Original query:

tickers=# WITH s as (SELECT symbol from symbols WHERE symbol in ('BTC', 'ETH'))
tickers-# SELECT s.symbol, l.closing_price,  (SELECT closing_price from tickers t WHERE time > now()-interval '1 month' AND t.symbol = s.symbol ORDER BY time asc LIMIT 1) AS opening, l.change_1H, l.change_7D, l.change_1M, l.change_1Y, m.max as high, m.min as low
tickers-# FROM s, lateral (SELECT * FROM tickers t  WHERE t.symbol = s.symbol and time > now()-interval '1 month' LIMIT 1) as l, lateral (SELECT max(closing_price), min(closing_price) FROM tickers t WHERE t.symbol = s.symbol and time > now()-interval '1 month') as m;
 symbol |  closing_price   |     opening      | change_1h |     change_7d     |     change_1m     |     change_1y     |       high       |       low
--------+------------------+------------------+-----------+-------------------+-------------------+-------------------+------------------+------------------
 BTC    | 3421.45051554496 | 26197.6296049351 |         0 | -2.27776511685668 | -4.70582288205846 | -5.79968183345321 | 26201.6679026798 | 1024.75738257235
 ETH    | 173.919827122068 | 164.893832315301 |         0 | -1.99935361170152 | -2.04294294553663 | 0.277574242083482 | 190.739797744465 | 120.160005175588
(2 rows)