CalcNetProfit (helpers.go) has internal price-swap logic — when
price2 < price1 it swaps buy/sell sides. ScanArbWithFees relies
on netProfit being a pure strict-direction calculation (callers
try both directions via addPair). Delegation caused double-swap:
both netProfit calls in addPair returned positive profit, but
direction1's struct reported wrong exchange pair, leading to
potential loss-making trades.
Keep both formulas as independent implementations with explicit
comments warning against future merging attempts.
B#1 — sigCh shared across goroutines, SIGINT unreliable
→ context.WithCancel: main loop cancels ctx on SIGINT,
4 WS goroutines select on ctx.Done() instead of shared sigCh
B#3 — restoreOpenPositions missing LastScaleAt
→ Set LastScaleAt = tr.OpenedAt on restore so scale-in cooldown works
B#4 — dYdX heartbeat goroutine leaks on reconnect
→ Added stopHeartbeat chan + heartbeatMu mutex; close old channel
before spawning new heartbeat goroutine
B#5 — GetBitgetSize fmt.Sprintf rounds up, may exceed amountUSD
→ Added math.Floor(sz*multiplier)/multiplier before format to round
DOWN to nearest valid step size for every coin
B#6 — netProfit and CalcNetProfit duplicate formula
→ scanner.go netProfit now delegates to exchange.CalcNetProfit
B#7 — Aevo Run callback only 2 params, incompatible with startExchange
→ Changed to 4-arg callback func(coin, price, bid, ask) with bid=ask=0
B#8 — parseFloat uses fmt.Sscanf (slow, locale-sensitive)
→ Replaced with strconv.ParseFloat
B#9 — dYdX receives hlSymbols instead of its own symbol list
→ Added dydxSymbols var, built from c.HL like other exchanges
jackyu66git