v1.5.5 (Apr 2023)
fix: fix rare corruption bug affecting the high compression mode, reported by @danlark1 (#3517, @terrelln)
perf: improve mid-level compression speed (#3529, #3533, #3543, @yoniko and #3552, @terrelln)
lib: deprecated bufferless block-level API (#3534) by @terrelln
cli: mmap large dictionaries to save memory, by @daniellerozenblit
cli: improve speed of --patch-from mode (~+50%) (#3545) by @daniellerozenblit
cli: improve i/o speed (~+10%) when processing lots of small files (#3479) by @felixhandte
cli: zstd no longer crashes when requested to write into write-protected directory (#3541) by @felixhandte
cli: fix decompression into block device using -o, reported by @georgmu (#3583)
build: fix zstd CLI compiled with lzma support but not zlib support (#3494) by @Hello71
build: fix cmake does no longer require 3.18 as minimum version (#3510) by @kou
build: fix MSVC+ClangCL linking issue (#3569) by @tru
build: fix zstd-dll, version of zstd CLI that links to the dynamic library (#3496) by @yoniko
build: fix MSVC warnings (#3495) by @embg
doc: updated zstd specification to clarify corner cases, by @Cyan4973
doc: document how to create fat binaries for macos (#3568) by @rickmark
misc: improve seekable format ingestion speed (~+100%) for very small chunk sizes (#3544) by @Cyan4973
misc: tests/fullbench can benchmark multiple files (#3516) by @dloidolt

v1.5.4 (Feb 2023)
perf: +20% faster huffman decompression for targets that can't compile x64 assembly (#3449, @terrelln)
perf: up to +10% faster streaming compression at levels 1-2 (#3114, @embg)
perf: +4-13% for levels 5-12 by optimizing function generation (#3295, @terrelln)
pref: +3-11% compression speed for `arm` target (#3199, #3164, #3145, #3141, #3138, @JunHe77 and #3139, #3160, @danlark1)
perf: +5-30% faster dictionary compression at levels 1-4 (#3086, #3114, #3152, @embg)
perf: +10-20% cold dict compression speed by prefetching CDict tables (#3177, @embg)
perf: +1% faster compression by removing a branch in ZSTD_fast_noDict (#3129, @felixhandte)
perf: Small compression ratio improvements in high compression mode (#2983, #3391, @Cyan4973 and #3285, #3302, @daniellerozenblit)
perf: small speed improvement by better detecting `STATIC_BMI2` for `clang` (#3080, @TocarIP)
perf: Improved streaming performance when `ZSTD_c_stableInBuffer` is set (#2974, @Cyan4973)
cli: Asynchronous I/O for improved cli speed (#2975, #2985, #3021, #3022, @yoniko)
cli: Change `zstdless` behavior to align with `zless` (#2909, @binhdvo)
cli: Keep original file if `-c` or `--stdout` is given (#3052, @dirkmueller)
cli: Keep original files when result is concatenated into a single output with `-o` (#3450, @Cyan4973)
cli: Preserve Permissions and Ownership of regular files (#3432, @felixhandte)
cli: Print zlib/lz4/lzma library versions with `-vv` (#3030, @terrelln)
cli: Print checksum value for single frame files with `-lv`  (#3332, @Cyan4973)
cli: Print `dictID` when present with `-lv` (#3184, @htnhan)
cli: when `stderr` is *not* the console, disable status updates, but preserve final summary (#3458, @Cyan4973)
cli: support `--best` and `--no-name` in `gzip` compatibility mode (#3059, @dirkmueller)
cli: support for `posix` high resolution timer `clock_gettime()`, for improved benchmark accuracy (#3423, @Cyan4973)
cli: improved help/usage (`-h`,  `-H`) formatting (#3094, @dirkmueller and #3385, @jonpalmisc)
cli: Fix better handling of bogus numeric values (#3268, @ctkhanhly)
cli: Fix input consists of multiple files _and_ `stdin` (#3222, @yoniko)
cli: Fix tiny files passthrough (#3215, @cgbur)
cli: Fix for `-r` on empty directory (#3027, @brailovich)
cli: Fix empty string as argument for `--output-dir-*` (#3220, @embg)
cli: Fix decompression memory usage reported by `-vv --long` (#3042, @u1f35c, and #3232, @zengyijing)
cli: Fix infinite loop when empty input is passed to trainer (#3081, @terrelln)
cli: Fix `--adapt` doesn't work when `--no-progress` is also set (#3354, @terrelln)
api: Support for Block-Level Sequence Producer (#3333, @embg)
api: Support for in-place decompression (#3432, @terrelln)
api: New  `ZSTD_CCtx_setCParams()`  function, set all parameters defined in a  `ZSTD_compressionParameters`  structure (#3403, @Cyan4973)
api: Streaming decompression detects incorrect header ID sooner (#3175, @Cyan4973)
api: Window size resizing optimization for edge case (#3345, @daniellerozenblit)
api: More accurate error codes for busy-loop scenarios (#3413, #3455, @Cyan4973)
api: Fix limit overflow in `compressBound` and `decompressBound` (#3362, #3373, Cyan4973) reported by @nigeltao
api: Deprecate several advanced experimental functions: streaming (#3408, @embg), copy (#3196, @mileshu)
bug: Fix corruption that rarely occurs in 32-bit mode with wlog=25 (#3361, @terrelln)
bug: Fix for block-splitter (#3033, @Cyan4973)
bug: Fixes for Sequence Compression API (#3023, #3040, @Cyan4973)
bug: Fix leaking thread handles on Windows (#3147, @animalize)
bug: Fix timing issues with cmake/meson builds (#3166, #3167, #3170, @Cyan4973)
build: Allow user to select legacy level for cmake (#3050, @shadchin)
build: Enable legacy support by default in cmake (#3079, @niamster)
build: Meson build script improvements (#3039, #3120, #3122, #3327, #3357, @eli-schwartz and #3276, @neheb)
build: Add aarch64 to supported architectures for zstd_trace (#3054, @ooosssososos)
build: support AIX architecture (#3219, @qiongsiwu)
build: Fix `ZSTD_LIB_MINIFY` build macro, which now reduces static library size by half (#3366, @terrelln)
build: Fix Windows issues with Multithreading translation layer (#3364, #3380, @yoniko) and ARM64 target (#3320, @cwoffenden)
build: Fix `cmake` script (#3382, #3392, @terrelln and #3252 @Tachi107 and #3167 @Cyan4973)
doc: Updated man page, providing more details for `--train` mode (#3112, @Cyan4973)
doc: Add decompressor errata document (#3092, @terrelln)
misc: Enable Intel CET (#2992, #2994, @hjl-tools)
misc: Fix `contrib/` seekable format (#3058, @yhoogstrate and #3346, @daniellerozenblit)
misc: Improve speed of the one-file library generator (#3241, @wahern and #3005, @cwoffenden)

v1.5.3 (dev version, unpublished)

v1.5.2 (Jan, 2022)
perf: Regain Minimal memset()-ing During Reuse of Compression Contexts (@Cyan4973, #2969)
build: Build Zstd with `noexecstack` on All Architectures (@felixhandte, #2964)
doc: Clarify Licensing (@terrelln, #2981)

v1.5.1 (Dec, 2021)
perf: rebalanced compression levels, to better match the intended speed/level curve, by @senhuang42
perf: faster huffman decoder, using x64 assembly, by @terrelln
perf: slightly faster high speed modes (strategies fast & dfast), by @felixhandte
perf: improved binary size and faster compilation times, by @terrelln
perf: new row64 mode, used notably in level 12, by @senhuang42
perf: faster mid-level compression speed in presence of highly repetitive patterns, by @senhuang42
perf: minor compression ratio improvements for small data at high levels, by @cyan4973
perf: reduced stack usage (mostly useful for Linux Kernel), by @terrelln
perf: faster compression speed on incompressible data, by @bindhvo
perf: on-demand reduced ZSTD_DCtx state size, using build macro ZSTD_DECODER_INTERNAL_BUFFER, at a small cost of performance, by @bindhvo
build: allows hiding static symbols in the dynamic library, using build macro, by @skitt
build: support for m68k (Motorola 68000's), by @cyan4973
build: improved AIX support, by @Helflym
build: improved meson unofficial build, by @eli-schwartz
cli : custom memory limit when training dictionary (#2925), by @embg
cli : report advanced parameters information when compressing in very verbose mode (``-vv`), by @Svetlitski-FB

v1.5.0  (May 11, 2021)
api: Various functions promoted from experimental to stable API: (#2579-2581, @senhuang42)
  `ZSTD_defaultCLevel()`
  `ZSTD_getDictID_fromCDict()`
api: Several experimental functions have been deprecated and will emit a compiler warning (#2582, @senhuang42)
  `ZSTD_compress_advanced()`
  `ZSTD_compress_usingCDict_advanced()`
  `ZSTD_compressBegin_advanced()`
  `ZSTD_compressBegin_usingCDict_advanced()`
  `ZSTD_initCStream_srcSize()`
  `ZSTD_initCStream_usingDict()`
  `ZSTD_initCStream_usingCDict()`
  `ZSTD_initCStream_advanced()`
  `ZSTD_initCStream_usingCDict_advanced()`
  `ZSTD_resetCStream()`
api: ZSTDMT_NBWORKERS_MAX reduced to 64 for 32-bit environments (@Cyan4973)
perf: Significant speed improvements for middle compression levels (#2494, @senhuang42 @terrelln)
perf: Block splitter to improve compression ratio, enabled by default for high compression levels (#2447, @senhuang42)
perf: Decompression loop refactor, speed improvements on `clang` and for `--long` modes (#2614 #2630, @Cyan4973)
perf: Reduced stack usage during compression and decompression entropy stage (#2522 #2524, @terrelln)
bug: Improve setting permissions of created files (#2525, @felixhandte)
bug: Fix large dictionary non-determinism (#2607, @terrelln)
bug: Fix non-determinism test failures on Linux i686 (#2606, @terrelln)
bug: Fix various dedicated dictionary search bugs (#2540 #2586, @senhuang42 @felixhandte)
bug: Ensure `ZSTD_estimateCCtxSize*() `monotonically increases with compression level (#2538, @senhuang42)
bug: Fix --patch-from mode parameter bound bug with small files (#2637, @occivink)
bug: Fix UBSAN error in decompression (#2625, @terrelln)
bug: Fix superblock compression divide by zero bug (#2592, @senhuang42)
bug: Make the number of physical CPU cores detection more robust (#2517, @PaulBone)
doc: Improve `zdict.h` dictionary training API documentation (#2622, @terrelln)
doc: Note that public `ZSTD_free*()` functions accept NULL pointers (#2521, @animalize)
doc: Add style guide docs for open source contributors (#2626, @Cyan4973)
tests: Better regression test coverage for different dictionary modes (#2559, @senhuang42)
tests: Better test coverage of index reduction (#2603, @terrelln)
tests: OSS-Fuzz coverage for seekable format (#2617, @senhuang42)
tests: Test coverage for ZSTD threadpool API (#2604, @senhuang42)
build: Dynamic library built multithreaded by default (#2584, @senhuang42)
build: Move  `zstd_errors.h`  and  `zdict.h`  to  `lib/`  root (#2597, @terrelln)
build: Allow `ZSTDMT_JOBSIZE_MIN` to be configured at compile-time, reduce default to 512KB (#2611, @Cyan4973)
build: Single file library build script moved to `build/` directory (#2618, @felixhandte)
build: `ZBUFF_*()` is no longer built by default (#2583, @senhuang42)
build: Fixed Meson build (#2548, @SupervisedThinking @kloczek)
build: Fix excessive compiler warnings with clang-cl and CMake (#2600, @nickhutchinson)
build: Detect presence of `md5` on Darwin (#2609, @felixhandte)
build: Avoid SIGBUS on armv6 (#2633, @bmwiedmann)
cli: `--progress` flag added to always display progress bar (#2595, @senhuang42)
cli: Allow reading from block devices with `--force` (#2613, @felixhandte)
cli: Fix CLI filesize display bug (#2550, @Cyan4973)
cli: Fix windows CLI `--filelist` end-of-line bug (#2620, @Cyan4973)
contrib: Various fixes for linux kernel patch (#2539, @terrelln)
contrib: Seekable format - Decompression hanging edge case fix (#2516, @senhuang42)
contrib: Seekable format - New seek table-only API  (#2113 #2518, @mdittmer @Cyan4973)
contrib: Seekable format - Fix seek table descriptor check when loading (#2534, @foxeng)
contrib: Seekable format - Decompression fix for large offsets, (#2594, @azat)
misc: Automatically published release tarballs available on Github (#2535, @felixhandte)

v1.4.9  (Mar 1, 2021)
bug: Use `umask()` to Constrain Created File Permissions (#2495, @felixhandte)
bug: Make Simple Single-Pass Functions Ignore Advanced Parameters (#2498, @terrelln)
api: Add (De)Compression Tracing Functionality (#2482, @terrelln)
api: Support References to Multiple DDicts (#2446, @senhuang42)
api: Add Function to Generate Skippable Frame (#2439, @senhuang42)
perf: New Algorithms for the Long Distance Matcher (#2483, @mpu)
perf: Performance Improvements for Long Distance Matcher (#2464, @mpu)
perf: Don't Shrink Window Log when Streaming with a Dictionary (#2451, @terrelln)
cli: Fix `--output-dir-mirror`'s Rejection of `..`-Containing Paths (#2512, @felixhandte)
cli: Allow Input From Console When `-f`/`--force` is Passed (#2466, @felixhandte)
cli: Improve Help Message (#2500, @senhuang42)
tests: Remove Flaky Tests (#2455, #2486, #2445, @Cyan4973)
tests: Correctly Invoke md5 Utility on NetBSD (#2492, @niacat)
tests: Avoid Using `stat -c` on NetBSD (#2513, @felixhandte)
build: Zstd CLI Can Now be Linked to Dynamic `libzstd` (#2457, #2454 @Cyan4973)
build: Hide and Avoid Using Static-Only Symbols (#2501, #2504, @skitt)
build: CMake: Enable Only C for lib/ and programs/ Projects (#2498, @concatime)
build: CMake: Use `configure_file()` to Create the `.pc` File (#2462, @lazka)
build: Fix Fuzzer Compiler Detection & Update UBSAN Flags (#2503, @terrelln)
build: Add Guards for `_LARGEFILE_SOURCE` and `_LARGEFILE64_SOURCE` (#2444, @indygreg)
build: Improve `zlibwrapper` Makefile (#2437, @Cyan4973)
contrib: Add `recover_directory` Program (#2473, @terrelln)
doc: Change License Year to 2021 (#2452 & #2465, @terrelln & @senhuang42)
doc: Fix Typos (#2459, @ThomasWaldmann)

v1.4.8  (Dec 18, 2020)
hotfix: wrong alignment of an internal buffer

v1.4.7  (Dec 16, 2020)
perf: stronger --long mode at high compression levels, by @senhuang42
perf: stronger --patch-from at high compression levels, thanks to --long improvements
perf: faster dictionary compression at medium compression levels, by @felixhandte
perf: small speed & memory usage improvements for ZSTD_compress2(), by @terrelln
perf: improved fast compression speeds with Visual Studio, by @animalize
cli : Set nb of threads with environment variable ZSTD_NBTHREADS, by @senhuang42
cli : accept decompressing files with *.zstd suffix
cli : provide a condensed summary by default when processing multiple files
cli : fix : stdin input no longer confused as user prompt
cli : improve accuracy of several error messages
api : new sequence ingestion API, by @senhuang42
api : shared thread pool: control total nb of threads used by multiple compression jobs, by @marxin
api : new ZSTD_getDictID_fromCDict(), by @LuAPi
api : zlibWrapper only uses public API, and is compatible with dynamic library, by @terrelln
api : fix : multithreaded compression has predictable output even in special cases (see #2327) (issue not accessible from cli)
api : fix : dictionary compression correctly respects dictionary compression level (see #2303) (issue not accessible from cli)
build: fix cmake script when using path with spaces, by @terrelln
build: improved compile-time detection of aarch64/neon platforms, by @bsdimp
build: Fix building on AIX 5.1, by @likema
build: compile paramgrill with cmake on Windows, requested by @mirh
doc : clarify repcode updates in format specification, by @felixhandte

v1.4.6
fix : Always return dstSize_tooSmall when that is the case
fix : Fix ZSTD_initCStream_advanced() with static allocation and no dictionary
perf: Improve small block decompression speed by 20%+, by @terrelln
perf: Reduce compression stack usage by 1 KB, by @terrelln
perf: Improve decompression speed by improving ZSTD_wildcopy, by @helloguo (#2252, #2256)
perf: Improve histogram construction, by @cyan4973 (#2253)
cli : Add --output-dir-mirror option, by @xxie24 (#2219)
cli : Warn when (de)compressing multiple files into a single output, by @senhuang42 (#2279)
cli : Improved progress bar and status summary when (de)compressing multiple files, by @senhuang42 (#2283)
cli : Call stat less often, by @felixhandte (#2262)
cli : Allow --patch-from XXX and --filelist XXX in addition to --patch-from=XXX and --filelist=XXX, by @cyan4973 (#2250)
cli : Allow --patch-from to compress stdin with --stream-size, by @bimbashrestha (#2206)
api : Do not install zbuff.h, since it has long been deprecated, by @cyan4973 (#2166).
api : Fix ZSTD_CCtx_setParameter() with ZSTD_c_compressionLevel to make 0 mean default level, by @i-do-cpp (#2291)
api : Rename ZSTDMT_NBTHREADS_MAX to ZSTDMT_NBWORKERS_MAX, by @marxin (#2228).
build: Install pkg-config file with CMake and MinGW, by @tonytheodore (#2183)
build: Install DLL with CMake on Windows, by @BioDataAnalysis (#2221)
build: Fix DLL install location with CMake, by @xantares and @bimbashrestha (#2186)
build: Add ZSTD_NO_UNUSED_FUNCTIONS macro to hide unused functions
build: Add ZSTD_NO_INTRINSICS macro to avoid explicit intrinsics
build: Add STATIC_BMI2 macro for compile time detection of BMI2 on MSVC, by @Niadb (#2258)
build: Fix -Wcomma warnings, by @cwoffenden
build: Remove distutils requirement for meson build, by @neheb (#2197)
build: Fix cli compilation with uclibc
build: Fix cli compilation without st_mtime, by @ffontaine (#2246)
build: Fix shadowing warnings in library
build: Fix single file library compilation with Enscripten, by @yoshihitoh (#2227)
misc: Improve single file library and include dictBuilder, by @cwoffenden
misc: Allow compression dictionaries with missing symbols
misc: Add freestanding translation script in contrib/freestanding_lib
misc: Collect all of zstd's libc dependencies into zstd_deps.h
doc : Add ZSTD_versionString() to manual, by @animalize
doc : Fix documentation for ZSTD_CCtxParams_setParameter(), by @felixhandte (#2270)

v1.4.5  (May 22, 2020)
fix : Compression ratio regression on huge files (> 3 GB) using high levels (--ultra) and multithreading, by @terrelln
perf: Improved decompression speed: x64 : +10% (clang) / +5% (gcc); ARM : from +15% to +50%, depending on SoC, by @terrelln
perf: Automatically downsizes ZSTD_DCtx when too large for too long (#2069, by @bimbashreshta)
perf: Improved fast compression speed on aarch64 (#2040, ~+3%, by @caoyzh)
perf: Small level 1 compression speed gains (depending on compiler)
cli : New --patch-from command, create and apply patches from files, by @bimbashreshta
cli : New --filelist= : Provide a list of files to operate upon from a file
cli : -b -d command can now benchmark decompression on multiple files
cli : New --no-content-size command
cli : New --show-default-cparams information command
api : ZDICT_finalizeDictionary() is promoted to stable (#2111)
api : new experimental parameter ZSTD_d_stableOutBuffer (#2094)
build: Generate a single-file libzstd library (#2065, by @cwoffenden)
build: Relative includes no longer require -I compiler flags for zstd lib subdirs (#2103, by @felixhandte)
build: zstd now compiles cleanly under -pedantic (#2099)
build: zstd now compiles with make-4.3
build: Support mingw cross-compilation from Linux, by @Ericson2314
build: Meson multi-thread build fix on windows
build: Some misc icc fixes backed by new ci test on travis
misc: bitflip analyzer tool, by @felixhandte
misc: Extend largeNbDicts benchmark to compression
misc: Edit-distance match finder in contrib/
doc : Improved beginner CONTRIBUTING.md docs
doc : New issue templates for zstd

v1.4.4  (Nov 6, 2019)
perf: Improved decompression speed, by > 10%, by @terrelln
perf: Better compression speed when re-using a context, by @felixhandte
perf: Fix compression ratio when compressing large files with small dictionary, by @senhuang42
perf: zstd reference encoder can generate RLE blocks, by @bimbashrestha
perf: minor generic speed optimization, by @davidbolvansky
api: new ability to extract sequences from the parser for analysis, by @bimbashrestha
api: fixed decoding of magic-less frames, by @terrelln
api: fixed ZSTD_initCStream_advanced() performance with fast modes, reported by @QrczakMK
cli: Named pipes support, by @bimbashrestha
cli: short tar's extension support, by @stokito
cli: command --output-dir-flat= , generates target files into requested directory, by @senhuang42
cli: commands --stream-size=# and --size-hint=#, by @nmagerko
cli: command --exclude-compressed, by @shashank0791
cli: faster `-t` test mode
cli: improved some error messages, by @vangyzen
cli: fix command `-D dictionary` on Windows, reported by @artyompetrov
cli: fix rare deadlock condition within dictionary builder, by @terrelln
build: single-file decoder with emscripten compilation script, by @cwoffenden
build: fixed zlibWrapper compilation on Visual Studio, reported by @bluenlive
build: fixed deprecation warning for certain gcc version, reported by @jasonma163
build: fix compilation on old gcc versions, by @cemeyer
build: improved installation directories for cmake script, by Dmitri Shubin
pack: modified pkgconfig, for better integration into openwrt, requested by @neheb
misc: Improved documentation : ZSTD_CLEVEL, DYNAMIC_BMI2, ZSTD_CDict, function deprecation, zstd format
misc: fixed educational decoder : accept larger literals section, and removed UNALIGNED() macro

v1.4.3  (Aug 20, 2019)
bug: Fix Dictionary Compression Ratio Regression by @cyan4973 (#1709)
bug: Fix Buffer Overflow in legacy v0.3 decompression by @felixhandte (#1722)
build: Add support for IAR C/C++ Compiler for Arm by @joseph0918 (#1705)

v1.4.2  (Jul 26, 2019)
bug: Fix bug in zstd-0.5 decoder by @terrelln (#1696)
bug: Fix seekable decompression in-memory API by @iburinoc (#1695)
misc: Validate blocks are smaller than size limit by @vivekmg (#1685)
misc: Restructure source files by @ephiepark (#1679)

v1.4.1  (Jul 20, 2019)
bug: Fix data corruption in niche use cases by @terrelln (#1659)
bug: Fuzz legacy modes, fix uncovered bugs by @terrelln (#1593, #1594, #1595)
bug: Fix out of bounds read by @terrelln (#1590)
perf: Improve decode speed by ~7% @mgrice (#1668)
perf: Slightly improved compression ratio of level 3 and 4 (ZSTD_dfast) by @cyan4973 (#1681)
perf: Slightly faster compression speed when re-using a context by @cyan4973 (#1658)
perf: Improve compression ratio for small windowLog by @cyan4973 (#1624)
perf: Faster compression speed in high compression mode for repetitive data by @terrelln (#1635)
api: Add parameter to generate smaller dictionaries by @tyler-tran (#1656)
cli: Recognize symlinks when built in C99 mode by @felixhandte (#1640)
cli: Expose cpu load indicator for each file on -vv mode by @ephiepark (#1631)
cli: Restrict read permissions on destination files by @chungy (#1644)
cli: zstdgrep: handle -f flag by @felixhandte (#1618)
cli: zstdcat: follow symlinks by @vejnar (#1604)
doc: Remove extra size limit on compressed blocks by @felixhandte (#1689)
doc: Fix typo by @yk-tanigawa (#1633)
doc: Improve documentation on streaming buffer sizes by @cyan4973 (#1629)
build: CMake: support building with LZ4 @leeyoung624 (#1626)
build: CMake: install zstdless and zstdgrep by @leeyoung624 (#1647)
build: CMake: respect existing uninstall target by @j301scott (#1619)
build: Make: skip multithread tests when built without support by @michaelforney (#1620)
build: Make: Fix examples/ test target by @sjnam (#1603)
build: Meson: rename options out of deprecated namespace by @lzutao (#1665)
build: Meson: fix build by @lzutao (#1602)
build: Visual Studio: don't export symbols in static lib by @scharan (#1650)
build: Visual Studio: fix linking by @absotively (#1639)
build: Fix MinGW-W64 build by @myzhang1029 (#1600)
misc: Expand decodecorpus coverage by @ephiepark (#1664)

v1.4.0  (Apr 17, 2019)
perf: Improve level 1 compression speed in most scenarios by 6% by @gbtucker and @terrelln
api: Move the advanced API, including all functions in the staging section, to the stable section
api: Make ZSTD_e_flush and ZSTD_e_end block for maximum forward progress
api: Rename ZSTD_CCtxParam_getParameter to ZSTD_CCtxParams_getParameter
api: Rename ZSTD_CCtxParam_setParameter to ZSTD_CCtxParams_setParameter
api: Don't export ZSTDMT functions from the shared library by default
api: Require ZSTD_MULTITHREAD to be defined to use ZSTDMT
api: Add ZSTD_decompressBound() to provide an upper bound on decompressed size by @shakeelrao
api: Fix ZSTD_decompressDCtx() corner cases with a dictionary
api: Move ZSTD_getDictID_*() functions to the stable section
api: Add ZSTD_c_literalCompressionMode flag to enable or disable literal compression by @terrelln
api: Allow compression parameters to be set when a dictionary is used
api: Allow setting parameters before or after ZSTD_CCtx_loadDictionary() is called
api: Fix ZSTD_estimateCStreamSize_usingCCtxParams()
api: Setting ZSTD_d_maxWindowLog to 0 means use the default
cli: Ensure that a dictionary is not used to compress itself by @shakeelrao
cli: Add --[no-]compress-literals flag to enable or disable literal compression
doc: Update the examples to use the advanced API
doc: Explain how to transition from old streaming functions to the advanced API in the header
build: Improve the Windows release packages
build: Improve CMake build by @hjmjohnson
build: Build fixes for FreeBSD by @lwhsu
build: Remove redundant warnings by @thatsafunnyname
build: Fix tests on OpenBSD by @bket
build: Extend fuzzer build system to work with the new clang engine
build: CMake now creates the libzstd.so.1 symlink
build: Improve Menson build by @lzutao
misc: Fix symbolic link detection on FreeBSD
misc: Use physical core count for -T0 on FreeBSD by @cemeyer
misc: Fix zstd --list on truncated files by @kostmo
misc: Improve logging in debug mode by @felixhandte
misc: Add CirrusCI tests by @lwhsu
misc: Optimize dictionary memory usage in corner cases
misc: Improve the dictionary builder on small or homogeneous data
misc: Fix spelling across the repo by @jsoref

v1.3.8  (Dec 28, 2018)
perf: better decompression speed on large files (+7%) and cold dictionaries (+15%)
perf: slightly better compression ratio at high compression modes
api : finalized advanced API, last stage before "stable" status
api : new --rsyncable mode, by @terrelln
api : support decompression of empty frames into NULL (used to be an error) (#1385)
build: new set of macros to build a minimal size decoder, by @felixhandte
build: fix compilation on MIPS32, reported by @clbr (#1441)
build: fix compilation with multiple -arch flags, by @ryandesign
build: highly upgraded meson build, by @lzutao
build: improved buck support, by @obelisk
build: fix cmake script : can create debug build, by @pitrou
build: Makefile : grep works on both colored consoles and systems without color support
build: fixed zstd-pgo, by @bmwiedemann
cli : support ZSTD_CLEVEL environment variable, by @yijinfb (#1423)
cli : --no-progress flag, preserving final summary (#1371), by @terrelln
cli : ensure destination file is not source file (#1422)
cli : clearer error messages, especially when input file not present
doc : clarified zstd_compression_format.md, by @ulikunitz
misc: fixed zstdgrep, returns 1 on failure, by @lzutao
misc: NEWS renamed as CHANGELOG, in accordance with fboss

v1.3.7  (Oct 20, 2018)
perf: slightly better decompression speed on clang (depending on hardware target)
fix : performance of dictionary compression for small input < 4 KB at levels 9 and 10
build: no longer build backtrace by default in release mode; restrict further automatic mode
build: control backtrace support through build macro BACKTRACE
misc: added man pages for zstdless and zstdgrep, by @samrussell

v1.3.6  (Oct 6, 2018)
perf: much faster dictionary builder, by @jenniferliu
perf: faster dictionary compression on small data when using multiple contexts, by @felixhandte
perf: faster dictionary decompression when using a very large number of dictionaries simultaneously
cli : fix : does no longer overwrite destination when source does not exist (#1082)
cli : new command --adapt, for automatic compression level adaptation
api : fix : block api can be streamed with > 4 GB, reported by @catid
api : reduced ZSTD_DDict size by 2 KB
api : minimum negative compression level is defined, and can be queried using ZSTD_minCLevel().
build: support Haiku target, by @korli
build: Read Legacy format is limited to v0.5+ by default. Can be changed at compile time with macro ZSTD_LEGACY_SUPPORT.
doc : zstd_compression_format.md updated to match wording in IETF RFC 8478
misc: tests/paramgrill, a parameter optimizer, by @GeorgeLu97

v1.3.5  (Jun 29, 2018)
perf: much faster dictionary compression, by @felixhandte
perf: small quality improvement for dictionary generation, by @terrelln
perf: slightly improved high compression levels (notably level 19)
mem : automatic memory release for long duration contexts
cli : fix : overlapLog can be manually set
cli : fix : decoding invalid lz4 frames
api : fix : performance degradation for dictionary compression when using advanced API, by @terrelln
api : change : clarify ZSTD_CCtx_reset() vs ZSTD_CCtx_resetParameters(), by @terrelln
build: select custom libzstd scope through control macros, by @GeorgeLu97
build: OpenBSD patch, by @bket
build: make and make all are compatible with -j
doc : clarify zstd_compression_format.md, updated for IETF RFC process
misc: pzstd compatible with reproducible compilation, by @lamby

v1.3.4  (Mar 27, 2018)
perf: faster speed (especially decoding speed) on recent cpus (haswell+)
perf: much better performance associating --long with multi-threading, by @terrelln
perf: better compression at levels 13-15
cli : asynchronous compression by default, for faster experience (use --single-thread for former behavior)
cli : smoother status report in multi-threading mode
cli : added command --fast=#, for faster compression modes
cli : fix crash when not overwriting existing files, by Pádraig Brady (@pixelb)
api : `nbThreads` becomes `nbWorkers` : 1 triggers asynchronous mode
api : compression levels can be negative, for even more speed
api : ZSTD_getFrameProgression() : get precise progress status of ZSTDMT anytime
api : ZSTDMT can accept new compression parameters during compression
api : implemented all advanced dictionary decompression prototypes
build: improved meson recipe, by Shawn Landden (@shawnl)
build: VS2017 scripts, by @HaydnTrigg
misc: all /contrib projects fixed
misc: added /contrib/docker script by @gyscos

v1.3.3  (Dec 21, 2017)
perf: faster zstd_opt strategy (levels 16-19)
fix : bug #944 : multithreading with shared ditionary and large data, reported by @gsliepen
cli : fix : content size written in header by default
cli : fix : improved LZ4 format support, by @felixhandte
cli : new : hidden command `-S`, to benchmark multiple files while generating one result per file
api : fix : support large skippable frames, by @terrelln
api : fix : streaming interface was adding a useless 3-bytes null block to small frames
api : change : when setting `pledgedSrcSize`, use `ZSTD_CONTENTSIZE_UNKNOWN` macro value to mean "unknown"
build: fix : compilation under rhel6 and centos6, reported by @pixelb
build: added `check` target

v1.3.2  (Oct 10, 2017)
new : long range mode, using --long command, by Stella Lau (@stellamplau)
new : ability to generate and decode magicless frames (#591)
changed : maximum nb of threads reduced to 200, to avoid address space exhaustion in 32-bits mode
fix : multi-threading compression works with custom allocators
fix : ZSTD_sizeof_CStream() was over-evaluating memory usage
fix : a rare compression bug when compression generates very large distances and bunch of other conditions (only possible at --ultra -22)
fix : 32-bits build can now decode large offsets (levels 21+)
cli : added LZ4 frame support by default, by Felix Handte (@felixhandte)
cli : improved --list output
cli : new : can split input file for dictionary training, using command -B#
cli : new : clean operation artefact on Ctrl-C interruption
cli : fix : do not change /dev/null permissions when using command -t with root access, reported by @mike155 (#851)
cli : fix : write file size in header in multiple-files mode
api : added macro ZSTD_COMPRESSBOUND() for static allocation
api : experimental : new advanced decompression API
api : fix : sizeof_CCtx() used to over-estimate
build: fix : no-multithread variant compiles without pool.c dependency, reported by Mitchell Blank Jr (@mitchblank) (#819)
build: better compatibility with reproducible builds, by Bernhard M. Wiedemann (@bmwiedemann) (#818)
example : added streaming_memory_usage
license : changed /examples license to BSD + GPLv2
license : fix a few header files to reflect new license (#825)

v1.3.1  (Aug 21, 2017)
New license : BSD + GPLv2
perf: substantially decreased memory usage in Multi-threading mode, thanks to reports by Tino Reichardt (@mcmilk)
perf: Multi-threading supports up to 256 threads. Cap at 256 when more are requested (#760)
cli : improved and fixed --list command, by @ib (#772)
cli : command -vV to list supported formats, by @ib (#771)
build : fixed binary variants, reported by @svenha (#788)
build : fix Visual compilation for non x86/x64 targets, reported by Greg Slazinski (@GregSlazinski) (#718)
API exp : breaking change : ZSTD_getframeHeader() provides more information
API exp : breaking change : pinned down values of error codes
doc : fixed huffman example, by Ulrich Kunitz (@ulikunitz)
new : contrib/adaptive-compression, I/O driven compression strength, by Paul Cruz (@paulcruz74)
new : contrib/long_distance_matching, statistics by Stella Lau (@stellamplau)
updated : contrib/linux-kernel, by Nick Terrell (@terrelln)

v1.3.0  (Jul 6, 2017)
cli : new : `--list` command, by Paul Cruz
cli : changed : xz/lzma support enabled by default
cli : changed : `-t *` continue processing list after a decompression error
API : added : ZSTD_versionString()
API : promoted to stable status : ZSTD_getFrameContentSize(), by Sean Purcell
API exp : new advanced API : ZSTD_compress_generic(), ZSTD_CCtx_setParameter()
API exp : new : API for static or external allocation : ZSTD_initStatic?Ctx()
API exp : added : ZSTD_decompressBegin_usingDDict(), requested by Guy Riddle (#700)
API exp : clarified memory estimation / measurement functions.
API exp : changed : strongest strategy renamed ZSTD_btultra, fastest strategy ZSTD_fast set to 1
tools : decodecorpus can generate random dictionary-compressed samples, by Paul Cruz
new : contrib/seekable_format, demo and API, by Sean Purcell
changed : contrib/linux-kernel, updated version and license, by Nick Terrell

v1.2.0  (May 5, 2017)
cli : changed : Multithreading enabled by default (use target zstd-nomt or HAVE_THREAD=0 to disable)
cli : new : command -T0 means "detect and use nb of cores", by Sean Purcell
cli : new : zstdmt symlink hardwired to `zstd -T0`
cli : new : command --threads=# (#671)
cli : changed : cover dictionary builder by default, for improved quality, by Nick Terrell
cli : new : commands --train-cover and --train-legacy, to select dictionary algorithm and parameters
cli : experimental targets `zstd4` and `xzstd4`, with support for lz4 format, by Sean Purcell
cli : fix : does not output compressed data on console
cli : fix : ignore symbolic links unless --force specified,
API : breaking change : ZSTD_createCDict_advanced(), only use compressionParameters as argument
API : added : prototypes ZSTD_*_usingCDict_advanced(), for direct control over frameParameters.
API : improved: ZSTDMT_compressCCtx() reduced memory usage
API : fix : ZSTDMT_compressCCtx() now provides srcSize in header (#634)
API : fix : src size stored in frame header is controlled at end of frame
API : fix : enforced consistent rules for pledgedSrcSize==0 (#641)
API : fix : error code "GENERIC" replaced by "dstSizeTooSmall" when appropriate
build: improved cmake script, by @Majlen
build: enabled Multi-threading support for *BSD, by Baptiste Daroussin
tools: updated Paramgrill. Command -O# provides best parameters for sample and speed target.
new : contrib/linux-kernel version, by Nick Terrell

v1.1.4  (Mar 18, 2017)
cli : new : can compress in *.gz format, using --format=gzip command, by Przemyslaw Skibinski
cli : new : advanced benchmark command --priority=rt
cli : fix : write on sparse-enabled file systems in 32-bits mode, by @ds77
cli : fix : --rm remains silent when input is stdin
cli : experimental : xzstd, with support for xz/lzma decoding, by Przemyslaw Skibinski
speed : improved decompression speed in streaming mode for single shot scenarios (+5%)
memory: DDict (decompression dictionary) memory usage down from 150 KB to 20 KB
arch: 32-bits variant able to generate and decode very long matches (>32 MB), by Sean Purcell
API : new : ZSTD_findFrameCompressedSize(), ZSTD_getFrameContentSize(), ZSTD_findDecompressedSize()
API : changed : dropped support of legacy versions <= v0.3 (can be changed by modifying ZSTD_LEGACY_SUPPORT value)
build : new: meson build system in contrib/meson, by Dima Krasner
build : improved cmake script, by @Majlen
build : added -Wformat-security flag, as recommended by Padraig Brady
doc : new : educational decoder, by Sean Purcell

v1.1.3  (Feb 7, 2017)
cli : zstd can decompress .gz files (can be disabled with `make zstd-nogz` or `make HAVE_ZLIB=0`)
cli : new : experimental target `make zstdmt`, with multi-threading support
cli : new : improved dictionary builder "cover" (experimental), by Nick Terrell, based on prior work by Giuseppe Ottaviano.
cli : new : advanced commands for detailed parameters, by Przemyslaw Skibinski
cli : fix zstdless on Mac OS-X, by Andrew Janke
cli : fix #232 "compress non-files"
dictBuilder : improved dictionary generation quality, thanks to Nick Terrell
API : new : lib/compress/ZSTDMT_compress.h multithreading API (experimental)
API : new : ZSTD_create?Dict_byReference(), requested by Bartosz Taudul
API : new : ZDICT_finalizeDictionary()
API : fix : ZSTD_initCStream_usingCDict() properly writes dictID into frame header, by Gregory Szorc (#511)
API : fix : all symbols properly exposed in libzstd, by Nick Terrell
build : support for Solaris target, by Przemyslaw Skibinski
doc : clarified specification, by Sean Purcell

v1.1.2  (Dec 15, 2016)
API : streaming : decompression : changed : automatic implicit reset when chain-decoding new frames without init
API : experimental : added : dictID retrieval functions, and ZSTD_initCStream_srcSize()
API : zbuff : changed : prototypes now generate deprecation warnings
lib : improved : faster decompression speed at ultra compression settings and 32-bits mode
lib : changed : only public ZSTD_ symbols are now exposed
lib : changed : reduced usage  of stack memory
lib : fixed : several corner case bugs, by Nick Terrell
cli : new : gzstd, experimental version able to decode .gz files, by Przemyslaw Skibinski
cli : new : preserve file attributes
cli : new : added zstdless and zstdgrep tools
cli : fixed : status displays total amount decoded, even for file consisting of multiple frames (like pzstd)
cli : fixed : zstdcat
zlib_wrapper : added support for gz* functions, by Przemyslaw Skibinski
install : better compatibility with FreeBSD, by Dimitry Andric
source tree : changed : zbuff source files moved to lib/deprecated

v1.1.1  (Nov 2, 2016)
New : command -M#, --memory=, --memlimit=, --memlimit-decompress= to limit allowed memory consumption
New : doc/zstd_manual.html, by Przemyslaw Skibinski
Improved : slightly better compression ratio at --ultra levels (>= 20)
Improved : better memory usage when using streaming compression API, thanks to @Rogier-5 report
Added : API : ZSTD_initCStream_usingCDict(), ZSTD_initDStream_usingDDict() (experimental section)
Added : example/multiple_streaming_compression.c
Changed : zstd_errors.h is now installed within /include (and replaces errors_public.h)
Updated man page
Fixed : zstd-small, zstd-compress and zstd-decompress compilation targets

v1.1.0  (Sep 28, 2016)
New : contrib/pzstd, parallel version of zstd, by Nick Terrell
added : NetBSD install target (#338)
Improved : speed for batches of small files
Improved : speed of zlib wrapper, by Przemyslaw Skibinski
Changed : libzstd on Windows supports legacy formats, by Christophe Chevalier
Fixed : CLI -d output to stdout by default when input is stdin (#322)
Fixed : CLI correctly detects console on Mac OS-X
Fixed : CLI supports recursive mode `-r` on Mac OS-X
Fixed : Legacy decoders use unified error codes, reported by benrg (#341), fixed by Przemyslaw Skibinski
Fixed : compatibility with OpenBSD, reported by Juan Francisco Cantero Hurtado (#319)
Fixed : compatibility with Hurd, by Przemyslaw Skibinski (#365)
Fixed : zstd-pgo, reported by octoploid (#329)

v1.0.0  (Sep 1, 2016)
Change Licensing, all project is now BSD, Copyright Facebook
Small decompression speed improvement
API : Streaming API supports legacy format
API : ZDICT_getDictID(), ZSTD_sizeof_{CCtx, DCtx, CStream, DStream}(), ZSTD_setDStreamParameter()
CLI supports legacy formats v0.4+
Fixed : compression fails on certain huge files, reported by Jesse McGrew
Enhanced documentation, by Przemyslaw Skibinski

v0.8.1  (Aug 18, 2016)
New streaming API
Changed : --ultra now enables levels beyond 19
Changed : -i# now selects benchmark time in second
Fixed : ZSTD_compress* can now compress > 4 GB in a single pass, reported by Nick Terrell
Fixed : speed regression on specific patterns (#272)
Fixed : support for Z_SYNC_FLUSH, by Dmitry Krot (#291)
Fixed : ICC compilation, by Przemyslaw Skibinski

v0.8.0  (Aug 2, 2016)
Improved : better speed on clang and gcc -O2, thanks to Eric Biggers
New : Build on FreeBSD and DragonFly, thanks to JrMarino
Changed : modified API : ZSTD_compressEnd()
Fixed : legacy mode with ZSTD_HEAPMODE=0, by Christopher Bergqvist
Fixed : premature end of frame when zero-sized raw block, reported by Eric Biggers
Fixed : large dictionaries (> 384 KB), reported by Ilona Papava
Fixed : checksum correctly checked in single-pass mode
Fixed : combined --test amd --rm, reported by Andreas M. Nilsson
Modified : minor compression level adaptations
Updated : compression format specification to v0.2.0
changed : zstd.h moved to /lib directory

v0.7.5  (Aug 1, 2016)
Transition version, supporting decoding of v0.8.x

v0.7.4  (Jul 17, 2016)
Added : homebrew for Mac, by Daniel Cade
Added : more examples
Fixed : segfault when using small dictionaries, reported by Felix Handte
Modified : default compression level for CLI is now 3
Updated : specification, to v0.1.1

v0.7.3  (Jul 9, 2016)
New : compression format specification
New : `--` separator, stating that all following arguments are file names. Suggested by Chip Turner.
New : `ZSTD_getDecompressedSize()`
New : OpenBSD target, by Juan Francisco Cantero Hurtado
New : `examples` directory
fixed : dictBuilder using HC levels, reported by Bartosz Taudul
fixed : legacy support from ZSTD_decompress_usingDDict(), reported by Felix Handte
fixed : multi-blocks decoding with intermediate uncompressed blocks, reported by Greg Slazinski
modified : removed "mem.h" and "error_public.h" dependencies from "zstd.h" (experimental section)
modified : legacy functions no longer need magic number

v0.7.2  (Jul 4, 2016)
fixed : ZSTD_decompressBlock() using multiple consecutive blocks. Reported by Greg Slazinski.
fixed : potential segfault on very large files (many gigabytes). Reported by Chip Turner.
fixed : CLI displays system error message when destination file cannot be created (#231). Reported by Chip Turner.

v0.7.1  (Jun 23, 2016)
fixed : ZBUFF_compressEnd() called multiple times with too small `dst` buffer, reported by Christophe Chevalier
fixed : dictBuilder fails if first sample is too small, reported by Руслан Ковалёв
fixed : corruption issue, reported by cj
modified : checksum enabled by default in command line mode

v0.7.0  (Jun 17, 2016)
New : Support for directory compression, using `-r`, thanks to Przemyslaw Skibinski
New : Command `--rm`, to remove source file after successful de/compression
New : Visual build scripts, by Christophe Chevalier
New : Support for Sparse File-systems (do not use space for zero-filled sectors)
New : Frame checksum support
New : Support pass-through mode (when using `-df`)
API : more efficient Dictionary API : `ZSTD_compress_usingCDict()`, `ZSTD_decompress_usingDDict()`
API : create dictionary files from custom content, by Giuseppe Ottaviano
API : support for custom malloc/free functions
New : controllable Dictionary ID
New : Support for skippable frames

v0.6.1  (May 13, 2016)
New : zlib wrapper API, thanks to Przemyslaw Skibinski
New : Ability to compile compressor / decompressor separately
Changed : new lib directory structure
Fixed : Legacy codec v0.5 compatible with dictionary decompression
Fixed : Decoder corruption error (#173)
Fixed : null-string roundtrip (#176)
New : benchmark mode can select directory as input
Experimental : midipix support, VMS support

v0.6.0  (Apr 13, 2016)
Stronger high compression modes, thanks to Przemyslaw Skibinski
API : ZSTD_getFrameParams() provides size of decompressed content
New : highest compression modes require `--ultra` command to fully unleash their capacity
Fixed : zstd cli return error code > 0 and removes dst file artifact when decompression fails, thanks to Chip Turner

v0.5.1  (Feb 18, 2016)
New : Optimal parsing => Very high compression modes, thanks to Przemyslaw Skibinski
Changed : Dictionary builder integrated into libzstd and zstd cli
Changed (!) : zstd cli now uses "multiple input files" as default mode. See `zstd -h`.
Fix : high compression modes for big-endian platforms
New : zstd cli : `-t` | `--test` command

v0.5.0  (Feb 5, 2016)
New : dictionary builder utility
Changed : streaming & dictionary API
Improved : better compression of small data

v0.4.7  (Jan 22, 2016)
Improved : small compression speed improvement in HC mode
Changed : `zstd_decompress.c` has ZSTD_LEGACY_SUPPORT to 0 by default
fix : bt search bug

v0.4.6  (Jan 13, 2016)
fix : fast compression mode on Windows
New : cmake configuration file, thanks to Artyom Dymchenko
Improved : high compression mode on repetitive data
New : block-level API
New : ZSTD_duplicateCCtx()

v0.4.5  (Dec 18, 2015)
new : -m/--multiple : compress/decompress multiple files

v0.4.4  (Dec 14, 2015)
Fixed : high compression modes for Windows 32 bits
new : external dictionary API extended to buffered mode and accessible through command line
new : windows DLL project, thanks to Christophe Chevalier

v0.4.3  (Dec 7, 2015)
new : external dictionary API
new : zstd-frugal

v0.4.2  (Dec 2, 2015)
Generic minor improvements for small blocks
Fixed : big-endian compatibility, by Peter Harris (#85)

v0.4.1  (Dec 1, 2015)
Fixed : ZSTD_LEGACY_SUPPORT=0 build mode (reported by Luben)
removed `zstd.c`

v0.4.0  (Nov 29, 2015)
Command line utility compatible with high compression levels
Removed zstdhc => merged into zstd
Added : ZBUFF API (see zstd_buffered.h)
Rolling buffer support

v0.3.6  (Nov 10, 2015)
small blocks params

v0.3.5  (Nov 9, 2015)
minor generic compression improvements

v0.3.4  (Nov 6, 2015)
Faster fast cLevels

v0.3.3  (Nov 5, 2015)
Small compression ratio improvement

v0.3.2  (Nov 2, 2015)
Fixed Visual Studio

v0.3.1  (Nov 2, 2015)
Small compression ratio improvement

v0.3  (Oct 30, 2015)
HC mode : compression levels 2-26

v0.2.2  (Oct 28, 2015)
Fix : Visual Studio 2013 & 2015 release compilation, by Christophe Chevalier

v0.2.1  (Oct 24, 2015)
Fix : Read errors, advanced fuzzer tests, by Hanno Böck

v0.2.0  (Oct 22, 2015)
**Breaking format change**
Faster decompression speed
Can still decode v0.1 format

v0.1.3  (Oct 15, 2015)
fix uninitialization warning, reported by Evan Nemerson

v0.1.2  (Sep 11, 2015)
frame concatenation support

v0.1.1  (Aug 27, 2015)
fix compression bug
detects write-flush errors

v0.1.0  (Aug 25, 2015)
first release