NLog 4.5 adds structured logging and .NET Standard support/UPW without breaking changes!

RC 2 main features

List of important changes in NLog 4.5

Support for .Net Standard 1.5 #2341
Support for .Net Standard 2.0 #2263 + #2402
Support for UPW #2441
Introduced Structured logging #2208 + #2262 + #2244
Default file archive logic is now easier to use #1993
Introduced InstallationContext.ThrowExceptions #2214
WebServiceTarget can now batch multiple logevents into single request #2223
WebServiceTarget - Allow configuration of proxy address #2375
Json conversion also supports object properties #2179
event-properties layout-renderer can now render objects as json #2241
exception layout-renderer can now render exceptions as json #2357
${guid}, added GeneratedFromLogEvent #2226
TraceTarget RawWrite to always perform Trace.WriteLine independent of LogLevel #1968
Adding OverflowAction options to BufferingTargetWrapper #2276
WhenRepeatedFilter #2123 + #2297
${callsite} added CleanNamesOfAsyncContinuations option #2292
${ndlctiming} allows timing of ndlc-scopes #2377
NLogViewerTarget - Enable override of the Logger-name #2390
${sequenceid} added #2411
Added "regex-matches" for filtering #2437

Improve archive stability during concurrent file access #1889
FallbackGroup could lose log events #2265
Exception separator should only be inserted for available items #2250
${exception} - only include separator when items are available #2257
LogFactory - Fixes broken EventArgs for ConfigurationChanged #1897
Do not report wrapped targets as unused targets #2290
Added IIncludeContext, implemented missing properties #2117
Improve logging of callsite linenumber for async-methods #2386
NLogTraceListener - DisableFlush is enabled by default when AutoFlush=true #2407
NLogViewer - Better defaults for connection limits #2404
LoggingConfiguration.LoggingRules is not thread safe #2393, 2418

More targets has OptimizeBufferReuse enabled by default #1913 + #1923 + #1912 + #1911 + #1910 + #1909 + #1908 + #1907
StringBuilderPool - Improved Layout Render Performance by reusing StringBuilders #2208
JsonLayout - Improved Layout Performance, by optimizing use of StringBuilder #2208
FileTarget - Faster byte-encoding of log messsages, by using crude Encoding.GetMaxByteCount() instead of exact Encoding.GetByteCount() #2208
Target - Precalculate Layout should ignore sub-layouts for complex layout (Ex Json) #2378