Feat/same type auto map

[cloud-hai-vo]

Summary

Changes

Checklist

• Tests pass (dotnet test --configuration Release)
• No extra allocations introduced (if touching core mapping)
• Benchmarks checked (if touching performance-critical code)

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📊 Benchmark Results

Generated: 2026-03-27 14:03 UTC  ·  Download full artifacts

Column guide:
Mean = average execution time  ·  Error = half of 99.9 % confidence interval  ·  StdDev = standard deviation  ·  Min / Median / Max = statistical range  ·  Ratio = vs Manual baseline (lower = closer to hand-written speed)  ·  RatioSD = ratio std dev  ·  Rank = 1 is fastest  ·  Gen0/1/2 = GC collections per 1 000 ops  ·  Allocated = managed heap per operation  ·  Alloc Ratio = allocation ratio vs baseline

🔵 Flat Mapping — 10-property object

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Allocated	Alloc Ratio
Manual	14.86 ns	1.833 ns	0.100 ns	14.79 ns	14.82 ns	14.97 ns	1.00	0.01	1	0.0048	80 B	1.00
EggMapper	27.29 ns	2.347 ns	0.129 ns	27.20 ns	27.22 ns	27.44 ns	1.84	0.01	2	0.0048	80 B	1.00
AutoMapper	82.13 ns	2.269 ns	0.124 ns	82.01 ns	82.14 ns	82.26 ns	5.53	0.03	3	0.0048	80 B	1.00
Mapster	28.02 ns	1.092 ns	0.060 ns	27.96 ns	28.02 ns	28.08 ns	1.89	0.01	2	0.0048	80 B	1.00
MapperlyMap	14.71 ns	3.645 ns	0.200 ns	14.51 ns	14.70 ns	14.91 ns	0.99	0.01	1	0.0048	80 B	1.00
AgileMapper	494.61 ns	26.243 ns	1.438 ns	492.97 ns	495.21 ns	495.66 ns	33.29	0.21	4	0.0200	344 B	4.30
EggMapperGenerator	15.26 ns	2.716 ns	0.149 ns	15.11 ns	15.28 ns	15.41 ns	1.03	0.01	1	0.0048	80 B	1.00
EggMapperClassMapper	15.09 ns	0.924 ns	0.051 ns	15.04 ns	15.10 ns	15.14 ns	1.02	0.01	1	0.0048	80 B	1.00

🟡 Flattening — 2 nested objects → 8 flat properties

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Allocated	Alloc Ratio
Manual	18.82 ns	2.717 ns	0.149 ns	18.65 ns	18.91 ns	18.91 ns	1.00	0.01	1	0.0048	80 B	1.00
EggMap	29.98 ns	4.882 ns	0.268 ns	29.75 ns	29.93 ns	30.27 ns	1.59	0.02	3	0.0048	80 B	1.00
AutoMapper	95.79 ns	2.784 ns	0.153 ns	95.61 ns	95.87 ns	95.88 ns	5.09	0.04	4	0.0048	80 B	1.00
Mapster	35.85 ns	5.402 ns	0.296 ns	35.61 ns	35.75 ns	36.18 ns	1.90	0.02	3	0.0048	80 B	1.00
MapperlyMap	23.15 ns	4.359 ns	0.239 ns	22.91 ns	23.16 ns	23.39 ns	1.23	0.01	2	0.0062	104 B	1.30
AgileMapper	516.19 ns	70.530 ns	3.866 ns	512.31 ns	516.22 ns	520.04 ns	27.42	0.26	5	0.0200	344 B	4.30

🟣 Deep Mapping — 2 nested address objects

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Allocated	Alloc Ratio
Manual	52.94 ns	5.767 ns	0.316 ns	52.69 ns	52.83 ns	53.29 ns	1.00	0.01	1	0.0162	272 B	1.00
EggMapper	64.50 ns	33.049 ns	1.812 ns	63.07 ns	63.88 ns	66.53 ns	1.22	0.03	2	0.0162	272 B	1.00
AutoMapper	117.89 ns	12.291 ns	0.674 ns	117.13 ns	118.14 ns	118.40 ns	2.23	0.02	3	0.0162	272 B	1.00
Mapster	66.72 ns	9.688 ns	0.531 ns	66.11 ns	67.02 ns	67.03 ns	1.26	0.01	2	0.0162	272 B	1.00
MapperlyMap	49.53 ns	20.675 ns	1.133 ns	48.85 ns	48.90 ns	50.84 ns	0.94	0.02	1	0.0162	272 B	1.00
AgileMapper	510.89 ns	36.594 ns	2.006 ns	508.72 ns	511.27 ns	512.68 ns	9.65	0.06	4	0.0248	424 B	1.56

🟢 Complex Mapping — nested object + collection

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Allocated	Alloc Ratio
Manual	68.97 ns	9.998 ns	0.548 ns	68.34 ns	69.25 ns	69.32 ns	1.00	0.01	1	0.0191	320 B	1.00
EggMapper	90.01 ns	21.113 ns	1.157 ns	88.69 ns	90.54 ns	90.82 ns	1.31	0.02	2	0.0191	320 B	1.00
AutoMapper	159.11 ns	5.298 ns	0.290 ns	158.90 ns	158.98 ns	159.44 ns	2.31	0.02	3	0.0196	328 B	1.02
Mapster	86.93 ns	13.574 ns	0.744 ns	86.25 ns	86.80 ns	87.72 ns	1.26	0.01	2	0.0191	320 B	1.00
MapperlyMap	71.22 ns	11.361 ns	0.623 ns	70.50 ns	71.55 ns	71.60 ns	1.03	0.01	1	0.0191	320 B	1.00
AgileMapper	564.75 ns	52.900 ns	2.900 ns	562.62 ns	563.58 ns	568.05 ns	8.19	0.07	4	0.0315	528 B	1.65

🟠 Collection — 100-item List<T>

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Gen1	Allocated	Alloc Ratio
Manual	1.692 μs	0.4062 μs	0.0223 μs	1.671 μs	1.690 μs	1.716 μs	1.00	0.02	1	0.5283	0.0172	8.65 KB	1.00
EggMapper	1.786 μs	0.3209 μs	0.0176 μs	1.766 μs	1.791 μs	1.800 μs	1.06	0.01	1	0.5283	0.0172	8.65 KB	1.00
AutoMapper	2.475 μs	1.5995 μs	0.0877 μs	2.378 μs	2.496 μs	2.550 μs	1.46	0.05	2	0.6065	0.0191	9.95 KB	1.15
Mapster	1.771 μs	0.7654 μs	0.0420 μs	1.727 μs	1.777 μs	1.810 μs	1.05	0.02	1	0.5283	0.0172	8.65 KB	1.00
MapperlyMap	1.765 μs	0.2068 μs	0.0113 μs	1.755 μs	1.763 μs	1.777 μs	1.04	0.01	1	0.5283	0.0172	8.65 KB	1.00
AgileMapper	2.501 μs	0.3376 μs	0.0185 μs	2.485 μs	2.498 μs	2.521 μs	1.48	0.02	2	0.5417	0.0153	8.91 KB	1.03

🟠 Collection — 100-item List<T>

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Gen1	Allocated	Alloc Ratio
Manual	5.174 μs	0.1965 μs	0.0108 μs	5.164 μs	5.174 μs	5.185 μs	1.00	0.00	1	1.6708	0.0916	27.4 KB	1.00
EggMapper	5.657 μs	0.7458 μs	0.0409 μs	5.615 μs	5.659 μs	5.696 μs	1.09	0.01	1	1.6708	0.0916	27.4 KB	1.00
AutoMapper	6.517 μs	0.8210 μs	0.0450 μs	6.469 μs	6.524 μs	6.558 μs	1.26	0.01	1	1.7548	0.1068	28.7 KB	1.05
Mapster	5.770 μs	1.7767 μs	0.0974 μs	5.664 μs	5.788 μs	5.857 μs	1.12	0.02	1	1.6708	0.0916	27.4 KB	1.00
MapperlyMap	5.359 μs	1.4822 μs	0.0812 μs	5.279 μs	5.358 μs	5.441 μs	1.04	0.01	1	1.6785	0.0992	27.42 KB	1.00
AgileMapper	5.225 μs	0.8870 μs	0.0486 μs	5.190 μs	5.206 μs	5.281 μs	1.01	0.01	1	1.0223	0.0610	16.72 KB	0.61

🟠 Collection — 100-item List<T>

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Gen1	Allocated	Alloc Ratio
Manual	17.07 μs	12.899 μs	0.707 μs	16.41 μs	16.98 μs	17.81 μs	1.00	0.05	1	5.2490	1.3123	85.99 KB	1.00
EggMapper	17.15 μs	3.187 μs	0.175 μs	17.01 μs	17.10 μs	17.35 μs	1.01	0.04	1	5.2490	1.3123	85.99 KB	1.00
AutoMapper	21.74 μs	10.308 μs	0.565 μs	21.41 μs	21.42 μs	22.39 μs	1.28	0.05	1	5.7678	1.4343	94.34 KB	1.10
Mapster	17.55 μs	1.984 μs	0.109 μs	17.43 μs	17.56 μs	17.65 μs	1.03	0.04	1	5.2490	1.3123	85.99 KB	1.00
MapperlyMap	18.59 μs	6.689 μs	0.367 μs	18.27 μs	18.52 μs	18.99 μs	1.09	0.04	1	5.2490	1.2817	86.02 KB	1.00
AgileMapper	20.05 μs	2.982 μs	0.163 μs	19.88 μs	20.06 μs	20.21 μs	1.18	0.04	1	5.2795	1.3123	86.25 KB	1.00

⚪ Startup / Configuration time

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Gen1	Allocated	Alloc Ratio
EggMapperStartup	1,284.509 μs	2,022.2581 μs	110.8468 μs	1,160.353 μs	1,319.643 μs	1,373.532 μs	1.005	0.11	3	3.9063	1.9531	95.29 KB	1.00
AutoMapperStartup	395.170 μs	718.5274 μs	39.3849 μs	353.748 μs	399.621 μs	432.140 μs	0.309	0.04	2	5.8594	-	104.52 KB	1.10
MapsterStartup	2.497 μs	0.4115 μs	0.0226 μs	2.478 μs	2.490 μs	2.522 μs	0.002	0.00	1	0.7019	0.0267	11.51 KB	0.12

EggMapper.Benchmarks.ColdStartBenchmark-report-github

Method	Mean	Error	StdDev	Min	Median	Max	Ratio	RatioSD	Rank	Gen0	Gen1	Allocated	Alloc Ratio
EggMapper	1.319 ms	0.8678 ms	0.0476 ms	1.264 ms	1.344 ms	1.349 ms	1.00	0.04	1	5.8594	3.9063	95.8 KB	1.00
AutoMapper	4.037 ms	9.7928 ms	0.5368 ms	3.536 ms	3.970 ms	4.604 ms	3.06	0.37	2	15.6250	7.8125	309.85 KB	3.23
Mapster	4.318 ms	9.9590 ms	0.5459 ms	3.714 ms	4.461 ms	4.777 ms	3.28	0.37	2	39.0625	15.6250	757.88 KB	7.91

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📝 Notes

• Each benchmark class is decorated with [MemoryDiagnoser] and [RankColumn].
• The global config (see src/EggMapper.Benchmarks/Program.cs) adds Min, Median, and Max columns.
• Manual is the hand-written baseline (ratio = 1.00). A ratio < 1 means faster than manual.
• Benchmarks run on GitHub-hosted runners — absolute times may vary between runs; focus on Ratio for comparisons.
• To reproduce locally:

  cd src/EggMapper.Benchmarks
  dotnet run --configuration Release -- --filter '*'