--- /dev/null
+# strftime
+
+Fast strftime for Go
+
+[](https://travis-ci.org/lestrrat-go/strftime)
+
+[](https://godoc.org/github.com/lestrrat-go/strftime)
+
+# SYNOPSIS
+
+```go
+f := strftime.New(`.... pattern ...`)
+if err := f.Format(buf, time.Now()); err != nil {
+ log.Println(err.Error())
+}
+```
+
+# DESCRIPTION
+
+The goals for this library are
+
+* Optimized for the same pattern being called repeatedly
+* Be flexible about destination to write the results out
+* Be as complete as possible in terms of conversion specifications
+
+# API
+
+## Format(string, time.Time) (string, error)
+
+Takes the pattern and the time, and formats it. This function is a utility function that recompiles the pattern every time the function is called. If you know beforehand that you will be formatting the same pattern multiple times, consider using `New` to create a `Strftime` object and reuse it.
+
+## New(string) (\*Strftime, error)
+
+Takes the pattern and creates a new `Strftime` object.
+
+## obj.Pattern() string
+
+Returns the pattern string used to create this `Strftime` object
+
+## obj.Format(io.Writer, time.Time) error
+
+Formats the time according to the pre-compiled pattern, and writes the result to the specified `io.Writer`
+
+## obj.FormatString(time.Time) string
+
+Formats the time according to the pre-compiled pattern, and returns the result string.
+
+# SUPPORTED CONVERSION SPECIFICATIONS
+
+| pattern | description |
+|:--------|:------------|
+| %A | national representation of the full weekday name |
+| %a | national representation of the abbreviated weekday |
+| %B | national representation of the full month name |
+| %b | national representation of the abbreviated month name |
+| %C | (year / 100) as decimal number; single digits are preceded by a zero |
+| %c | national representation of time and date |
+| %D | equivalent to %m/%d/%y |
+| %d | day of the month as a decimal number (01-31) |
+| %e | the day of the month as a decimal number (1-31); single digits are preceded by a blank |
+| %F | equivalent to %Y-%m-%d |
+| %H | the hour (24-hour clock) as a decimal number (00-23) |
+| %h | same as %b |
+| %I | the hour (12-hour clock) as a decimal number (01-12) |
+| %j | the day of the year as a decimal number (001-366) |
+| %k | the hour (24-hour clock) as a decimal number (0-23); single digits are preceded by a blank |
+| %l | the hour (12-hour clock) as a decimal number (1-12); single digits are preceded by a blank |
+| %M | the minute as a decimal number (00-59) |
+| %m | the month as a decimal number (01-12) |
+| %n | a newline |
+| %p | national representation of either "ante meridiem" (a.m.) or "post meridiem" (p.m.) as appropriate. |
+| %R | equivalent to %H:%M |
+| %r | equivalent to %I:%M:%S %p |
+| %S | the second as a decimal number (00-60) |
+| %T | equivalent to %H:%M:%S |
+| %t | a tab |
+| %U | the week number of the year (Sunday as the first day of the week) as a decimal number (00-53) |
+| %u | the weekday (Monday as the first day of the week) as a decimal number (1-7) |
+| %V | the week number of the year (Monday as the first day of the week) as a decimal number (01-53) |
+| %v | equivalent to %e-%b-%Y |
+| %W | the week number of the year (Monday as the first day of the week) as a decimal number (00-53) |
+| %w | the weekday (Sunday as the first day of the week) as a decimal number (0-6) |
+| %X | national representation of the time |
+| %x | national representation of the date |
+| %Y | the year with century as a decimal number |
+| %y | the year without century as a decimal number (00-99) |
+| %Z | the time zone name |
+| %z | the time zone offset from UTC |
+| %% | a '%' |
+
+# PERFORMANCE / OTHER LIBRARIES
+
+The following benchmarks were run separately because some libraries were using cgo on specific platforms (notabley, the fastly version)
+
+```
+// On my OS X 10.11.6, 2.9 GHz Intel Core i5, 16GB memory.
+// go version go1.8rc1 darwin/amd64
+hummingbird% go test -tags bench -benchmem -bench .
+<snip>
+BenchmarkTebeka-4 300000 4469 ns/op 288 B/op 21 allocs/op
+BenchmarkJehiah-4 1000000 1931 ns/op 256 B/op 17 allocs/op
+BenchmarkFastly-4 2000000 724 ns/op 80 B/op 5 allocs/op
+BenchmarkLestrrat-4 1000000 1572 ns/op 240 B/op 3 allocs/op
+BenchmarkLestrratCachedString-4 3000000 548 ns/op 128 B/op 2 allocs/op
+BenchmarkLestrratCachedWriter-4 500000 2519 ns/op 192 B/op 3 allocs/op
+PASS
+ok github.com/lestrrat-go/strftime 22.900s
+```
+
+```
+// On a host on Google Cloud Platform, machine-type: n1-standard-4 (vCPU x 4, memory: 15GB)
+// Linux <snip> 3.16.0-4-amd64 #1 SMP Debian 3.16.36-1+deb8u2 (2016-10-19) x86_64 GNU/Linux
+// go version go1.8rc1 linux/amd64
+hummingbird% go test -tags bench -benchmem -bench .
+<snip>
+BenchmarkTebeka-4 500000 3904 ns/op 288 B/op 21 allocs/op
+BenchmarkJehiah-4 1000000 1665 ns/op 256 B/op 17 allocs/op
+BenchmarkFastly-4 1000000 2134 ns/op 192 B/op 13 allocs/op
+BenchmarkLestrrat-4 1000000 1327 ns/op 240 B/op 3 allocs/op
+BenchmarkLestrratCachedString-4 3000000 498 ns/op 128 B/op 2 allocs/op
+BenchmarkLestrratCachedWriter-4 1000000 3390 ns/op 192 B/op 3 allocs/op
+PASS
+ok github.com/lestrrat-go/strftime 44.854s
+```
+
+This library is much faster than other libraries *IF* you can reuse the format pattern.
+
+Here's the annotated list from the benchmark results. You can clearly see that (re)using a `Strftime` object
+and producing a string is the fastest. Writing to an `io.Writer` seems a bit sluggish, but since
+the one producing the string is doing almost exactly the same thing, we believe this is purely the overhead of
+writing to an `io.Writer`
+
+| Import Path | Score | Note |
+|:------------------------------------|--------:|:--------------------------------|
+| github.com/lestrrat-go/strftime | 3000000 | Using `FormatString()` (cached) |
+| github.com/fastly/go-utils/strftime | 2000000 | Pure go version on OS X |
+| github.com/lestrrat-go/strftime | 1000000 | Using `Format()` (NOT cached) |
+| github.com/jehiah/go-strftime | 1000000 | |
+| github.com/fastly/go-utils/strftime | 1000000 | cgo version on Linux |
+| github.com/lestrrat-go/strftime | 500000 | Using `Format()` (cached) |
+| github.com/tebeka/strftime | 300000 | |
+
+However, depending on your pattern, this speed may vary. If you find a particular pattern that seems sluggish,
+please send in patches or tests.
+
+Please also note that this benchmark only uses the subset of conversion specifications that are supported by *ALL* of the libraries compared.
+
+Somethings to consider when making performance comparisons in the future:
+
+* Can it write to io.Writer?
+* Which `%specification` does it handle?
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