PyPI · #1238 most downloaded on PyPI

locust

2.46.613M downloads/molocustio/locust ↗New releases in your daily digest, changelog included.

Developer-friendly load testing framework

Last release 7 days ago
17 Sep 2026
Ships on a steady schedule
a new release about every 2 weeks
Nearly every release is documented
notes for 60 of the last 60 stable releases
1 version withdrawn
withdrawn after publishing
6 years old
1040 releases · first in 2020

Release timeline

1040 releases since 2020

2020202120222023202420252026

20202026

One column per quarter.

Releases

2.40.15 Sept 2025
Pytest plugin: Delay imports to avoid monkey patching until someone uses the fixtures by @cyberw in https://github.com/locustio/locust/pull/3204
What's Changed

Pytest plugin: Delay imports to avoid monkey patching until someone uses the fixtures by @cyberw in https://github.com/locustio/locust/pull/3204

Move pytest plugin to its own directory, to prevent accidental import by @cyberw in https://github.com/locustio/locust/pull/3205

Full Changelog: https://github.com/locustio/locust/compare/2.40.0...2.40.1
Open source →
Additional notes
Full Changelog

Fixed bugs:

2.40.0 with pytest and xdist #3202

Merged pull requests:

Move pytest plugin to its own directory, to prevent accidental import #3205 (cyberw)

Pytest plugin: Delay imports to avoid monkey patching until someone uses the fixtures #3204 (cyberw)
Open source →
Additional notes

Pytest plugin: Delay imports to avoid monkey patching until someone actually uses the fixtures https://github.com/locustio/locust/pull/3204 https://github.com/locustio/locust/pull/3205

2.40.1.dev55 Sept 2025pre-release

Nothing published for this version

2.40.1.dev35 Sept 2025pre-release

Nothing published for this version

2.40.1.dev25 Sept 2025pre-release

Nothing published for this version

2.40.05 Sept 2025

Refactor FastHttpSession to be more like HttpSession by @cyberw in https://github.com/locustio/locust/pull/3198

What's Changed

Refactor FastHttpSession to be more like HttpSession by @cyberw in https://github.com/locustio/locust/pull/3198
Update Dockerfile base to Python 3.13 by @adaamz in https://github.com/locustio/locust/pull/3193
Avoid exception in HttpUser if requests has lost track of the request it made by @cyberw in https://github.com/locustio/locust/pull/3201
Support pytests as locustfiles by @cyberw in https://github.com/locustio/locust/pull/3200

New Contributors

@adaamz made their first contribution in https://github.com/locustio/locust/pull/3193

Full Changelog: https://github.com/locustio/locust/compare/2.39.1...2.40.0

Open source →

Additional notes

Full Changelog

Fixed bugs:

HTTP response 0 #3199

Merged pull requests:

Avoid exception in HttpUser if requests has lost track of the request it made #3201 (cyberw)
Support pytests as locustfiles #3200 (cyberw)
Refactor FastHttpSession to be more like HttpSession #3198 (cyberw)
Update Dockerfile base to Python 3.13 #3193 (adaamz)

Open source →

Additional notes

Add support for pytests as locustfiles https://github.com/locustio/locust/pull/3200
Refactor FastHttpSession slightly https://github.com/locustio/locust/pull/3198
Update Dockerfile base to Python 3.13 https://github.com/locustio/locust/pull/3193

Open source →

2.39.2.dev164 Sept 2025pre-release

Nothing published for this version

2.39.2.dev154 Sept 2025pre-release

Nothing published for this version

2.39.2.dev144 Sept 2025pre-release

Nothing published for this version

2.39.2.dev134 Sept 2025pre-release

Nothing published for this version

2.39.2.dev124 Sept 2025pre-release

Nothing published for this version

2.39.2.dev114 Sept 2025pre-release

Nothing published for this version

2.39.2.dev94 Sept 2025pre-release

Nothing published for this version

2.39.2.dev74 Sept 2025pre-release

Nothing published for this version

2.39.2.dev53 Sept 2025pre-release

Nothing published for this version

2.39.2.dev33 Sept 2025pre-release

Nothing published for this version

2.39.129 Aug 20252 sources agree

Avoid broken gevent version for now by @cyberw in https://github.com/locustio/locust/pull/3196

What's Changed

Avoid broken gevent version for now by @cyberw in https://github.com/locustio/locust/pull/3196

New Contributors

@JumboBear made their first contribution in https://github.com/locustio/locust/pull/3195

Full Changelog: https://github.com/locustio/locust/compare/2.39.0...2.39.1

Open source →

Additional notes

Full Changelog

Merged pull requests:

Avoid broken gevent version for now #3196 (cyberw)
Remove duplicated line in pyproject.toml #3195 (JumboBear)

Open source →

2.39.1.dev1429 Aug 2025pre-release

Nothing published for this version

2.39.1.dev1329 Aug 2025pre-release

Nothing published for this version

2.39.1.dev120 Aug 2025pre-release

Nothing published for this version

2.39.020 Aug 2025

Add MilvusUser and example by @zhuwenxing in https://github.com/locustio/locust/pull/3168

What's Changed

Add MilvusUser and example by @zhuwenxing in https://github.com/locustio/locust/pull/3168
Add SocketIOUser by @cyberw in https://github.com/locustio/locust/pull/3189

New Contributors

@zhuwenxing made their first contribution in https://github.com/locustio/locust/pull/3168

Full Changelog: https://github.com/locustio/locust/compare/2.38.1...2.39.0

Open source →

Additional notes

Full Changelog

Merged pull requests:

Add SocketIOUser #3189 (cyberw)
Add MilvusUser and example #3168 (zhuwenxing)

Open source →

Additional notes

Add MilvusUser https://github.com/locustio/locust/pull/3168
Add SocketIOUser https://github.com/locustio/locust/pull/3189

Open source →

2.38.2.dev2319 Aug 2025pre-release

Nothing published for this version

2.38.2.dev2219 Aug 2025pre-release

Nothing published for this version

2.38.2.dev2119 Aug 2025pre-release

Nothing published for this version

2.38.2.dev718 Aug 2025pre-release

Nothing published for this version

2.38.112 Aug 20252 sources agree

Fix test flakyness and update error message by @amadeuppereira in https://github.com/locustio/locust/pull/3187

What's Changed

Fix test flakyness and update error message by @amadeuppereira in https://github.com/locustio/locust/pull/3187
FastHttpUser: Dont send zstd in Accept-Encoding header by @cyberw in https://github.com/locustio/locust/pull/3188

Full Changelog: https://github.com/locustio/locust/compare/2.38.0...2.38.1

Open source →

Additional notes

Full Changelog

Closed issues:

Support for markov chains to describe a user's behavior #3156
Switch docker base image to one with uv preinstalled #3061

Merged pull requests:

FastHttpUser: Dont send zstd in Accept-Encoding header #3188 (cyberw)
Fix test flakyness and update error message #3187 (amadeuppereira)

Open source →

2.38.1.dev612 Aug 2025pre-release

Nothing published for this version

2.38.1.dev47 Aug 2025pre-release

Nothing published for this version

2.38.07 Aug 2025

Add yarn lint precommit by @cyberw in https://github.com/locustio/locust/pull/3175

What's Changed

Add yarn lint precommit by @cyberw in https://github.com/locustio/locust/pull/3175
Webui: Hide no Host Warning when one is Provided by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3177
Bump form-data from 4.0.0 to 4.0.4 in /locust/webui by @dependabot[bot] in https://github.com/locustio/locust/pull/3179
Support for list based custom arguments by @mickdwyer in https://github.com/locustio/locust/pull/3181
Add MarkovTaskSet by @Matthieu-Beauchamp in https://github.com/locustio/locust/pull/3176
Webui: Fix useSortByField by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3185
Optimize unit tests by @amadeuppereira in https://github.com/locustio/locust/pull/3183

New Contributors

@mickdwyer made their first contribution in https://github.com/locustio/locust/pull/3181
@Matthieu-Beauchamp made their first contribution in https://github.com/locustio/locust/pull/3176

Full Changelog: https://github.com/locustio/locust/compare/2.37.14...2.38.0

Open source →

Additional notes

Full Changelog

Fixed bugs:

Failures table sorting is reset to ascending after a few seconds #3184
argparse.ArgumentError: argument --profile: conflicting option string: --profile (locust==2.37.14) #3180

Merged pull requests:

Webui: Fix useSortByField #3185 (andrewbaldwin44)
Optimize unit tests #3183 (amadeuppereira)
Support for list based custom arguments #3181 (mickdwyer)
Bump form-data from 4.0.0 to 4.0.4 in /locust/webui #3179 (dependabot[bot])
Webui: Hide no Host Warning when one is Provided #3177 (andrewbaldwin44)
Add MarkovTaskSet #3176 (Matthieu-Beauchamp)
Add yarn lint precommit #3175 (cyberw)

Open source →

Additional notes

Add MarkovTaskSet https://github.com/locustio/locust/pull/3176
Support for list based custom arguments https://github.com/locustio/locust/pull/3181
Webui fixes https://github.com/locustio/locust/pull/3177 & https://github.com/locustio/locust/pull/3185

Open source →

2.37.15.dev697 Aug 2025pre-release

Nothing published for this version

2.37.15.dev306 Aug 2025pre-release

Nothing published for this version

2.37.15.dev296 Aug 2025pre-release

Nothing published for this version

2.37.15.dev284 Aug 2025pre-release

Nothing published for this version

2.37.15.dev261 Aug 2025pre-release

Nothing published for this version

2.37.15.dev1226 Jul 2025pre-release

Nothing published for this version

2.37.15.dev922 Jul 2025pre-release

Nothing published for this version

2.37.15.dev722 Jul 2025pre-release

Nothing published for this version

2.37.15.dev518 Jul 2025pre-release

Nothing published for this version

2.37.15.dev418 Jul 2025pre-release

Nothing published for this version

2.37.1416 Jul 2025

Web UI: Improve Locust Cloud Tab by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3172

What's Changed

Web UI: Improve Locust Cloud Tab by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3172
Web UI: Fix Chart Zoom Slider by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3174

Full Changelog: https://github.com/locustio/locust/compare/2.37.13...2.37.14

Open source →

Additional notes

Full Changelog

Merged pull requests:

Web UI: Fix Chart Zoom Slider #3174 (andrewbaldwin44)
Web UI: Improve Locust Cloud Tab #3172 (andrewbaldwin44)

Open source →

Additional notes

Web UI: Fix Chart Zoom Slider https://github.com/locustio/locust/pull/3174

Open source →

2.37.14.dev916 Jul 2025pre-release

Nothing published for this version

2.37.14.dev816 Jul 2025pre-release

Nothing published for this version

2.37.14.dev515 Jul 2025pre-release

Nothing published for this version

2.37.14.dev415 Jul 2025pre-release

Nothing published for this version

2.37.14.dev315 Jul 2025pre-release

Nothing published for this version

2.37.14.dev115 Jul 2025pre-release

Nothing published for this version

2.37.1315 Jul 2025

Web UI: Shrink Bundle Size by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3169

What's Changed

Web UI: Shrink Bundle Size by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3169
Remove safe_name from /stats/requests response by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3171

Full Changelog: https://github.com/locustio/locust/compare/2.37.12...2.37.13

Open source →

Additional notes

Full Changelog

Fixed bugs:

Locust can't install on alpine linux anymore #3166

Closed issues:

Decouple the JavaScript asset code from the report #3064

Merged pull requests:

Remove safe_name from /stats/requests response #3171 (andrewbaldwin44)
Web UI: Shrink Bundle Size #3169 (andrewbaldwin44)

Open source →

Additional notes

Web UI: Shrink Bundle Size by https://github.com/locustio/locust/pull/3169
Remove safe_name from /stats/requests response https://github.com/locustio/locust/pull/3171

Open source →

2.37.13.dev1715 Jul 2025pre-release

Nothing published for this version

2.37.13.dev1314 Jul 2025pre-release

Nothing published for this version

2.37.13.dev1214 Jul 2025pre-release

Nothing published for this version

2.37.13.dev511 Jul 2025pre-release

Nothing published for this version

2.37.13.dev411 Jul 2025pre-release

Nothing published for this version

2.37.13.dev39 Jul 2025pre-release

Nothing published for this version

2.37.13.dev18 Jul 2025pre-release

Nothing published for this version

2.37.128 Jul 20252 sources agree

Bump brace-expansion from 1.1.11 to 1.1.12 in /locust/webui by @dependabot in https://github.com/locustio/locust/pull/3160

What's Changed

Bump brace-expansion from 1.1.11 to 1.1.12 in /locust/webui by @dependabot in https://github.com/locustio/locust/pull/3160
Attempt to increase open file limit (RLIMIT_NOFILE) even on master. by @cyberw in https://github.com/locustio/locust/pull/3162

Full Changelog: https://github.com/locustio/locust/compare/2.37.11...2.37.12

Open source →

Additional notes

Full Changelog

Fixed bugs:

Error shutting down when using processes #3161
1279 Locust instances makes master run at 100% continously #3142

Merged pull requests:

Attempt to increase open file limit (RLIMIT_NOFILE) even on master. #3162 (cyberw)
Bump brace-expansion from 1.1.11 to 1.1.12 in /locust/webui #3160 (dependabot[bot])

Open source →

2.37.12.dev58 Jul 2025pre-release

Nothing published for this version

2.37.12.dev42 Jul 2025pre-release

Nothing published for this version

2.37.12.dev225 Jun 2025pre-release

Nothing published for this version

2.37.1123 Jun 2025

Web UI: Always Warn of Invalid Host by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3155

What's Changed

Web UI: Always Warn of Invalid Host by @andrewbaldwin44 in https://github.com/locustio/locust/pull/3155
Forward locustfiles to locust cloud by @amadeuppereira in https://github.com/locustio/locust/pull/3157 / https://github.com/locustcloud/locust-cloud/pull/38

Full Changelog: https://github.com/locustio/locust/compare/2.37.10...2.37.11

Open source →

Additional notes

Full Changelog

Fixed bugs: