diff --git a/src/dexorder/bin/finaldata.py b/src/dexorder/bin/finaldata.py
index a057de9..38f5bb6 100644
--- a/src/dexorder/bin/finaldata.py
+++ b/src/dexorder/bin/finaldata.py
@@ -46,7 +46,7 @@ def flush_callback():
     if latest_block.get().height - block.height <= 2*confirms:
         log.info(f'forward filling to present time')
         for addr, data in address_metadata.items():
-            if data['type'] == 'Pool':
+            if data['type'] == 'Pool' and data['exchange'] >= 0:
                 ohlcs.light_update_all(addr, from_timestamp(block.timestamp), None)
     log.info("flushing OHLC's")
     ohlcs.flush()
diff --git a/src/dexorder/contract/contract_proxy.py b/src/dexorder/contract/contract_proxy.py
index 1628bd1..18f9807 100644
--- a/src/dexorder/contract/contract_proxy.py
+++ b/src/dexorder/contract/contract_proxy.py
@@ -13,6 +13,7 @@ from dexorder.util import hexstr
 
 log = logging.getLogger(__name__)
 
+
 class ContractTransaction:
     def __init__(self, id_bytes: bytes, rawtx: Optional[bytes] = None):
         self.id_bytes = id_bytes
@@ -54,7 +55,7 @@ def call_wrapper(addr, name, func):
         try:
             return await func(*args, **kwargs).call(block_identifier=blockhash)
         except Web3Exception as e:
-            log.error(f"Exception calling {addr}.{name}()")
+            e.args += addr, name
             raise e
     return f
 
@@ -64,7 +65,7 @@ def transact_wrapper(addr, name, func):
         try:
             tx_id = await func(*args, **kwargs).transact()
         except Web3Exception as e:
-            log.error(f'Exception transacting {addr}.{name}()')
+            e.args += addr, name
             raise e
         return ContractTransaction(tx_id)
     return f
diff --git a/src/dexorder/database/model/pool.py b/src/dexorder/database/model/pool.py
index 58a98d1..fea0e75 100644
--- a/src/dexorder/database/model/pool.py
+++ b/src/dexorder/database/model/pool.py
@@ -19,8 +19,6 @@ class PoolDict (TypedDict):
     quote: str
     fee: int
     decimals: int
-    approved: bool  # whether this pool has only whitelisted tokens
-    liquidity: Optional[int]
 
 
 class Pool (Base):
diff --git a/src/dexorder/ohlc.py b/src/dexorder/ohlc.py
index 589cdf7..ec5023b 100644
--- a/src/dexorder/ohlc.py
+++ b/src/dexorder/ohlc.py
@@ -1,6 +1,5 @@
 import logging
 import os
-from collections import defaultdict
 from datetime import datetime, timedelta, timezone
 from decimal import InvalidOperation
 from typing import Optional, NamedTuple, Reversible, Union, TypedDict
@@ -401,16 +400,18 @@ class OHLCRepository:
         return found
 
     def flush(self) -> None:
+        log.debug(f'flushing {len(self.dirty_chunks)} chunks')
         for chunk in self.dirty_chunks:
             chunk.save()
         self.dirty_chunks.clear()
-        filepath = os.path.join(self.dir, quotes_path())
-        for _ in range(2):
-            try:
-                with open(filepath, 'w') as f:
-                    json.dump(self.quotes, f)
-            except FileNotFoundError:
-                os.makedirs(os.path.dirname(filepath), exist_ok=True)
+        if self._quotes:
+            filepath = os.path.join(self.dir, quotes_path())
+            for _ in range(2):
+                try:
+                    with open(filepath, 'w') as f:
+                        json.dump(self._quotes, f)
+                except FileNotFoundError:
+                    os.makedirs(os.path.dirname(filepath), exist_ok=True)
 
 
 class SeriesDict (TypedDict):
@@ -425,7 +426,7 @@ class FinalOHLCRepository (OHLCRepository):
         super().__init__(base_dir, chain_id=chain_id)
         self.current:dict[tuple[str,timedelta],NativeOHLC] = {}  # current bars keyed by symbol
         self.dirty_bars = set()
-        self.series:dict[int,dict[str,SeriesDict]] = defaultdict(dict)  # keyed by [chain_id][symbol]
+        self.series:dict[str,dict[str,SeriesDict]] = {}  # keyed by [str(chain_id)][symbol]
         self._series_dirty = False
 
     def light_update_all(self, symbol: str, time: datetime, price: Optional[dec]):
@@ -446,7 +447,7 @@ class FinalOHLCRepository (OHLCRepository):
             prev = self.current[key] = chunk.bar_at(start)
 #             log.debug(f'loaded prev bar from chunk {prev}')
         if prev is None and symbol in self.quotes:
-            latest_bar_time = ohlc_start_time(self.quotes[symbol][0], period)
+            latest_bar_time = ohlc_start_time(from_timestamp(self.quotes[symbol][0]), period)
             prev = self.current[key] = self.get_chunk(symbol, period, latest_bar_time).bar_at(latest_bar_time)
         if prev is None:
             # never seen before.  create new bar.
@@ -462,7 +463,10 @@ class FinalOHLCRepository (OHLCRepository):
             bar = self.current[key] = NativeOHLC(start, price, price, price, close)
             chunk.update(bar, backfill=backfill)
             self.dirty_chunks.add(chunk)
-            self.series[current_chain.get().chain_id][f'{key[0]}|{key[1]}'] = {'start': timestamp(start)}
+            chain_id_str = str(current_chain.get().chain_id)
+            if chain_id_str not in self.series:
+                self.series[chain_id_str] = {}
+            self.series[chain_id_str][f'{key[0]}|{key[1]}'] = {'start': timestamp(start)}
             self._series_dirty = True
         else:
             updated = update_ohlc(prev, period, time, price)
diff --git a/src/dexorder/pools.py b/src/dexorder/pools.py
index 1e274d5..c918c2b 100644
--- a/src/dexorder/pools.py
+++ b/src/dexorder/pools.py
@@ -14,7 +14,7 @@ from dexorder.blockstate import BlockDict
 from dexorder.blockstate.blockdata import K, V
 from dexorder.blocktime import get_block_timestamp
 from dexorder.database.model.pool import PoolDict
-from dexorder.metadata import generating_metadata, is_generating_metadata
+from dexorder.metadata import is_generating_metadata
 from dexorder.tokens import get_token
 from dexorder.uniswap import UniswapV3Pool, uniswapV3_pool_address
 
@@ -44,7 +44,7 @@ async def load_pool(address: str) -> PoolDict:
                 decimals = token0['decimals'] - token1['decimals']
                 found = PoolDict(type='Pool', chain=chain_id, address=address, exchange=Exchange.UniswapV3.value,
                                  base=t0, quote=t1, fee=fee, decimals=decimals)
-                log.debug(f'new UniswapV3 pool {token0["symbol"]}\\{token1["symbol"]} '
+                log.debug(f'new UniswapV3 pool {token0["symbol"]}/{token1["symbol"]} '
                           f'{("."+str(decimals)) if decimals >= 0 else (str(-decimals)+".")} {address}')
     except ContractLogicError:
         pass
diff --git a/src/dexorder/runner.py b/src/dexorder/runner.py
index 04759b6..656f233 100644
--- a/src/dexorder/runner.py
+++ b/src/dexorder/runner.py
@@ -80,7 +80,8 @@ class BlockStateRunner(BlockProgressor):
         self.timer_period = timer_period
 
         self.queue: Queue = Queue()
-        self.max_height_seen = config.backfill
+        self.max_height_seen = config.backfill if config.backfill is None or config.backfill >= 0 \
+            else current_block.get().height + config.backfill  # if backfill is negative then it's relative to the current block
 
         self.running = False
 
diff --git a/src/dexorder/tokens.py b/src/dexorder/tokens.py
index f00e6dd..66c7278 100644
--- a/src/dexorder/tokens.py
+++ b/src/dexorder/tokens.py
@@ -5,7 +5,7 @@ from typing import Optional
 from eth_abi.exceptions import InsufficientDataBytes
 from web3.exceptions import ContractLogicError, BadFunctionCallOutput
 
-from dexorder import ADDRESS_0
+from dexorder import ADDRESS_0, config
 from dexorder.addrmeta import address_metadata
 from dexorder.base.chain import current_chain
 from dexorder.contract import ERC20, ContractProxy
@@ -48,7 +48,7 @@ async def load_token(address: str) -> Optional[TokenDict]:
     log.debug(f'new token {name} {symbol} {address}')
     chain_id = current_chain.get().chain_id
     td = TokenDict(type='Token', chain=chain_id, address=address,
-                   name=name, symbol=symbol, decimals=decimals, approved=False)
+                   name=name, symbol=symbol, decimals=decimals, approved=config.metadata is None)
     md = get_metadata(address, chain_id=chain_id)
     if md is not None:
         td['approved'] = True
diff --git a/src/dexorder/util/json.py b/src/dexorder/util/json.py
index fccfbdc..efa709b 100644
--- a/src/dexorder/util/json.py
+++ b/src/dexorder/util/json.py
@@ -1,3 +1,4 @@
+from collections import defaultdict
 from decimal import Decimal
 from json import JSONEncoder
 from typing import Any
@@ -10,13 +11,14 @@ from dexorder import DELETE
 
 
 def _serialize(v):
-    if type(v) is HexBytes:
+    t = type(v)
+    if t is HexBytes:
         return v.hex()
-    elif type(v) is bytes:
+    elif t is bytes:
         return '0x' + v.hex()
-    elif type(v) is AttributeDict:
+    elif t is AttributeDict:
         return v.__dict__
-    elif type(v) is Decimal:
+    elif t is Decimal:
         return f'{v:f}'
     elif v is DELETE:
         return None
diff --git a/src/dexorder/walker.py b/src/dexorder/walker.py
index ea296ec..dbcd918 100644
--- a/src/dexorder/walker.py
+++ b/src/dexorder/walker.py
@@ -51,7 +51,14 @@ class BlockWalker (BlockProgressor):
 
         kv_key = f'walker_height|{chain_id}'
         with db.session:
-            processed_height = db.kv.get(kv_key, config.backfill)
+            processed_height = db.kv.get(kv_key)
+            if processed_height is None:
+                if config.backfill > 0:
+                    processed_height = config.backfill
+                else:
+                    cur = await w3.eth.get_block_number()
+                    processed_height = cur + config.backfill if config.backfill < 0 else cur
+
         log.info(f'walker starting at block {processed_height}')
         last_flush = processed_height if self.flush_type == 'blocks' else now() if self.flush_type == 'time' else None
         prev_height = None