[Silthus]

💡 Motivation and Context

A Python backend that renders its own email can't send it through PostHog today. emails.send takes only a template made in PostHog, by its ID. This PR adds the code form to emails.send, beside the template form from #1093. It matches posthog-node in PostHog/posthog-js#5509. The SDK contract is PostHog/sdk-specs openspec/specs/emails/spec.md, plus the draft change add-emails-code-form.

posthog.emails.send(
    to="[email protected]",
    distinct_id="user_123",
    template_key="password-reset",
    subject="Reset your password",
    html=rendered_html,  # React email: render it to HTML in your app first
)

Moved from Silthus#2. Part of map Silthus/posthog#461.

Caution

Merge risk: medium, one-way door once released. A release makes the new keyword names and the migrated_from client option a public contract.

Do not merge before the server deploys. The code form depends on the code arm of send/email/ in PostHog/posthog #127122 and #127123. Until both deploy, a code send gets a 400. Merge and release this after them.

Changes:

• Two forms, one send, typed with Unpack and one @overload each, on Emails and AsyncEmails. A mix of the two forms raises TypeError before any request.
• Rendered content posts a flat body to POST /messaging/send/email/: template_key, subject, html and/or text, and a flat distinct_id, as master's flat body (feat: send a flat body from emails.send #1155) has it.
• Engagement capture belongs to the code form, True by default. The template form refuses it.
• The code form also takes from_, reply_to and max_retries. migrated_from is a client option. None counts as left out.
• Out of scope for now: local templates (template_data on a code send, the content hash, the upload by key), cc, bcc, headers, tags and attachments. A code send with any of them raises TypeError.

💚 How did you test it?

Test seams: Emails.send and AsyncEmails.send on a real client with the HTTP transport faked, and .github/scripts/check_strict_types.sh under pyright strict. The tests pin each code-form body and each refusal, including the parked fields.

Proof at b93ea5c, through fleet proof (the gate passes):

• Live run: code sends and template sends from posthog-python against the server code send at 20fad8c, delivered into a mail catcher. At b93ea5c, a code send with reply_to=[] is accepted and delivered, and the old body with reply_to: [] gets a 400.
• Cross-version: this head and the released SDK against master's server, a server with old CDP pods, and the PR server. Master's server answers a code send with a 400.
• Shadow diff: request bodies and results at main and at this head, each difference classified as intended.
• Production shape: the SDK reads no stored data; the server's sender inputs are measured on #127123.

📝 Checklist

• All commits are signed (see Commit signing)
• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

If releasing new changes

• Ran sampo add to generate a changeset file

🤖 Agent context

Autonomy: Human-driven (agent-assisted)

• Written by Claude Code, Claude Opus 5.5 (claude-opus-5-5), as lane sdk3 of map Map: send code-managed email templates with one PostHog call Silthus/posthog#461, directed by Michael.
• e654aef merges main with the flat body. 20fad8c cuts the local-template form and the extra fields, per Michael's scope cut. 9a4dd48 adds tests for the async code-form send and migrated_from. b93ea5c leaves an empty reply_to list out of the body, because the server refuses one.
• Reviews: on the fork, a GPT-6.1 Sol full read, then a QA swarm with GPT-6.1 Sol and Claude Opus 5.5 fresh eyes. Here, GPT-6.1 Sol reads of the cut, the last a final read at b93ea5c.
• Decisions: from_ names from; distinct_id is flat in both forms; argument errors stay TypeError and ValueError, as 7.81.0 has them; local templates and the extra fields wait for their server slice.

🤖 Generated with Claude Code

[github-actions]

posthog-python Compliance Report

Date: 2026-11-05T11:05:05.680101+00:00
Duration: 260157ms

✅ All Tests Passed!

121/121 tests passed

---

Capture_V1 Tests

✅ 95/95 tests passed

View Details

Test	Status	Duration
Endpoint And Method.Targets V1 Endpoint	✅	517ms
Endpoint And Method.Does Not Use Legacy Endpoints	✅	512ms
Required Headers.Has Authorization Bearer Header	✅	513ms
Required Headers.Has Content Type Json	✅	512ms
Required Headers.Has Posthog Sdk Info Format	✅	512ms
Required Headers.Has Posthog Attempt Header	✅	512ms
Required Headers.Has Posthog Request Id	✅	511ms
Required Headers.Has Posthog Request Timestamp	✅	512ms
Required Headers.Has User Agent	✅	512ms
Body Format.Body Has Created At And Batch	✅	512ms
Body Format.No Api Key In Body	✅	511ms
Body Format.No Sent At In Body	✅	512ms
Event Format.Event Has Required Root Fields	✅	512ms
Event Format.Event Uuid Is Valid	✅	512ms
Event Format.Event Timestamp Is Rfc3339	✅	513ms
Event Format.Non Utc Event Timestamp Is Converted To Utc	✅	527ms
Event Format.Distinct Id Is String	✅	512ms
Event Format.Distinct Id At Root Not Properties	✅	512ms
Event Format.Custom Properties Preserved	✅	512ms
Event Format.Set Properties Preserved	✅	511ms
Event Format.Set Once Properties Preserved	✅	513ms
Event Format.Groups Properties Preserved	✅	512ms
Event Format.Sdk Generates Uuid If Not Provided	✅	512ms
Event Format.Event Has Required Root Fields Batch	✅	515ms
Event Format.Event Uuid Is Valid Batch	✅	515ms
Event Format.Event Timestamp Is Rfc3339 Batch	✅	516ms
Event Format.Distinct Id Is String Batch	✅	514ms
Event Format.Distinct Id At Root Not Properties Batch	✅	515ms
Event Format.Custom Properties Preserved Batch	✅	516ms
Event Format.Set Properties Preserved Batch	✅	515ms
Event Format.Set Once Properties Preserved Batch	✅	516ms
Event Format.Groups Properties Preserved Batch	✅	515ms
Event Format.Sdk Generates Uuid If Not Provided Batch	✅	515ms
Batch Behavior.Multiple Events In Single Batch	✅	519ms
Batch Behavior.Batch Envelope Smoke	✅	518ms
Batch Behavior.Flush With No Events Sends Nothing	✅	509ms
Batch Behavior.Flush At Triggers Batch	✅	1013ms
Batch Behavior.Created At Reflects Batch Creation Time	✅	512ms
Deduplication.Generates Unique Uuids	✅	519ms
Deduplication.Different Events Same Content Different Uuids	✅	513ms
Deduplication.Preserves Uuid On Retry	✅	6521ms
Deduplication.Preserves Timestamp On Retry	✅	6522ms
Deduplication.Preserves Uuid And Timestamp On Batch Retry	✅	6525ms
Deduplication.No Duplicate Events In Batch	✅	521ms
Header Behavior On Retry.Attempt Header Starts At One	✅	512ms
Header Behavior On Retry.Attempt Header Increments On Retry	✅	13522ms
Header Behavior On Retry.Request Id Preserved On Retry	✅	6519ms
Header Behavior On Retry.Different Requests Have Different Request Ids	✅	3022ms
Header Behavior On Retry.Request Timestamp Changes On Retry	✅	6521ms
Response Format Validation.Success Response Has Uuid Keyed Results	✅	512ms
Response Format Validation.Success Response Has Ok For Each Event	✅	516ms
Response Format Validation.Success No Retry After When All Ok	✅	513ms
Response Format Validation.Success Retry After Present When Retry Events	✅	1518ms
Response Format Validation.Success No Retry After When Drop Only	✅	514ms
Response Format Validation.Response Echoes Request Id	✅	512ms
Retry Behavior.Retries On 408	✅	6519ms
Retry Behavior.Retries On 500	✅	6517ms
Retry Behavior.Retries On 503	✅	8525ms
Retry Behavior.Retries On 504	✅	6521ms
Retry Behavior.Retryable Errors Have Retry After	✅	3517ms
Retry Behavior.Respects Retry After On Retryable Error	✅	11523ms
Retry Behavior.Does Not Retry On 400	✅	2515ms
Retry Behavior.Does Not Retry On 401	✅	2515ms
Retry Behavior.Does Not Retry On 402	✅	2515ms
Retry Behavior.Does Not Retry On 413	✅	2514ms
Retry Behavior.Does Not Retry On 415	✅	2515ms
Retry Behavior.Non Retryable Errors Have No Retry After	✅	2515ms
Retry Behavior.Implements Backoff	✅	22536ms
Retry Behavior.Max Retries Respected	✅	22539ms
Partial Batch Handling.Handles 200 Full Success	✅	2514ms
Partial Batch Handling.Handles 200 With All Ok	✅	3518ms
Partial Batch Handling.Does Not Retry Dropped Events	✅	3518ms
Partial Batch Handling.Does Not Retry Limited Events	✅	3517ms
Partial Batch Handling.Prunes Ok Events On Partial Retry	✅	6521ms
Partial Batch Handling.Prunes Dropped Events On Partial Retry	✅	6523ms
Partial Batch Handling.Retries Only Retry Events From Partial	✅	6520ms
Partial Batch Handling.Partial Retry Preserves Uuids	✅	6522ms
Partial Batch Handling.Partial Retry Attempt Header Increments	✅	6520ms
Partial Batch Handling.Partial Retry Request Id Preserved	✅	6522ms
Partial Batch Handling.Respects Retry After On Partial	✅	8523ms
Partial Batch Handling.Unknown Result Treated As Terminal	✅	3517ms
Partial Batch Handling.Mixed Ok Drop Limited No Retry	✅	3520ms
Compression.Sends Gzip Content Encoding	✅	512ms
Compression.No Content Encoding When Disabled	✅	512ms
Compression.Compressed Body Is Decompressible	✅	511ms
Error Handling.Does Not Retry On Unknown 4Xx	✅	2513ms
Event Options.Cookieless Mode Override	✅	512ms
Event Options.Disable Skew Correction Override	✅	511ms
Event Options.Process Person Profile Override	✅	511ms
Event Options.Product Tour Id Override	✅	512ms
Event Options.Unset Options Omitted	✅	511ms
Event Options.Options Override In Batch	✅	514ms
Geoip And Historical Migration.Geoip Disable Injected Into Properties	✅	512ms
Geoip And Historical Migration.Historical Migration Set In Body	✅	512ms
Geoip And Historical Migration.Historical Migration Absent By Default	✅	512ms

Capture_Ai Tests

✅ 5/5 tests passed

View Details

Test	Status	Duration
Routing.Capture Ai Posts To Ai Endpoint	✅	512ms
Routing.Capture Does Not Reroute Ai Named Events	✅	511ms
Identity.Capture Ai Event Has Uuid	✅	511ms
Identity.Capture Ai Keeps Supplied Uuid	✅	512ms
Timestamp Format.Non Utc Event Timestamp Is Converted To Utc	✅	511ms

Feature_Flags Tests

✅ 17/17 tests passed

View Details

Test	Status	Duration
Request Payload.Request With Person Properties Device Id	✅	13ms
Request Payload.Flags Request Uses V4 Query Param	✅	9ms
Request Payload.Flags Request Hits Flags Path Not Decide	✅	10ms
Request Payload.Flags Request Omits Authorization Header	✅	9ms
Request Payload.Token In Flags Body Matches Init	✅	9ms
Request Payload.Groups Round Trip	✅	10ms
Request Payload.Groups Default To Empty Object	✅	9ms
Request Payload.Disable Geoip False Propagates As Geoip Disable False	✅	10ms
Request Payload.Disable Geoip Omitted Defaults To False	✅	10ms
Request Payload.Flag Keys To Evaluate Contains Only Requested Key	✅	9ms
Request Lifecycle.No Flags Request On Init Alone	✅	4ms
Request Lifecycle.No Flags Request On Normal Capture	✅	509ms
Request Lifecycle.Two Flag Calls Produce Two Remote Requests	✅	16ms
Request Lifecycle.Mock Response Value Is Returned To Caller	✅	10ms
Retry Behavior.Retries Flags On 502	✅	314ms
Retry Behavior.Retries Flags On 504	✅	315ms
Side Effect Events.Get Feature Flag Captures Feature Flag Called Event	✅	513ms

Feature_Flags_Local_Evaluation Tests

✅ 4/4 tests passed

View Details

Test	Status	Duration
Versioned Boolean Matching.Matching Version Missing	✅	69ms
Versioned Boolean Matching.Matching Version 1	✅	64ms
Versioned Boolean Matching.Matching Version 2	✅	64ms
Versioned Boolean Matching.Version Only Reload 1 2 1 2 Missing	✅	37ms

[posthog]

PostHog Review · Standard · reviewed 9a4dd48: 1 Should fix.

See this review and its findings in PostHog Review. Comment @posthog review --deep for a Deep review. A Deep review takes longer and looks deeper than a Standard review.

[marandaneto]

The code looks good; no qualifying findings. Verdict: correct.

[github-actions]

SDK performance: posthog-python

Benchmarks completed. No changes flagged for review.

Flags require at least a 5% change in the median and all six pairs agreeing on direction. This is a noise filter, not proof of a performance change or a CI gate.

View all results

Test	Measurement	Before PR	With PR	Change	Assessment
Capture and deliver events (32-byte payload, burst) Shard: capture	Managed heap after settling	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​; head:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Managed heap after settling	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​; head:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​
Capture and deliver events (32-byte payload, steady) Shard: capture	Managed heap after settling	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​; head:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Managed heap after settling	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​; head:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​
Queue an event (32-byte payload) Shard: capture	Allocated memory per operation	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​; head:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​
Queue an event (32-byte payload) Shard: capture	Allocations per operation	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​; head:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​
Queue an event (4,096-byte payload) Shard: capture	Allocated memory per operation	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​; head:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​
Queue an event (4,096-byte payload) Shard: capture	Allocations per operation	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​; head:​ Background preparation has no public completion boundary before flush; see capture.​drain for full-pipeline allocations.​
Evaluate 1,000 flags under concurrent load Shard: flags-memory	Managed heap after settling	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​; head:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​
Refresh 1,000 flag definitions Shard: flags-memory	Managed heap after settling	—	—	—	unavailable; base:​ unsupported; head:​ unsupported; base:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​; head:​ CPython has no uninstrumented total managed-heap byte counter; tracing would distort this RSS pass.​
Capture and deliver events (32-byte payload, burst) Shard: capture	Allocated memory per operation	113.54 KiB/op	113.54 KiB/op	<0.1% less memory	Not flagged
Capture and deliver events (32-byte payload, burst) Shard: capture	Allocations per operation	1,096.59 count/op	1,096.57 count/op	<0.1% fewer	Not flagged
Capture and deliver events (32-byte payload, burst) Shard: capture	Time per operation	50.3 µs/op	50.4 µs/op	0.2% more time	Not flagged
Capture and deliver events (32-byte payload, burst) Shard: capture	Idle process memory (RSS)	35.98 MiB	36.02 MiB	0.1% more memory	Not flagged
Capture and deliver events (32-byte payload, burst) Shard: capture	Observed peak process memory (RSS)	37.73 MiB	37.76 MiB	<0.1% more memory	Not flagged
Capture and deliver events (32-byte payload, burst) Shard: capture	Process memory after settling (RSS)	37.73 MiB	37.76 MiB	<0.1% more memory	Not flagged
Capture and deliver events (32-byte payload, burst) Shard: capture	Process CPU time per operation	51.56 µs/op	51.4 µs/op	0.3% less time	Not flagged
Capture and deliver events (32-byte payload, burst) Shard: capture	Lifetime peak process memory (RSS)	40.21 MiB	40.21 MiB	No observed change	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Allocated memory per operation	166.1 KiB/op	166.1 KiB/op	<0.1% more memory	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Allocations per operation	1,089.57 count/op	1,089.58 count/op	<0.1% more	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Time per operation	71.45 µs/op	70.92 µs/op	0.8% less time	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Idle process memory (RSS)	40.77 MiB	40.81 MiB	<0.1% more memory	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Observed peak process memory (RSS)	45.87 MiB	45.91 MiB	<0.1% more memory	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Process memory after settling (RSS)	45.88 MiB	45.91 MiB	<0.1% more memory	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Process CPU time per operation	67.29 µs/op	66.1 µs/op	1.8% less time	Not flagged
Capture and deliver events (4,096-byte payload, burst) Shard: capture	Lifetime peak process memory (RSS)	50.62 MiB	50.81 MiB	0.4% more memory	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Allocated memory per operation	117.68 KiB/op	117.68 KiB/op	<0.1% less memory	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Allocations per operation	1,136.6 count/op	1,136.58 count/op	<0.1% fewer	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Time per operation	60.82 µs/op	58.69 µs/op	3.5% less time	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Idle process memory (RSS)	35.77 MiB	35.99 MiB	0.6% more memory	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Observed peak process memory (RSS)	35.89 MiB	36.09 MiB	0.6% more memory	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Process memory after settling (RSS)	35.89 MiB	36.09 MiB	0.6% more memory	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Process CPU time per operation	60.91 µs/op	58.54 µs/op	3.9% less time	Not flagged
Capture and deliver events (32-byte payload, steady) Shard: capture	Lifetime peak process memory (RSS)	40.21 MiB	40.21 MiB	No observed change	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Allocated memory per operation	170.57 KiB/op	170.57 KiB/op	<0.1% more memory	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Allocations per operation	1,129.45 count/op	1,129.45 count/op	<0.1% fewer	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Time per operation	74.91 µs/op	77.53 µs/op	3.5% more time	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Idle process memory (RSS)	40.65 MiB	40.66 MiB	<0.1% more memory	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Observed peak process memory (RSS)	40.67 MiB	40.66 MiB	<0.1% less memory	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Process memory after settling (RSS)	40.67 MiB	40.66 MiB	<0.1% less memory	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Process CPU time per operation	71.84 µs/op	75.37 µs/op	4.9% more time	Not flagged
Capture and deliver events (4,096-byte payload, steady) Shard: capture	Lifetime peak process memory (RSS)	40.93 MiB	40.93 MiB	<0.1% less memory	Not flagged
Queue an event (32-byte payload) Shard: capture	Caller-thread CPU time per operation	38.17 µs/op	36.35 µs/op	4.8% less time	Not flagged
Queue an event (32-byte payload) Shard: capture	Time per operation	38.17 µs/op	36.35 µs/op	4.8% less time	Not flagged
Queue an event (4,096-byte payload) Shard: capture	Caller-thread CPU time per operation	36.39 µs/op	34.02 µs/op	6.5% less time	Not flagged
Queue an event (4,096-byte payload) Shard: capture	Time per operation	36.39 µs/op	35.6 µs/op	2.2% less time	Not flagged
Evaluate all 10 flags Shard: flags-scaling	Allocated memory per operation	200.98 KiB/op	200.98 KiB/op	No observed change	Not flagged
Evaluate all 10 flags Shard: flags-scaling	Allocations per operation	2,339.33 count/op	2,339.33 count/op	No observed change	Not flagged
Evaluate all 10 flags Shard: flags-scaling	Time per operation	88.11 µs/op	87.97 µs/op	0.2% less time	Not flagged
Evaluate all 10 flags Shard: flags-scaling	Process CPU time per operation	88.11 µs/op	87.97 µs/op	0.2% less time	Not flagged
Evaluate all 100 flags Shard: flags-scaling	Allocated memory per operation	1.93 MiB/op	1.93 MiB/op	No observed change	Not flagged
Evaluate all 100 flags Shard: flags-scaling	Allocations per operation	23,013.56 count/op	23,013.56 count/op	No observed change	Not flagged
Evaluate all 100 flags Shard: flags-scaling	Time per operation	858.78 µs/op	858.74 µs/op	<0.1% less time	Not flagged
Evaluate all 100 flags Shard: flags-scaling	Process CPU time per operation	858.82 µs/op	858.77 µs/op	<0.1% less time	Not flagged
Evaluate all 1,000 flags Shard: flags-scaling	Allocated memory per operation	19.24 MiB/op	19.24 MiB/op	No observed change	Not flagged
Evaluate all 1,000 flags Shard: flags-scaling	Allocations per operation	229,654.94 count/op	229,654.94 count/op	No observed change	Not flagged
Evaluate all 1,000 flags Shard: flags-scaling	Time per operation	8.63 ms/op	8.54 ms/op	1% less time	Not flagged
Evaluate all 1,000 flags Shard: flags-scaling	Process CPU time per operation	8.63 ms/op	8.54 ms/op	1% less time	Not flagged
Evaluate 1,000 flags under concurrent load Shard: flags-memory	Idle process memory (RSS)	42.32 MiB	41.6 MiB	1.7% less memory	Not flagged
Evaluate 1,000 flags under concurrent load Shard: flags-memory	Observed peak process memory (RSS)	42.61 MiB	41.95 MiB	1.5% less memory	Not flagged
Evaluate 1,000 flags under concurrent load Shard: flags-memory	Process memory after settling (RSS)	42.61 MiB	41.95 MiB	1.5% less memory	Not flagged
Evaluate 1,000 flags under concurrent load Shard: flags-memory	Lifetime peak process memory (RSS)	42.39 MiB	42.46 MiB	0.2% more memory	Not flagged
Refresh 1,000 flag definitions Shard: flags-memory	Idle process memory (RSS)	42.1 MiB	41.45 MiB	1.5% less memory	Not flagged
Refresh 1,000 flag definitions Shard: flags-memory	Observed peak process memory (RSS)	42.2 MiB	42.17 MiB	<0.1% less memory	Not flagged
Refresh 1,000 flag definitions Shard: flags-memory	Process memory after settling (RSS)	41.89 MiB	42.1 MiB	0.5% more memory	Not flagged
Refresh 1,000 flag definitions Shard: flags-memory	Lifetime peak process memory (RSS)	42.6 MiB	42.51 MiB	0.2% less memory	Not flagged
Evaluate one boolean flag Shard: flags-single	Allocated memory per operation	15.05 KiB/op	15.05 KiB/op	No observed change	Not flagged
Evaluate one boolean flag Shard: flags-single	Allocations per operation	173.76 count/op	173.76 count/op	No observed change	Not flagged
Evaluate one boolean flag Shard: flags-single	Time per operation	13.89 µs/op	13.87 µs/op	<0.1% less time	Not flagged
Evaluate one boolean flag Shard: flags-single	Process CPU time per operation	13.89 µs/op	13.87 µs/op	<0.1% less time	Not flagged
Evaluate a cohort-filtered flag Shard: flags-single	Allocated memory per operation	23.12 KiB/op	23.12 KiB/op	No observed change	Not flagged
Evaluate a cohort-filtered flag Shard: flags-single	Allocations per operation	270.27 count/op	270.27 count/op	No observed change	Not flagged
Evaluate a cohort-filtered flag Shard: flags-single	Time per operation	21.79 µs/op	21.43 µs/op	1.7% less time	Not flagged
Evaluate a cohort-filtered flag Shard: flags-single	Process CPU time per operation	21.79 µs/op	21.43 µs/op	1.7% less time	Not flagged
Evaluate a flag (early match) Shard: flags-single	Allocated memory per operation	35.71 KiB/op	35.71 KiB/op	No observed change	Not flagged
Evaluate a flag (early match) Shard: flags-single	Allocations per operation	387.27 count/op	387.27 count/op	No observed change	Not flagged
Evaluate a flag (early match) Shard: flags-single	Time per operation	27.8 µs/op	27.61 µs/op	0.7% less time	Not flagged
Evaluate a flag (early match) Shard: flags-single	Process CPU time per operation	27.8 µs/op	27.61 µs/op	0.7% less time	Not flagged
Evaluate a flag (late match) Shard: flags-single	Allocated memory per operation	53.59 KiB/op	53.59 KiB/op	No observed change	Not flagged
Evaluate a flag (late match) Shard: flags-single	Allocations per operation	576.27 count/op	576.27 count/op	No observed change	Not flagged
Evaluate a flag (late match) Shard: flags-single	Time per operation	38.46 µs/op	38.1 µs/op	0.9% less time	Not flagged
Evaluate a flag (late match) Shard: flags-single	Process CPU time per operation	38.46 µs/op	38.1 µs/op	0.9% less time	Not flagged
Evaluate a flag (no match) Shard: flags-single	Allocated memory per operation	52.14 KiB/op	52.14 KiB/op	No observed change	Not flagged
Evaluate a flag (no match) Shard: flags-single	Allocations per operation	556.77 count/op	556.77 count/op	No observed change	Not flagged
Evaluate a flag (no match) Shard: flags-single	Time per operation	34.88 µs/op	34.71 µs/op	0.5% less time	Not flagged
Evaluate a flag (no match) Shard: flags-single	Process CPU time per operation	34.88 µs/op	34.71 µs/op	0.5% less time	Not flagged
Evaluate a property-filtered flag Shard: flags-single	Allocated memory per operation	17.84 KiB/op	17.84 KiB/op	No observed change	Not flagged
Evaluate a property-filtered flag Shard: flags-single	Allocations per operation	198.27 count/op	198.27 count/op	No observed change	Not flagged
Evaluate a property-filtered flag Shard: flags-single	Time per operation	16.49 µs/op	16.61 µs/op	0.7% more time	Not flagged
Evaluate a property-filtered flag Shard: flags-single	Process CPU time per operation	16.49 µs/op	16.61 µs/op	0.7% more time	Not flagged
Evaluate a regex-filtered flag Shard: flags-single	Allocated memory per operation	19.23 KiB/op	19.23 KiB/op	No observed change	Not flagged
Evaluate a regex-filtered flag Shard: flags-single	Allocations per operation	210.77 count/op	210.77 count/op	No observed change	Not flagged
Evaluate a regex-filtered flag Shard: flags-single	Time per operation	17.17 µs/op	17.37 µs/op	1.2% more time	Not flagged
Evaluate a regex-filtered flag Shard: flags-single	Process CPU time per operation	17.17 µs/op	17.37 µs/op	1.2% more time	Not flagged
Evaluate a rollout flag Shard: flags-single	Allocated memory per operation	14.04 KiB/op	14.04 KiB/op	No observed change	Not flagged
Evaluate a rollout flag Shard: flags-single	Allocations per operation	160.76 count/op	160.76 count/op	No observed change	Not flagged
Evaluate a rollout flag Shard: flags-single	Time per operation	12.93 µs/op	12.98 µs/op	0.4% more time	Not flagged
Evaluate a rollout flag Shard: flags-single	Process CPU time per operation	12.93 µs/op	12.98 µs/op	0.4% more time	Not flagged
Evaluate a multivariate flag Shard: flags-single	Allocated memory per operation	15.21 KiB/op	15.21 KiB/op	No observed change	Not flagged
Evaluate a multivariate flag Shard: flags-single	Allocations per operation	177.77 count/op	177.77 count/op	No observed change	Not flagged
Evaluate a multivariate flag Shard: flags-single	Time per operation	14.54 µs/op	14.52 µs/op	0.2% less time	Not flagged
Evaluate a multivariate flag Shard: flags-single	Process CPU time per operation	14.54 µs/op	14.52 µs/op	0.2% less time	Not flagged

Values are medians of paired measurements. Not flagged does not mean unchanged. Unavailable means a measurement could not be provided, not zero. Estimated allocation measurements retain their instrumentation uncertainty. RSS measures the whole process, not just SDK allocations; observed peaks are sampled checkpoints. Paired ranges in the diagnostics describe variability, not confidence intervals.

Each shard uses its own runner; compare Before PR against With PR within a row, not across shards.

Compared db52a785f2d40f6813f25309fd2a7ea3e28aa59a → 268c59b2e2e172e1dff7115839f5c4c5f1f18b29.

Full report and diagnostics

102 metric rows; 102 rows shown in all results. Omitted or shortened data remain in comparison.json, including per-runner environments, resource limits, measurement methods, samples and checkpoints.