Best I can do to simplify the check(fmt::format)crap is to make a little macro to do the format part.

src/algos/stats.cpp

@@ -4,7 +4,7 @@
 
 void Stats::dump(std::string msg)
 {
-  dbc::log(fmt::format("{}: sum: {}, sumsq: {}, n: {}, "
+  dbc::log($F("{}: sum: {}, sumsq: {}, n: {}, "
             "min: {}, max: {}, mean: {}, stddev: {}",
             msg, sum, sumsq, n, min, max, mean(),
             stddev()));