diff --git a/Cargo.toml b/Cargo.toml
index 1d20018..41ddf87 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,8 +4,9 @@ members = [
   "hftbacktest",
   "hftbacktest-derive",
   "py-hftbacktest",
-  "collector"
-, "connector"]
+  "collector", 
+  "connector",
+  "contrib/converter"]
 
 [profile.dev]
 opt-level = 0
diff --git a/contrib/converter/Cargo.toml b/contrib/converter/Cargo.toml
new file mode 100644
index 0000000..15342a9
--- /dev/null
+++ b/contrib/converter/Cargo.toml
@@ -0,0 +1,13 @@
+[package]
+name = "converter"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+zip = { version = "2.1.3" }
+flate2 = {version = "1.0.34" }
+hftbacktest = { path = "../../hftbacktest" }
+hftbacktest-derive = { path = "../../hftbacktest-derive" }
+serde = { version = "1.0.210", features = ["derive"] }
+serde_json = "1.0.128"
+clap = { version = "4.5.17", features = ["derive"] }
diff --git a/contrib/converter/src/bybit.rs b/contrib/converter/src/bybit.rs
new file mode 100644
index 0000000..8ef3f37
--- /dev/null
+++ b/contrib/converter/src/bybit.rs
@@ -0,0 +1,177 @@
+use crate::converter::ConverterBase;
+
+use hftbacktest::types::Event;
+use hftbacktest::types::{
+    BUY_EVENT, DEPTH_CLEAR_EVENT, DEPTH_EVENT, DEPTH_SNAPSHOT_EVENT, SELL_EVENT, TRADE_EVENT,
+};
+use serde_json::Value;
+
+use serde::de::Error;
+use serde::{Deserialize, Deserializer};
+
+// Everything we do below is based on the bybit API which is covered in detail
+// at https://bybit-exchange.github.io/docs/v5/websocket/public/orderbook.
+
+// This is almost a carbon copy of the structs used in the bybit connector. In an ideal
+// world they would be moved into the main rust lib and then reused here.
+
+fn from_str_to_f64<'de, D: Deserializer<'de>>(deserializer: D) -> Result<f64, D::Error> {
+    Ok(match Value::deserialize(deserializer)? {
+        Value::String(s) => s.parse().map_err(Error::custom)?,
+        Value::Number(num) => num
+            .as_f64()
+            .ok_or_else(|| Error::custom("Invalid number"))?,
+        _ => return Err(Error::custom("wrong type")),
+    })
+}
+
+#[derive(Deserialize, Debug)]
+pub struct PublicStream {
+    pub topic: String,
+    #[serde(rename = "type")]
+    pub event_type: String,
+    pub data: Value,
+    pub cts: Option<i64>,
+}
+
+#[derive(Deserialize, Debug)]
+pub struct OrderBook {
+    #[serde(rename = "b")]
+    pub bids: Vec<(String, String)>,
+    #[serde(rename = "a")]
+    pub asks: Vec<(String, String)>,
+}
+
+#[derive(Deserialize, Debug)]
+pub struct Trade {
+    #[serde(rename = "T")]
+    pub ts: i64,
+    #[serde(rename = "S")]
+    pub side: String,
+    #[serde(rename = "v")]
+    #[serde(deserialize_with = "from_str_to_f64")]
+    pub trade_size: f64,
+    #[serde(rename = "p")]
+    #[serde(deserialize_with = "from_str_to_f64")]
+    pub trade_price: f64,
+}
+
+pub fn bybit_process(
+    base: &mut ConverterBase,
+    local_ts: i64,
+    payload: &str,
+) -> Result<Vec<Event>, Box<dyn std::error::Error>> {
+    let mut result: Vec<Event> = Vec::new();
+
+    let stream = serde_json::from_str::<PublicStream>(payload)?;
+
+    if stream.topic.starts_with("publicTrade") {
+        let trades: Vec<Trade> = serde_json::from_value(stream.data)?;
+        for trade in trades {
+            // adjust if necessary and detect negative latency..
+            let mut exch_ts = base.convert_ts(trade.ts);
+            let latency = local_ts - exch_ts;
+            exch_ts = local_ts + base.latency(latency);
+
+            let event_type = match &*trade.side {
+                "Sell" => TRADE_EVENT | SELL_EVENT,
+                "Buy" => TRADE_EVENT | BUY_EVENT,
+                _ => TRADE_EVENT | SELL_EVENT, // Assume mm trade..
+            };
+
+            result.push(Event {
+                ev: event_type,
+                exch_ts,
+                local_ts,
+                order_id: 0,
+                px: trade.trade_price,
+                qty: trade.trade_size,
+                ival: 0,
+                fval: 0.0,
+            })
+        }
+    } else if stream.topic.starts_with("orderbook") {
+        // adjust if necessary and detect negative latency..
+        let mut exch_ts = base.convert_ts(stream.cts.ok_or("Missing CTS on order book event")?);
+        let latency = local_ts - exch_ts;
+        exch_ts = local_ts + base.latency(latency);
+
+        let order_book: OrderBook = serde_json::from_value(stream.data)?;
+
+        if order_book.asks.len() > 0 {
+            let (last_ask_px_str, _) = order_book.asks.last().unwrap();
+
+            let ev = match &*stream.event_type {
+                "snapshot" => DEPTH_SNAPSHOT_EVENT | SELL_EVENT,
+                _ => DEPTH_EVENT | SELL_EVENT,
+            };
+
+            // Clear the books if this is a snapshot..
+            if stream.event_type == "snapshot" {
+                result.push(Event {
+                    ev: DEPTH_CLEAR_EVENT | SELL_EVENT,
+                    exch_ts,
+                    local_ts,
+                    order_id: 0,
+                    px: last_ask_px_str.parse::<f64>()?,
+                    qty: 0.0,
+                    ival: 0,
+                    fval: 0.0,
+                })
+            }
+
+            // Insert entries..
+            for (ask_px, ask_qty) in order_book.asks {
+                result.push(Event {
+                    ev,
+                    exch_ts,
+                    local_ts,
+                    order_id: 0,
+                    px: ask_px.parse::<f64>()?,
+                    qty: ask_qty.parse::<f64>()?,
+                    ival: 0,
+                    fval: 0.0,
+                })
+            }
+        }
+
+        if order_book.bids.len() > 0 {
+            let (last_bid_px_str, _) = order_book.bids.last().unwrap();
+
+            let ev = match &*stream.event_type {
+                "snapshot" => DEPTH_SNAPSHOT_EVENT | BUY_EVENT,
+                _ => DEPTH_EVENT | BUY_EVENT,
+            };
+
+            // Clear the books if this is a snapshot..
+            if stream.event_type == "snapshot" {
+                result.push(Event {
+                    ev: DEPTH_CLEAR_EVENT | BUY_EVENT,
+                    exch_ts,
+                    local_ts,
+                    order_id: 0,
+                    px: last_bid_px_str.parse::<f64>()?,
+                    qty: 0.0,
+                    ival: 0,
+                    fval: 0.0,
+                })
+            }
+
+            // Insert entries..
+            for (bid_px, bid_qty) in order_book.bids {
+                result.push(Event {
+                    ev,
+                    exch_ts,
+                    local_ts,
+                    order_id: 0,
+                    px: bid_px.parse::<f64>()?,
+                    qty: bid_qty.parse::<f64>()?,
+                    ival: 0,
+                    fval: 0.0,
+                })
+            }
+        }
+    }
+
+    Ok(result)
+}
diff --git a/contrib/converter/src/converter.rs b/contrib/converter/src/converter.rs
new file mode 100644
index 0000000..0b5988d
--- /dev/null
+++ b/contrib/converter/src/converter.rs
@@ -0,0 +1,98 @@
+use flate2::read::GzDecoder;
+use hftbacktest::types::Event;
+use std::fs::File;
+use std::io::{BufRead, BufReader, BufWriter};
+
+use hftbacktest::backtest::data::write_npy_data;
+
+use crate::bybit::bybit_process;
+
+pub struct ConverterBase {
+    base_latency: i64,
+    min_latency: i64,
+    time_mul: i64,
+}
+
+impl ConverterBase {
+    pub fn new(base_latency: i64) -> Self {
+        Self {
+            base_latency,
+            min_latency: i64::MAX,
+            time_mul: 1_000_000, // convert to nanos.
+        }
+    }
+
+    pub fn convert_ts(&self, ts: i64) -> i64 {
+        ts * self.time_mul
+    }
+
+    pub fn latency(&mut self, latency: i64) -> i64 {
+        if latency > 0 && latency < self.min_latency {
+            self.min_latency = latency;
+        }
+
+        if latency < 0 {
+            return self.min_latency + self.base_latency;
+        }
+
+        latency
+    }
+}
+
+#[allow(non_camel_case_types)]
+pub enum Converter {
+    bybit(ConverterBase),
+}
+
+pub trait IConverter {
+    fn process(
+        &mut self,
+        local_ts: i64,
+        payload: &str,
+    ) -> Result<Vec<Event>, Box<dyn std::error::Error>>;
+}
+
+impl IConverter for Converter {
+    fn process(
+        &mut self,
+        local_ts: i64,
+        payload: &str,
+    ) -> Result<Vec<Event>, Box<dyn std::error::Error>> {
+        match self {
+            Converter::bybit(base) => bybit_process(base, local_ts, payload),
+        }
+    }
+}
+
+impl Converter {
+    pub fn new(exchange: &str, base_latency: i64) -> Self {
+        match exchange {
+            "bybit" => Converter::bybit(ConverterBase::new(base_latency)),
+            _ => panic!("Unknown exchange"),
+        }
+    }
+
+    pub fn process_file(
+        &mut self,
+        input: BufReader<GzDecoder<File>>,
+        output: &mut BufWriter<File>,
+    ) -> Result<usize, Box<dyn std::error::Error>> {
+        let mut counter: usize = 0;
+        for line in input.lines() {
+            let line = line?;
+
+            // Split the line into timestamp and JSON part
+            if let Some((timestamp_str, json_str)) = line.split_once(' ') {
+                // Parse the timestamp
+                let timestamp: i64 = timestamp_str.parse()?;
+                let events = self.process(timestamp, json_str)?;
+                counter += events.len();
+                write_npy_data(output, events.as_slice())?;
+            } else {
+                eprintln!("Error: line format incorrect: {}", line);
+            }
+        }
+
+        Ok(counter)
+    }
+}
diff --git a/contrib/converter/src/main.rs b/contrib/converter/src/main.rs
new file mode 100644
index 0000000..da70e5f
--- /dev/null
+++ b/contrib/converter/src/main.rs
@@ -0,0 +1,80 @@
+use flate2::read::GzDecoder;
+use hftbacktest::backtest::data::write_npy_header;
+use hftbacktest::types::Event;
+use std::fs::{remove_file, File};
+use std::io::{copy, BufReader, BufWriter, Seek, SeekFrom, Write};
+use zip::write::SimpleFileOptions;
+use zip::ZipWriter;
+
+use clap::Parser;
+
+mod bybit;
+mod converter;
+
+use converter::Converter;
+
+#[derive(Parser, Debug, Clone)]
+#[command(version, about, long_about = None)]
+struct Args {
+    #[arg(long)]
+    exchange: String,
+
+    #[arg(long)]
+    input: String,
+
+    #[arg(long, default_value = "test.npz")]
+    output: String,
+
+    #[arg(long, default_value_t = 5_000_000)]
+    base_latency: i64,
+
+    #[arg(long, default_value = "/tmp/")]
+    temp_dir: String,
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let args = Args::parse();
+
+    let mut temp_file = args.temp_dir;
+    temp_file.push_str("temp.npy");
+    let file = File::create(&temp_file)?;
+    let mut writer = BufWriter::new(file);
+
+    // This ordering may not be optimal for speed!
+    let input = File::open(args.input.clone())?;
+    let decoder = GzDecoder::new(input);
+    let reader = BufReader::new(decoder);
+
+    let mut converter = Converter::new(&*args.exchange, args.base_latency);
+
+    write_npy_header::<BufWriter<File>, Event>(&mut writer, 0)?;
+
+    // Actually do the work..
+    println!("Converting {} to {}", args.input, &temp_file);
+    let counter = converter.process_file(reader, &mut writer)?;
+    println!("Created {} events", counter);
+
+    writer.seek(SeekFrom::Start(0))?;
+    write_npy_header::<BufWriter<File>, Event>(&mut writer, counter)?;
+    writer.flush()?;
+
+    let output = File::create(&args.output)?;
+    let zip_writer = BufWriter::new(output);
+    let mut zip = ZipWriter::new(zip_writer);
+
+    let options = SimpleFileOptions::default()
+        .compression_method(zip::CompressionMethod::DEFLATE)
+        .compression_level(Some(9));
+
+    zip.start_file("data.npy", options)?;
+
+    println!("Compressing {} to {}", &temp_file, &args.output);
+    let mut temp_read = BufReader::new(File::open(&temp_file)?);
+    copy(&mut temp_read, &mut zip)?;
+    zip.finish()?;
+
+    println!("Removing {}", &temp_file);
+    remove_file(&temp_file)?;
+
+    Ok(())
+}
diff --git a/hftbacktest/src/backtest/data/mod.rs b/hftbacktest/src/backtest/data/mod.rs
index 311cd1e..ca1b7a2 100644
--- a/hftbacktest/src/backtest/data/mod.rs
+++ b/hftbacktest/src/backtest/data/mod.rs
@@ -10,7 +10,10 @@ use std::{
     slice::SliceIndex,
 };
 
-pub use npy::{read_npy_file, read_npz_file, write_npy, Field, NpyDTyped, NpyHeader};
+pub use npy::{
+    read_npy_file, read_npz_file, write_npy, write_npy_data, write_npy_header, Field, NpyDTyped,
+    NpyHeader,
+};
 pub use reader::{Cache, DataPreprocess, DataSource, FeedLatencyAdjustment, Reader, ReaderBuilder};
 
 use crate::utils::{AlignedArray, CACHE_LINE_SIZE};
diff --git a/hftbacktest/src/backtest/data/npy/mod.rs b/hftbacktest/src/backtest/data/npy/mod.rs
index 41d35c1..6e0882a 100644
--- a/hftbacktest/src/backtest/data/npy/mod.rs
+++ b/hftbacktest/src/backtest/data/npy/mod.rs
@@ -248,6 +248,28 @@ pub fn read_npz_file<D: NpyDTyped + Clone>(filepath: &str, name: &str) -> std::i
     read_npy(&mut file, size)
 }
 
+pub fn write_npy_header<W: Write, T: NpyDTyped>(write: &mut W, len: usize) -> std::io::Result<()> {
+    let descr = T::descr();
+    let header = NpyHeader {
+        descr,
+        fortran_order: false,
+        shape: vec![len],
+    };
+
+    write.write_all(b"\x93NUMPY\x01\x00")?;
+    let header_str = header.to_string_padding();
+    let len = header_str.len() as u16;
+    write.write_all(&len.to_le_bytes())?;
+    write.write_all(header_str.as_bytes())?;
+
+    Ok(())
+}
+
+pub fn write_npy_data<W: Write, T: NpyDTyped>(write: &mut W, data: &[T]) -> std::io::Result<()> {
+    write.write_all(vec_as_bytes(data))?;
+    Ok(())
+}
+
 pub fn write_npy<W: Write, T: NpyDTyped>(write: &mut W, data: &[T]) -> std::io::Result<()> {
     let descr = T::descr();
     let header = NpyHeader {