{
+		let sb = range.start_bound();
+		let eb = range.end_bound();
+		self.0.range_rev(self.1, get_bound(sb), get_bound(eb))
 	}
 }
 
@@ -105,8 +140,17 @@ impl<'a> Transaction<'a> {
 		self.0.get(tree.1, key.as_ref())
 	}
 
-	pub fn put<T: AsRef<[u8]>, U: AsRef<[u8]>>(&self, tree: &Tree, key: T, value: U) -> Result<()> {
-		self.0.put(tree.1, key.as_ref(), value.as_ref())
+	pub fn insert<T: AsRef<[u8]>, U: AsRef<[u8]>>(
+		&self,
+		tree: &Tree,
+		key: T,
+		value: U,
+	) -> Result<()> {
+		self.0.insert(tree.1, key.as_ref(), value.as_ref())
+	}
+
+	pub fn remove<T: AsRef<[u8]>>(&self, tree: &Tree, key: T) -> Result<bool> {
+		self.0.remove(tree.1, key.as_ref())
 	}
 
 	#[must_use]
@@ -131,15 +175,28 @@ impl<'a> Transaction<'a> {
 // ---- Internal interfaces
 
 pub(crate) trait IDb: Send + Sync {
-	fn tree(&self, name: &str) -> Result<usize>;
+	fn open_tree(&self, name: &str) -> Result<usize>;
 
 	fn get<'a>(&'a self, tree: usize, key: &[u8]) -> Result<Option<Value<'a>>>;
-	fn put(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()>;
-	fn range<'a>(
+	fn len(&self, tree: usize) -> Result<usize>;
+
+	fn insert(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()>;
+	fn remove(&self, tree: usize, key: &[u8]) -> Result<bool>;
+
+	fn iter<'a>(&'a self, tree: usize) -> Result<ValueIter<'a>>;
+	fn iter_rev<'a>(&'a self, tree: usize) -> Result<ValueIter<'a>>;
+
+	fn range<'a, 'r>(
+		&'a self,
+		tree: usize,
+		low: Bound<&'r [u8]>,
+		high: Bound<&'r [u8]>,
+	) -> Result<ValueIter<'a>>;
+	fn range_rev<'a, 'r>(
 		&'a self,
 		tree: usize,
-		start: Option<&[u8]>,
-		reverse: bool,
+		low: Bound<&'r [u8]>,
+		high: Bound<&'r [u8]>,
 	) -> Result<ValueIter<'a>>;
 
 	fn transaction(&self, f: &dyn ITxFn) -> TxResult<(), ()>;
@@ -147,10 +204,11 @@ pub(crate) trait IDb: Send + Sync {
 
 pub(crate) trait ITx<'a> {
 	fn get(&self, tree: usize, key: &[u8]) -> Result<Option<Value<'a>>>;
-	fn put(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()>;
+	fn insert(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()>;
+	fn remove(&self, tree: usize, key: &[u8]) -> Result<bool>;
 }
 
-pub(crate) trait ITxFn: Send + Sync {
+pub(crate) trait ITxFn {
 	fn try_on<'a>(&'a self, tx: &'a dyn ITx<'a>) -> TxFnResult;
 }
 
@@ -162,7 +220,7 @@ enum TxFnResult {
 
 struct TxFn<F, R, E>
 where
-	F: Fn(Transaction<'_>) -> TxResult<R, E> + Send + Sync,
+	F: Fn(Transaction<'_>) -> TxResult<R, E>,
 	R: Send + Sync,
 	E: Send + Sync,
 {
@@ -172,7 +230,7 @@ where
 
 impl<F, R, E> ITxFn for TxFn<F, R, E>
 where
-	F: Fn(Transaction<'_>) -> TxResult<R, E> + Send + Sync,
+	F: Fn(Transaction<'_>) -> TxResult<R, E>,
 	R: Send + Sync,
 	E: Send + Sync,
 {
@@ -187,3 +245,13 @@ where
 		retval
 	}
 }
+
+// ----
+
+fn get_bound<K: AsRef<[u8]>>(b: Bound<&K>) -> Bound<&[u8]> {
+	match b {
+		Bound::Included(v) => Bound::Included(v.as_ref()),
+		Bound::Excluded(v) => Bound::Excluded(v.as_ref()),
+		Bound::Unbounded => Bound::Unbounded,
+	}
+}
diff --git a/src/db/sled_adapter.rs b/src/db/sled_adapter.rs
index 6e375f03..b1da1c2b 100644
--- a/src/db/sled_adapter.rs
+++ b/src/db/sled_adapter.rs
@@ -1,3 +1,5 @@
+use core::ops::Bound;
+
 use std::collections::HashMap;
 use std::sync::{Arc, RwLock};
 
@@ -42,7 +44,7 @@ impl SledDb {
 }
 
 impl IDb for SledDb {
-	fn tree(&self, name: &str) -> Result<usize> {
+	fn open_tree(&self, name: &str) -> Result<usize> {
 		let mut trees = self.trees.write().unwrap();
 		if let Some(i) = trees.1.get(name) {
 			Ok(*i)
@@ -60,42 +62,63 @@ impl IDb for SledDb {
 		Ok(tree.get(key)?.map(|v| v.to_vec().into()))
 	}
 
-	fn put(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()> {
+	fn remove(&self, tree: usize, key: &[u8]) -> Result<bool> {
+		let tree = self.get_tree(tree)?;
+		Ok(tree.remove(key)?.is_some())
+	}
+
+	fn len(&self, tree: usize) -> Result<usize> {
+		let tree = self.get_tree(tree)?;
+		Ok(tree.len())
+	}
+
+	fn insert(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()> {
 		let tree = self.get_tree(tree)?;
 		tree.insert(key, value)?;
 		Ok(())
 	}
 
-	fn range<'a>(
+	fn iter<'a>(&'a self, tree: usize) -> Result<ValueIter<'a>> {
+		let tree = self.get_tree(tree)?;
+		Ok(Box::new(tree.iter().map(|v| {
+			v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
+				.map_err(Into::into)
+		})))
+	}
+
+	fn iter_rev<'a>(&'a self, tree: usize) -> Result<ValueIter<'a>> {
+		let tree = self.get_tree(tree)?;
+		Ok(Box::new(tree.iter().rev().map(|v| {
+			v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
+				.map_err(Into::into)
+		})))
+	}
+
+	fn range<'a, 'r>(
 		&'a self,
 		tree: usize,
-		start: Option<&[u8]>,
-		reverse: bool,
+		low: Bound<&'r [u8]>,
+		high: Bound<&'r [u8]>,
 	) -> Result<ValueIter<'a>> {
 		let tree = self.get_tree(tree)?;
-		if reverse {
-			match start {
-				Some(start) => Ok(Box::new(tree.range(..=start).rev().map(|v| {
-					v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
-						.map_err(Into::into)
-				}))),
-				None => Ok(Box::new(tree.iter().rev().map(|v| {
-					v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
-						.map_err(Into::into)
-				}))),
-			}
-		} else {
-			match start {
-				Some(start) => Ok(Box::new(tree.range(start..).map(|v| {
-					v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
-						.map_err(Into::into)
-				}))),
-				None => Ok(Box::new(tree.iter().map(|v| {
-					v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
-						.map_err(Into::into)
-				}))),
-			}
-		}
+		Ok(Box::new(tree.range::<&'r [u8], _>((low, high)).map(|v| {
+			v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
+				.map_err(Into::into)
+		})))
+	}
+	fn range_rev<'a, 'r>(
+		&'a self,
+		tree: usize,
+		low: Bound<&'r [u8]>,
+		high: Bound<&'r [u8]>,
+	) -> Result<ValueIter<'a>> {
+		let tree = self.get_tree(tree)?;
+		Ok(Box::new(tree.range::<&'r [u8], _>((low, high)).rev().map(
+			|v| {
+				v.map(|(x, y)| (x.to_vec().into(), y.to_vec().into()))
+					.map_err(Into::into)
+			},
+		)))
 	}
 
 	fn transaction(&self, f: &dyn ITxFn) -> TxResult<(), ()> {
@@ -162,7 +185,7 @@ impl<'a> ITx<'a> for SledTx<'a> {
 		Ok(tmp.map(|v| v.to_vec().into()))
 	}
 
-	fn put(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()> {
+	fn insert(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<()> {
 		let tree = self
 			.trees
 			.get(tree)
@@ -170,4 +193,12 @@ impl<'a> ITx<'a> for SledTx<'a> {
 		self.save_error(tree.insert(key, value))?;
 		Ok(())
 	}
+
+	fn remove(&self, tree: usize, key: &[u8]) -> Result<bool> {
+		let tree = self
+			.trees
+			.get(tree)
+			.ok_or(Error("invalid tree id".into()))?;
+		Ok(self.save_error(tree.remove(key))?.is_some())
+	}
 }
diff --git a/src/db/test.rs b/src/db/test.rs
index 7e389271..69e1d12c 100644
--- a/src/db/test.rs
+++ b/src/db/test.rs
@@ -3,21 +3,22 @@ use crate::*;
 use crate::sled_adapter::SledDb;
 
 fn test_suite(db: Db) -> Result<()> {
-	let tree = db.tree("tree")?;
+	let tree = db.open_tree("tree")?;
 
 	let ka: &[u8] = &b"test"[..];
 	let kb: &[u8] = &b"zwello"[..];
+	let kint: &[u8] = &b"tz"[..];
 	let va: &[u8] = &b"plop"[..];
 	let vb: &[u8] = &b"plip"[..];
 	let vc: &[u8] = &b"plup"[..];
 
-	tree.put(ka, va)?;
+	tree.insert(ka, va)?;
 	assert_eq!(tree.get(ka)?, Some(va.into()));
 
 	let res = db.transaction::<_, (), _>(|tx| {
 		assert_eq!(tx.get(&tree, ka)?, Some(va.into()));
 
-		tx.put(&tree, ka, vb)?;
+		tx.insert(&tree, ka, vb)?;
 
 		assert_eq!(tx.get(&tree, ka)?, Some(vb.into()));
 
@@ -29,7 +30,7 @@ fn test_suite(db: Db) -> Result<()> {
 	let res = db.transaction::<(), _, _>(|tx| {
 		assert_eq!(tx.get(&tree, ka)?, Some(vb.into()));
 
-		tx.put(&tree, ka, vc)?;
+		tx.insert(&tree, ka, vc)?;
 
 		assert_eq!(tx.get(&tree, ka)?, Some(vc.into()));
 
@@ -38,27 +39,27 @@ fn test_suite(db: Db) -> Result<()> {
 	assert!(matches!(res, Err(TxError::Abort(42))));
 	assert_eq!(tree.get(ka)?, Some(vb.into()));
 
-	let mut iter = tree.iter(false)?;
+	let mut iter = tree.iter()?;
 	assert_eq!(iter.next().unwrap().unwrap(), (ka.into(), vb.into()));
 	assert!(iter.next().is_none());
 
-	tree.put(kb, vc)?;
+	tree.insert(kb, vc)?;
 	assert_eq!(tree.get(kb)?, Some(vc.into()));
 
-	let mut iter = tree.iter(false)?;
+	let mut iter = tree.iter()?;
 	assert_eq!(iter.next().unwrap().unwrap(), (ka.into(), vb.into()));
 	assert_eq!(iter.next().unwrap().unwrap(), (kb.into(), vc.into()));
 	assert!(iter.next().is_none());
 
-	let mut iter = tree.range("tz", false)?;
+	let mut iter = tree.range(kint..)?;
 	assert_eq!(iter.next().unwrap().unwrap(), (kb.into(), vc.into()));
 	assert!(iter.next().is_none());
 
-	let mut iter = tree.range("tz", true)?;
+	let mut iter = tree.range_rev(..kint)?;
 	assert_eq!(iter.next().unwrap().unwrap(), (ka.into(), vb.into()));
 	assert!(iter.next().is_none());
 
-	let mut iter = tree.iter(true)?;
+	let mut iter = tree.iter_rev()?;
 	assert_eq!(iter.next().unwrap().unwrap(), (kb.into(), vc.into()));
 	assert_eq!(iter.next().unwrap().unwrap(), (ka.into(), vb.into()));
 	assert!(iter.next().is_none());
diff --git a/src/garage/Cargo.toml b/src/garage/Cargo.toml
index 902f67f8..d34a7fa4 100644
--- a/src/garage/Cargo.toml
+++ b/src/garage/Cargo.toml
@@ -21,6 +21,7 @@ path = "tests/lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+garage_db = { version = "0.8.0", path = "../db" }
 garage_api = { version = "0.7.0", path = "../api" }
 garage_model = { version = "0.7.0", path = "../model" }
 garage_rpc = { version = "0.7.0", path = "../rpc" }
diff --git a/src/garage/admin.rs b/src/garage/admin.rs
index bc1f494a..cce88b35 100644
--- a/src/garage/admin.rs
+++ b/src/garage/admin.rs
@@ -727,7 +727,7 @@ impl AdminRpcHandler {
 	{
 		writeln!(to, "\nTable stats for {}", F::TABLE_NAME).unwrap();
 		if opt.detailed {
-			writeln!(to, "  number of items: {}", t.data.store.len()).unwrap();
+			writeln!(to, "  number of items: {}", t.data.store.len().unwrap()).unwrap(); // TODO fix len unwrap
 			writeln!(
 				to,
 				"  Merkle tree size: {}",
diff --git a/src/garage/repair.rs b/src/garage/repair.rs
index 830eac71..04d9ee72 100644
--- a/src/garage/repair.rs
+++ b/src/garage/repair.rs
@@ -1,3 +1,4 @@
+use core::ops::Bound;
 use std::sync::Arc;
 
 use tokio::sync::watch;
@@ -65,9 +66,15 @@ impl Repair {
 	async fn repair_versions(&self, must_exit: &watch::Receiver<bool>) -> Result<(), Error> {
 		let mut pos = vec![];
 
-		while let Some((item_key, item_bytes)) =
-			self.garage.version_table.data.store.get_gt(&pos)?
+		while let Some(item) = self
+			.garage
+			.version_table
+			.data
+			.store
+			.range((Bound::Excluded(pos), Bound::Unbounded))?
+			.next()
 		{
+			let (item_key, item_bytes) = item?;
 			pos = item_key.to_vec();
 
 			let version = rmp_serde::decode::from_read_ref::<_, Version>(item_bytes.as_ref())?;
@@ -109,9 +116,16 @@ impl Repair {
 	async fn repair_block_ref(&self, must_exit: &watch::Receiver<bool>) -> Result<(), Error> {
 		let mut pos = vec![];
 
-		while let Some((item_key, item_bytes)) =
-			self.garage.block_ref_table.data.store.get_gt(&pos)?
+		while let Some(item) = self
+			.garage
+			.block_ref_table
+			.data
+			.store
+			.range((Bound::Excluded(pos), Bound::Unbounded))?
+			.next()
 		{
+			let (item_key, item_bytes) = item?;
+
 			pos = item_key.to_vec();
 
 			let block_ref = rmp_serde::decode::from_read_ref::<_, BlockRef>(item_bytes.as_ref())?;
diff --git a/src/garage/server.rs b/src/garage/server.rs
index b58ad286..69f5d60c 100644
--- a/src/garage/server.rs
+++ b/src/garage/server.rs
@@ -38,6 +38,7 @@ pub async fn run_server(config_file: PathBuf) -> Result<(), Error> {
 		.flush_every_ms(Some(config.sled_flush_every_ms))
 		.open()
 		.expect("Unable to open sled DB");
+	let db = garage_db::sled_adapter::SledDb::new(db);
 
 	info!("Initializing background runner...");
 	let watch_cancel = netapp::util::watch_ctrl_c();
diff --git a/src/model/Cargo.toml b/src/model/Cargo.toml
index 133fe44e..d908dc01 100644
--- a/src/model/Cargo.toml
+++ b/src/model/Cargo.toml
@@ -14,6 +14,7 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+garage_db = { version = "0.8.0", path = "../db" }
 garage_rpc = { version = "0.7.0", path = "../rpc" }
 garage_table = { version = "0.7.0", path = "../table" }
 garage_block = { version = "0.7.0", path = "../block" }
@@ -30,8 +31,6 @@ tracing = "0.1.30"
 rand = "0.8"
 zstd = { version = "0.9", default-features = false }
 
-sled = "0.34"
-
 rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"
diff --git a/src/model/garage.rs b/src/model/garage.rs
index 2f99bd68..280f3dc7 100644
--- a/src/model/garage.rs
+++ b/src/model/garage.rs
@@ -2,6 +2,8 @@ use std::sync::Arc;
 
 use netapp::NetworkKey;
 
+use garage_db as db;
+
 use garage_util::background::*;
 use garage_util::config::*;
 
@@ -33,7 +35,7 @@ pub struct Garage {
 	pub config: Config,
 
 	/// The local database
-	pub db: sled::Db,
+	pub db: db::Db,
 	/// A background job runner
 	pub background: Arc<BackgroundRunner>,
 	/// The membership manager
@@ -71,7 +73,7 @@ pub struct GarageK2V {
 
 impl Garage {
 	/// Create and run garage
-	pub fn new(config: Config, db: sled::Db, background: Arc<BackgroundRunner>) -> Arc<Self> {
+	pub fn new(config: Config, db: db::Db, background: Arc<BackgroundRunner>) -> Arc<Self> {
 		let network_key = NetworkKey::from_slice(
 			&hex::decode(&config.rpc_secret).expect("Invalid RPC secret key")[..],
 		)
@@ -199,7 +201,7 @@ impl Garage {
 
 #[cfg(feature = "k2v")]
 impl GarageK2V {
-	fn new(system: Arc<System>, db: &sled::Db, meta_rep_param: TableShardedReplication) -> Self {
+	fn new(system: Arc<System>, db: &db::Db, meta_rep_param: TableShardedReplication) -> Self {
 		info!("Initialize K2V counter table...");
 		let counter_table = IndexCounter::new(system.clone(), meta_rep_param.clone(), db);
 		info!("Initialize K2V subscription manager...");
diff --git a/src/model/index_counter.rs b/src/model/index_counter.rs
index 123154d4..33de797d 100644
--- a/src/model/index_counter.rs
+++ b/src/model/index_counter.rs
@@ -6,6 +6,8 @@ use std::time::Duration;
 use serde::{Deserialize, Serialize};
 use tokio::sync::{mpsc, watch};
 
+use garage_db as db;
+
 use garage_rpc::ring::Ring;
 use garage_rpc::system::System;
 use garage_util::data::*;
@@ -135,7 +137,7 @@ impl<T: CounterSchema> TableSchema for CounterTable<T> {
 
 pub struct IndexCounter<T: CounterSchema> {
 	this_node: Uuid,
-	local_counter: sled::Tree,
+	local_counter: db::Tree,
 	propagate_tx: mpsc::UnboundedSender<(T::P, T::S, LocalCounterEntry)>,
 	pub table: Arc<Table<CounterTable<T>, TableShardedReplication>>,
 }
@@ -144,7 +146,7 @@ impl<T: CounterSchema> IndexCounter<T> {
 	pub fn new(
 		system: Arc<System>,
 		replication: TableShardedReplication,
-		db: &sled::Db,
+		db: &db::Db,
 	) -> Arc<Self> {
 		let background = system.background.clone();
 
@@ -177,12 +179,12 @@ impl<T: CounterSchema> IndexCounter<T> {
 	pub fn count(&self, pk: &T::P, sk: &T::S, counts: &[(&str, i64)]) -> Result<(), Error> {
 		let tree_key = self.table.data.tree_key(pk, sk);
 
-		let new_entry = self.local_counter.transaction(|tx| {
-			let mut entry = match tx.get(&tree_key[..])? {
+		let new_entry = self.local_counter.db().transaction(|tx| {
+			let mut entry = match tx.get(&self.local_counter, &tree_key[..])? {
 				Some(old_bytes) => {
 					rmp_serde::decode::from_read_ref::<_, LocalCounterEntry>(&old_bytes)
 						.map_err(Error::RmpDecode)
-						.map_err(sled::transaction::ConflictableTransactionError::Abort)?
+						.map_err(db::TxError::Abort)?
 				}
 				None => LocalCounterEntry {
 					values: BTreeMap::new(),
@@ -197,8 +199,8 @@ impl<T: CounterSchema> IndexCounter<T> {
 
 			let new_entry_bytes = rmp_to_vec_all_named(&entry)
 				.map_err(Error::RmpEncode)
-				.map_err(sled::transaction::ConflictableTransactionError::Abort)?;
-			tx.insert(&tree_key[..], new_entry_bytes)?;
+				.map_err(db::TxError::Abort)?;
+			tx.insert(&self.local_counter, &tree_key[..], new_entry_bytes)?;
 
 			Ok(entry)
 		})?;
diff --git a/src/model/migrate.rs b/src/model/migrate.rs
index 7e61957a..1f063265 100644
--- a/src/model/migrate.rs
+++ b/src/model/migrate.rs
@@ -25,7 +25,7 @@ impl Migrate {
 			.open_tree("bucket:table")
 			.map_err(GarageError::from)?;
 
-		for res in tree.iter() {
+		for res in tree.iter().map_err(GarageError::from)? {
 			let (_k, v) = res.map_err(GarageError::from)?;
 			let bucket = rmp_serde::decode::from_read_ref::<_, old_bucket::Bucket>(&v[..])
 				.map_err(GarageError::from)?;
diff --git a/src/table/Cargo.toml b/src/table/Cargo.toml
index 6ae50366..6de37cda 100644
--- a/src/table/Cargo.toml
+++ b/src/table/Cargo.toml
@@ -26,8 +26,6 @@ hexdump = "0.1"
 tracing = "0.1.30"
 rand = "0.8"
 
-sled = "0.34"
-
 rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"
diff --git a/src/table/data.rs b/src/table/data.rs
index 5cb10066..ebfae551 100644
--- a/src/table/data.rs
+++ b/src/table/data.rs
@@ -3,12 +3,12 @@ use std::convert::TryInto;
 use std::sync::Arc;
 
 use serde_bytes::ByteBuf;
-use sled::{IVec, Transactional};
 use tokio::sync::Notify;
 
+use garage_db as db;
+
 use garage_util::data::*;
 use garage_util::error::*;
-use garage_util::sled_counter::SledCountedTree;
 
 use garage_rpc::system::System;
 
@@ -25,12 +25,12 @@ pub struct TableData<F: TableSchema, R: TableReplication> {
 	pub instance: F,
 	pub replication: R,
 
-	pub store: sled::Tree,
+	pub store: db::Tree,
 
-	pub(crate) merkle_tree: sled::Tree,
-	pub(crate) merkle_todo: sled::Tree,
+	pub(crate) merkle_tree: db::Tree,
+	pub(crate) merkle_todo: db::Tree,
 	pub(crate) merkle_todo_notify: Notify,
-	pub(crate) gc_todo: SledCountedTree,
+	pub(crate) gc_todo: db::Tree,
 
 	pub(crate) metrics: TableMetrics,
 }
@@ -40,7 +40,7 @@ where
 	F: TableSchema,
 	R: TableReplication,
 {
-	pub fn new(system: Arc<System>, instance: F, replication: R, db: &sled::Db) -> Arc<Self> {
+	pub fn new(system: Arc<System>, instance: F, replication: R, db: &db::Db) -> Arc<Self> {
 		let store = db
 			.open_tree(&format!("{}:table", F::TABLE_NAME))
 			.expect("Unable to open DB tree");
@@ -55,7 +55,6 @@ where
 		let gc_todo = db
 			.open_tree(&format!("{}:gc_todo_v2", F::TABLE_NAME))
 			.expect("Unable to open DB tree");
-		let gc_todo = SledCountedTree::new(gc_todo);
 
 		let metrics = TableMetrics::new(F::TABLE_NAME, merkle_todo.clone(), gc_todo.clone());
 
@@ -98,30 +97,30 @@ where
 					None => partition_hash.to_vec(),
 					Some(sk) => self.tree_key(partition_key, sk),
 				};
-				let range = self.store.range(first_key..);
+				let range = self.store.range(first_key..)?;
 				self.read_range_aux(partition_hash, range, filter, limit)
 			}
 			EnumerationOrder::Reverse => match start {
 				Some(sk) => {
 					let last_key = self.tree_key(partition_key, sk);
-					let range = self.store.range(..=last_key).rev();
+					let range = self.store.range_rev(..=last_key)?;
 					self.read_range_aux(partition_hash, range, filter, limit)
 				}
 				None => {
 					let mut last_key = partition_hash.to_vec();
 					let lower = u128::from_be_bytes(last_key[16..32].try_into().unwrap());
 					last_key[16..32].copy_from_slice(&u128::to_be_bytes(lower + 1));
-					let range = self.store.range(..last_key).rev();
+					let range = self.store.range_rev(..last_key)?;
 					self.read_range_aux(partition_hash, range, filter, limit)
 				}
 			},
 		}
 	}
 
-	fn read_range_aux(
+	fn read_range_aux<'a>(
 		&self,
 		partition_hash: Hash,
-		range: impl Iterator<Item = sled::Result<(IVec, IVec)>>,
+		range: db::ValueIter<'a>,
 		filter: &Option<F::Filter>,
 		limit: usize,
 	) -> Result<Vec<Arc<ByteBuf>>, Error> {
@@ -183,12 +182,10 @@ where
 		tree_key: &[u8],
 		f: impl Fn(Option<F::E>) -> F::E,
 	) -> Result<Option<F::E>, Error> {
-		let changed = (&self.store, &self.merkle_todo).transaction(|(store, mkl_todo)| {
-			let (old_entry, old_bytes, new_entry) = match store.get(tree_key)? {
+		let changed = self.store.db().transaction(|tx| {
+			let (old_entry, old_bytes, new_entry) = match tx.get(&self.store, tree_key)? {
 				Some(old_bytes) => {
-					let old_entry = self
-						.decode_entry(&old_bytes)
-						.map_err(sled::transaction::ConflictableTransactionError::Abort)?;
+					let old_entry = self.decode_entry(&old_bytes).map_err(db::TxError::Abort)?;
 					let new_entry = f(Some(old_entry.clone()));
 					(Some(old_entry), Some(old_bytes), new_entry)
 				}
@@ -204,13 +201,17 @@ where
 			// the associated Merkle tree entry.
 			let new_bytes = rmp_to_vec_all_named(&new_entry)
 				.map_err(Error::RmpEncode)
-				.map_err(sled::transaction::ConflictableTransactionError::Abort)?;
+				.map_err(db::TxError::Abort)?;
 			let encoding_changed = Some(&new_bytes[..]) != old_bytes.as_ref().map(|x| &x[..]);
 
 			if value_changed || encoding_changed {
 				let new_bytes_hash = blake2sum(&new_bytes[..]);
-				mkl_todo.insert(tree_key.to_vec(), new_bytes_hash.as_slice())?;
-				store.insert(tree_key.to_vec(), new_bytes)?;
+				tx.insert(
+					&self.merkle_todo,
+					tree_key.to_vec(),
+					new_bytes_hash.as_slice(),
+				)?;
+				tx.insert(&self.store, tree_key.to_vec(), new_bytes)?;
 				Ok(Some((old_entry, new_entry, new_bytes_hash)))
 			} else {
 				Ok(None)
@@ -244,11 +245,11 @@ where
 	}
 
 	pub(crate) fn delete_if_equal(self: &Arc<Self>, k: &[u8], v: &[u8]) -> Result<bool, Error> {
-		let removed = (&self.store, &self.merkle_todo).transaction(|(store, mkl_todo)| {
-			if let Some(cur_v) = store.get(k)? {
+		let removed = self.store.db().transaction(|tx| {
+			if let Some(cur_v) = tx.get(&self.store, k)? {
 				if cur_v == v {
-					store.remove(k)?;
-					mkl_todo.insert(k, vec![])?;
+					tx.remove(&self.store, k)?;
+					tx.insert(&self.merkle_todo, k, vec![])?;
 					return Ok(true);
 				}
 			}
@@ -270,12 +271,12 @@ where
 		k: &[u8],
 		vhash: Hash,
 	) -> Result<bool, Error> {
-		let removed = (&self.store, &self.merkle_todo).transaction(|(store, mkl_todo)| {
-			if let Some(cur_v) = store.get(k)? {
+		let removed = self.store.db().transaction(|tx| {
+			if let Some(cur_v) = tx.get(&self.store, k)? {
 				if blake2sum(&cur_v[..]) == vhash {
-					store.remove(k)?;
-					mkl_todo.insert(k, vec![])?;
-					return Ok(Some(cur_v));
+					tx.remove(&self.store, k)?;
+					tx.insert(&self.merkle_todo, k, vec![])?;
+					return Ok(Some(cur_v.into_owned()));
 				}
 			}
 			Ok(None)
@@ -316,6 +317,6 @@ where
 	}
 
 	pub fn gc_todo_len(&self) -> usize {
-		self.gc_todo.len()
+		self.gc_todo.len().unwrap() // TODO fix unwrap
 	}
 }
diff --git a/src/table/gc.rs b/src/table/gc.rs
index 2a05b6ae..04872a38 100644
--- a/src/table/gc.rs
+++ b/src/table/gc.rs
@@ -12,9 +12,10 @@ use futures::select;
 use futures_util::future::*;
 use tokio::sync::watch;
 
+use garage_db as db;
+
 use garage_util::data::*;
 use garage_util::error::*;
-use garage_util::sled_counter::SledCountedTree;
 use garage_util::time::*;
 
 use garage_rpc::system::System;
@@ -106,7 +107,7 @@ where
 		// List entries in the GC todo list
 		// These entries are put there when a tombstone is inserted in the table
 		// (see update_entry in data.rs)
-		for entry_kv in self.data.gc_todo.iter() {
+		for entry_kv in self.data.gc_todo.iter()? {
 			let (k, vhash) = entry_kv?;
 			let mut todo_entry = GcTodoEntry::parse(&k, &vhash);
 
@@ -353,17 +354,17 @@ impl GcTodoEntry {
 	}
 
 	/// Parses a GcTodoEntry from a (k, v) pair stored in the gc_todo tree
-	pub(crate) fn parse(sled_k: &[u8], sled_v: &[u8]) -> Self {
+	pub(crate) fn parse(db_k: &[u8], db_v: &[u8]) -> Self {
 		Self {
-			tombstone_timestamp: u64::from_be_bytes(sled_k[0..8].try_into().unwrap()),
-			key: sled_k[8..].to_vec(),
-			value_hash: Hash::try_from(sled_v).unwrap(),
+			tombstone_timestamp: u64::from_be_bytes(db_k[0..8].try_into().unwrap()),
+			key: db_k[8..].to_vec(),
+			value_hash: Hash::try_from(db_v).unwrap(),
 			value: None,
 		}
 	}
 
 	/// Saves the GcTodoEntry in the gc_todo tree
-	pub(crate) fn save(&self, gc_todo_tree: &SledCountedTree) -> Result<(), Error> {
+	pub(crate) fn save(&self, gc_todo_tree: &db::Tree) -> Result<(), Error> {
 		gc_todo_tree.insert(self.todo_table_key(), self.value_hash.as_slice())?;
 		Ok(())
 	}
@@ -373,12 +374,15 @@ impl GcTodoEntry {
 	/// This is usefull to remove a todo entry only under the condition
 	/// that it has not changed since the time it was read, i.e.
 	/// what we have to do is still the same
-	pub(crate) fn remove_if_equal(&self, gc_todo_tree: &SledCountedTree) -> Result<(), Error> {
-		let _ = gc_todo_tree.compare_and_swap::<_, _, Vec<u8>>(
-			&self.todo_table_key()[..],
-			Some(self.value_hash),
-			None,
-		)?;
+	pub(crate) fn remove_if_equal(&self, gc_todo_tree: &db::Tree) -> Result<(), Error> {
+		let key = self.todo_table_key();
+		gc_todo_tree.db().transaction(|tx| {
+			let old_val = tx.get(gc_todo_tree, &key)?;
+			if old_val == Some(self.value_hash.as_slice().into()) {
+				tx.remove(gc_todo_tree, &key)?;
+			}
+			tx.commit(())
+		})?;
 		Ok(())
 	}
 
diff --git a/src/table/merkle.rs b/src/table/merkle.rs
index 93bf7e47..4b0b44ce 100644
--- a/src/table/merkle.rs
+++ b/src/table/merkle.rs
@@ -4,11 +4,10 @@ use std::time::Duration;
 use futures::select;
 use futures_util::future::*;
 use serde::{Deserialize, Serialize};
-use sled::transaction::{
-	ConflictableTransactionError, ConflictableTransactionResult, TransactionalTree,
-};
 use tokio::sync::watch;
 
+use garage_db as db;
+
 use garage_util::background::BackgroundRunner;
 use garage_util::data::*;
 use garage_util::error::Error;
@@ -90,7 +89,8 @@ where
 
 	async fn updater_loop(self: Arc<Self>, mut must_exit: watch::Receiver<bool>) {
 		while !*must_exit.borrow() {
-			if let Some(x) = self.data.merkle_todo.iter().next() {
+			if let Some(x) = self.data.merkle_todo.iter().unwrap().next() {
+				// TODO unwrap to remove
 				match x {
 					Ok((key, valhash)) => {
 						if let Err(e) = self.update_item(&key[..], &valhash[..]) {
@@ -137,13 +137,18 @@ where
 		};
 		self.data
 			.merkle_tree
+			.db()
 			.transaction(|tx| self.update_item_rec(tx, k, &khash, &key, new_vhash))?;
 
-		let deleted = self
-			.data
-			.merkle_todo
-			.compare_and_swap::<_, _, Vec<u8>>(k, Some(vhash_by), None)?
-			.is_ok();
+		let deleted = self.data.merkle_todo.db().transaction(|tx| {
+			let old_val = tx.get(&self.data.merkle_todo, k)?;
+			if old_val == Some(vhash_by.into()) {
+				tx.remove(&self.data.merkle_todo, k)?;
+				tx.commit(true)
+			} else {
+				tx.commit(false)
+			}
+		})?;
 
 		if !deleted {
 			debug!(
@@ -157,12 +162,12 @@ where
 
 	fn update_item_rec(
 		&self,
-		tx: &TransactionalTree,
+		tx: db::Transaction<'_>,
 		k: &[u8],
 		khash: &Hash,
 		key: &MerkleNodeKey,
 		new_vhash: Option<Hash>,
-	) -> ConflictableTransactionResult<Option<Hash>, Error> {
+	) -> db::TxResult<Option<Hash>, Error> {
 		let i = key.prefix.len();
 
 		// Read node at current position (defined by the prefix stored in key)
@@ -203,7 +208,7 @@ where
 							}
 							MerkleNode::Intermediate(_) => Some(MerkleNode::Intermediate(children)),
 							x @ MerkleNode::Leaf(_, _) => {
-								tx.remove(key_sub.encode())?;
+								tx.remove(&self.data.merkle_tree, key_sub.encode())?;
 								Some(x)
 							}
 						}
@@ -283,28 +288,27 @@ where
 
 	fn read_node_txn(
 		&self,
-		tx: &TransactionalTree,
+		tx: db::Transaction<'_>,
 		k: &MerkleNodeKey,
-	) -> ConflictableTransactionResult<MerkleNode, Error> {
-		let ent = tx.get(k.encode())?;
-		MerkleNode::decode_opt(ent).map_err(ConflictableTransactionError::Abort)
+	) -> db::TxResult<MerkleNode, Error> {
+		let ent = tx.get(&self.data.merkle_tree, k.encode())?;
+		MerkleNode::decode_opt(ent).map_err(db::TxError::Abort)
 	}
 
 	fn put_node_txn(
 		&self,
-		tx: &TransactionalTree,
+		tx: db::Transaction<'_>,
 		k: &MerkleNodeKey,
 		v: &MerkleNode,
-	) -> ConflictableTransactionResult<Hash, Error> {
+	) -> db::TxResult<Hash, Error> {
 		trace!("Put Merkle node: {:?} => {:?}", k, v);
 		if *v == MerkleNode::Empty {
-			tx.remove(k.encode())?;
+			tx.remove(&self.data.merkle_tree, k.encode())?;
 			Ok(self.empty_node_hash)
 		} else {
-			let vby = rmp_to_vec_all_named(v)
-				.map_err(|e| ConflictableTransactionError::Abort(e.into()))?;
+			let vby = rmp_to_vec_all_named(v).map_err(|e| db::TxError::Abort(e.into()))?;
 			let rethash = blake2sum(&vby[..]);
-			tx.insert(k.encode(), vby)?;
+			tx.insert(&self.data.merkle_tree, k.encode(), vby)?;
 			Ok(rethash)
 		}
 	}
@@ -316,11 +320,11 @@ where
 	}
 
 	pub fn merkle_tree_len(&self) -> usize {
-		self.data.merkle_tree.len()
+		self.data.merkle_tree.len().unwrap() // TODO fix unwrap
 	}
 
 	pub fn todo_len(&self) -> usize {
-		self.data.merkle_todo.len()
+		self.data.merkle_todo.len().unwrap() // TODO fix unwrap
 	}
 }
 
@@ -347,7 +351,7 @@ impl MerkleNodeKey {
 }
 
 impl MerkleNode {
-	fn decode_opt(ent: Option<sled::IVec>) -> Result<Self, Error> {
+	fn decode_opt(ent: Option<db::Value<'_>>) -> Result<Self, Error> {
 		match ent {
 			None => Ok(MerkleNode::Empty),
 			Some(v) => Ok(rmp_serde::decode::from_read_ref::<_, MerkleNode>(&v[..])?),
diff --git a/src/table/metrics.rs b/src/table/metrics.rs
index 752a2a6d..3318de88 100644
--- a/src/table/metrics.rs
+++ b/src/table/metrics.rs
@@ -1,6 +1,6 @@
 use opentelemetry::{global, metrics::*, KeyValue};
 
-use garage_util::sled_counter::SledCountedTree;
+use garage_db as db;
 
 /// TableMetrics reference all counter used for metrics
 pub struct TableMetrics {
@@ -19,11 +19,7 @@ pub struct TableMetrics {
 	pub(crate) sync_items_received: Counter<u64>,
 }
 impl TableMetrics {
-	pub fn new(
-		table_name: &'static str,
-		merkle_todo: sled::Tree,
-		gc_todo: SledCountedTree,
-	) -> Self {
+	pub fn new(table_name: &'static str, merkle_todo: db::Tree, gc_todo: db::Tree) -> Self {
 		let meter = global::meter(table_name);
 		TableMetrics {
 			_merkle_todo_len: meter
@@ -31,7 +27,7 @@ impl TableMetrics {
 					"table.merkle_updater_todo_queue_length",
 					move |observer| {
 						observer.observe(
-							merkle_todo.len() as u64,
+							merkle_todo.len().unwrap() as u64, // TODO fix unwrap
 							&[KeyValue::new("table_name", table_name)],
 						)
 					},
@@ -43,7 +39,7 @@ impl TableMetrics {
 					"table.gc_todo_queue_length",
 					move |observer| {
 						observer.observe(
-							gc_todo.len() as u64,
+							gc_todo.len().unwrap() as u64, // TODO fix unwrap
 							&[KeyValue::new("table_name", table_name)],
 						)
 					},
diff --git a/src/table/sync.rs b/src/table/sync.rs
index 08069ad0..87dfd1d8 100644
--- a/src/table/sync.rs
+++ b/src/table/sync.rs
@@ -258,7 +258,7 @@ where
 		while !*must_exit.borrow() {
 			let mut items = Vec::new();
 
-			for item in self.data.store.range(begin.to_vec()..end.to_vec()) {
+			for item in self.data.store.range(begin.to_vec()..end.to_vec())? {
 				let (key, value) = item?;
 				items.push((key.to_vec(), Arc::new(ByteBuf::from(value.as_ref()))));
 
@@ -603,7 +603,8 @@ impl SyncTodo {
 			let retain = nodes.contains(&my_id);
 			if !retain {
 				// Check if we have some data to send, otherwise skip
-				if data.store.range(begin..end).next().is_none() {
+				if data.store.range(begin..end).unwrap().next().is_none() {
+					// TODO fix unwrap
 					continue;
 				}
 			}
diff --git a/src/table/table.rs b/src/table/table.rs
index 2a167604..3c211728 100644
--- a/src/table/table.rs
+++ b/src/table/table.rs
@@ -13,6 +13,8 @@ use opentelemetry::{
 	Context,
 };
 
+use garage_db as db;
+
 use garage_util::data::*;
 use garage_util::error::Error;
 use garage_util::metrics::RecordDuration;
@@ -69,7 +71,7 @@ where
 {
 	// =============== PUBLIC INTERFACE FUNCTIONS (new, insert, get, etc) ===============
 
-	pub fn new(instance: F, replication: R, system: Arc<System>, db: &sled::Db) -> Arc<Self> {
+	pub fn new(instance: F, replication: R, system: Arc<System>, db: &db::Db) -> Arc<Self> {
 		let endpoint = system
 			.netapp
 			.endpoint(format!("garage_table/table.rs/Rpc:{}", F::TABLE_NAME));
diff --git a/src/util/Cargo.toml b/src/util/Cargo.toml
index 95cde531..5d073436 100644
--- a/src/util/Cargo.toml
+++ b/src/util/Cargo.toml
@@ -14,6 +14,8 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+garage_db = { version = "0.8.0", path = "../db" }
+
 blake2 = "0.9"
 err-derive = "0.3"
 xxhash-rust = { version = "0.8", default-features = false, features = ["xxh3"] }
@@ -22,8 +24,6 @@ tracing = "0.1.30"
 rand = "0.8"
 sha2 = "0.9"
 
-sled = "0.34"
-
 chrono = "0.4"
 rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
diff --git a/src/util/error.rs b/src/util/error.rs
index 8734a0c8..9995c746 100644
--- a/src/util/error.rs
+++ b/src/util/error.rs
@@ -26,8 +26,8 @@ pub enum Error {
 	#[error(display = "Netapp error: {}", _0)]
 	Netapp(#[error(source)] netapp::error::Error),
 
-	#[error(display = "Sled error: {}", _0)]
-	Sled(#[error(source)] sled::Error),
+	#[error(display = "DB error: {}", _0)]
+	Db(#[error(source)] garage_db::Error),
 
 	#[error(display = "Messagepack encode error: {}", _0)]
 	RmpEncode(#[error(source)] rmp_serde::encode::Error),
@@ -78,11 +78,11 @@ impl Error {
 	}
 }
 
-impl From<sled::transaction::TransactionError<Error>> for Error {
-	fn from(e: sled::transaction::TransactionError<Error>) -> Error {
+impl From<garage_db::TxError<Error>> for Error {
+	fn from(e: garage_db::TxError<Error>) -> Error {
 		match e {
-			sled::transaction::TransactionError::Abort(x) => x,
-			sled::transaction::TransactionError::Storage(x) => Error::Sled(x),
+			garage_db::TxError::Abort(x) => x,
+			garage_db::TxError::Db(x) => Error::Db(x),
 		}
 	}
 }
diff --git a/src/util/lib.rs b/src/util/lib.rs
index d8ffdd0b..8ca6e310 100644
--- a/src/util/lib.rs
+++ b/src/util/lib.rs
@@ -11,7 +11,7 @@ pub mod error;
 pub mod formater;
 pub mod metrics;
 pub mod persister;
-pub mod sled_counter;
+//pub mod sled_counter;
 pub mod time;
 pub mod token_bucket;
 pub mod tranquilizer;