Weekly Check-in: Week of 2026-06-22

[payjoin-bot]

Weekly standup — each contributor has a thread below with auto-gathered activity.

Reply to your thread by end-of-day Monday (your timezone). Copy the template below and fill it in:

### Shipped
<!-- Add anything the bot missed: design work, specs, conversations, off-GitHub contributions. Correct any mistakes. Skip if the bot covered everything. -->

### Focus
What are you working on this week?

### Bottleneck
What is the single biggest bottleneck in progress toward your greater goal?
Name your goal. Name the constraint. Name who or what can unblock it.

Participated: @DanGould, @benalleng, @chavic

[payjoin-bot]

DanGould

@DanGould

Shipped

PRs merged:

• Fix try_preserving_privacy returning Empty when candidates exist

PRs reviewed:

• Expose InputPair previous outpoint over FFI
• Update bitcoind async client 0.14
• Downgrade transitive deps to match minimal direct deps

Issues opened:

• Receiver<Monitor>::check_payment needs rename
• Nit: consider removing "time and tar are" so the comment doesn't go stale, and repeating the uniform comment to all other Cargo.toml files that define package.metadata.cargo-machete for the same reason.

Last Week

Review your previous thread: Last week's thread

Auto-detected signals:

• PR has requested changes: Mailroom fd hygiene

[DanGould]

Shipped

• The try_preserving_privacy fix explicitly unblocked 1.0 and Bull Bitcoin's integration

Focus

• The multiplexing fix needs to get shipped to the infrastructure providers and they need to be legible
• payjoin-cli's 1.0 time is now. I'll be available for review

Bottleneck

I think payjoin-cli checklist and keeping in-flight reviews live across timezones is the thing that bottlenecks progress. Basically individual focus translated to group focus/effort.

[payjoin-bot]

spacebear21

@spacebear21

Shipped

PRs merged:

• Enable HTTP/2 multiplexing on relay-directory hop
• cli: persist sender session after PSBT is created
• chore: update cargo.lock

PRs reviewed:

• Mailroom fd hygiene
• Delegate http tracing to tower middleware

Issues opened:

• Replaying the event log results in "expired" error for successfully completed sessions

Last Week

Review your previous thread: Last week's thread

Auto-detected signals:

• PR awaiting review: chore: update cargo.lock
• PR awaiting review: Rename Monitor method

[payjoin-bot]

benalleng

@benalleng

Shipped

PRs merged:

• Downgrade transitive deps to match minimal direct deps

PRs reviewed:

• Decouple directory poll timing
• Enable HTTP/2 multiplexing on relay-directory hop
• Standardized cargo-machete comments
• Enforce content-length validation on sender and size limits on payjoin-cli
• Mailroom fd hygiene
• cli: persist sender session after PSBT is created
• chore: update cargo.lock

Issues opened:

• No space left on device in runners

Last Week

Review your previous thread: Last week's thread

[benalleng]

Focus

Fully focused on payjoin-cli 1.0 might consider duplicating some long standing open PRs to just get the ball rolling where progress has stalled there.

I also bought a microcontroller to try and test #1615 with more than a few Linux based smoke tests

Bottleneck

Some issue clarification for the network and timing related cli stuff as I really have no domain knowledge there so I am not sure I am the best to give ACKs on any PRs that come up there

[payjoin-bot]

chavic

@chavic

Shipped

PRs reviewed:

• Fixup for name mangling in all-caps acronym identifiers
• Fix try_preserving_privacy returning Empty when candidates exist

Last Week

Review your previous thread: Last week's thread

Auto-detected signals:

• PR awaiting review: Assert bech32 encoding is uppercase
• PR awaiting review: Fix spelling mistakes
• PR awaiting review: Expose InputPair previous outpoint over FFI

[chavic]

Shipped

Opened rust-payjoin:

• Expose InputPair previous outpoint over FFI (draft) — unblocks privacy-preserving selection and reading the settlement amount from the proposal. Expose InputPair outpoint over FFI #1654
• Assert bech32 encoding is uppercase. Assert bech32 encoding is uppercase #1666
• Fix spelling mistakes. Fix spelling mistakes #1665

Open PRs (BTCPay Payjoin plugin, under review):

• Consolidate receiver proposal signature stripping (split out of #59). Sign receiver inputs inside rust-payjoin finalize callback ValeraFinebits/btcpayserver-payjoin-plugin#64
• Check input/output ownership against the wallet and persist seen inputs. Check input/output ownership against the wallet and persist seen inputs ValeraFinebits/btcpayserver-payjoin-plugin#58
• Randomize receiver input selection and consolidate proposal signature stripping. Use rust-payjoin privacy-preserving receiver input selection ValeraFinebits/btcpayserver-payjoin-plugin#59

Reviews (BTCPay Payjoin plugin):

• Update rust-payjoin. Update rust-payjoin ValeraFinebits/btcpayserver-payjoin-plugin#61
• Rename Payjoin to Async Payjoin. feat: Rename Payjoin to Async Payjoin ValeraFinebits/btcpayserver-payjoin-plugin#62

Reviews (uniffi-dart):

• Fixup for name mangling in all-caps acronym identifiers. Fixup for name mangling in all-caps acronym identifiers Uniffi-Dart/uniffi-dart#145

Reviews (rust-payjoin):

• Fix try_preserving_privacy returning Empty when candidates exist. Fix try_preserving_privacy returning Empty when candidates exist #1629

Closed:

• uniffi-bindgen-cs — Upgrade to UniFFI 0.30 and close C# parity gaps in favor of upcoming upgrade. Upgrade to UniFFI 0.30 and close C# parity gaps NordSecurity/uniffi-bindgen-cs#168

Focus

Spend last week correcting the initial fixes in last weeks BTCPay's correctness pass. One merged and two are pending, of which #56 got broken split and narrowed down. This week continues that plan and the backlog.

BTCPay Plugin — finish the correctness pass:

• Finish #58 (whole-wallet ownership + seen-inputs) and #59/#64.
• Get the FFI outpoint exposure shape justification based on BTCPay lessons. Expose InputPair outpoint over FFI #1654
• Credit the observed on-chain settlement output value, not the expected invoice amount.
• Pin the settlement amount from the proposal and validate against the invoice.
• Make the settlement script crash-safe (derive from the committed PSBT on reconciliation).
• Fee estimation from NBXplorer + per-store config. Derive the receiver fee cap from estimation and make it configurable ValeraFinebits/btcpayserver-payjoin-plugin#60
• Decide + document the fallback-broadcast policy.
• Sweep the lows items: OHTTP key TTL, event-log retention, reservation lifetime, change-address churn, non-segwit inputs.

Blockers

• Thinking about the right approach based on integration environment models.

[DanGould]

#1654 is the most critical thing to cover and show, especially because it touches payjoin-1.0 potentially

[payjoin-bot]

zealsham

@zealsham

Shipped

PRs merged:

• Delegate http tracing to tower middleware

Last Week

Review your previous thread: Last week's thread

Auto-detected signals:

• PR has requested changes: OHTTP keys should be rotated

[payjoin-bot]

Mshehu5

@Mshehu5

Shipped

No activity found.

Last Week

Review your previous thread: Last week's thread

[payjoin-bot]

0xZaddyy

@0xZaddyy

Shipped

No activity found.

Last Week

Review your previous thread: Last week's thread

[ValeraFinebits]

Shipped

PRs opened:

• Update rust-payjoin ValeraFinebits/btcpayserver-payjoin-plugin#61
• feat: Rename Payjoin to Async Payjoin ValeraFinebits/btcpayserver-payjoin-plugin#62
• chore: bump version 0.2.3 preview ValeraFinebits/btcpayserver-payjoin-plugin#63
• test: Increase max proposal poll attempts ValeraFinebits/btcpayserver-payjoin-plugin#65
• fix: clarify Async Payjoin checkout mode UI ValeraFinebits/btcpayserver-payjoin-plugin#67

PRs reviewed:

• Sign receiver inputs inside rust-payjoin finalize callback ValeraFinebits/btcpayserver-payjoin-plugin#64

Issues opened:

• Remove temporary NU1903 override from BTCPayServer.Plugins.Payjoin.Tests ValeraFinebits/btcpayserver-payjoin-plugin#66

Focus

• Continue working on the plugin.

[caarloshenriq]

/check-in

[payjoin-bot]

Shipped

PRs merged:

• Update bitcoind async client 0.14

PRs reviewed:

• Fix spelling mistakes
• Add comments to FFI interface
• Mailroom fd hygiene

[caarloshenriq]

Focus

• review PRs
• find a new issue to work

Bottlenack

I'm travelling and using my underpowered laptop

[xstoicunicornx]

/check-in

[payjoin-bot]

Shipped

PRs reviewed:

• Assert bech32 encoding is uppercase
• Fix spelling mistakes
• Bump esbuild and tsx in /payjoin-ffi/javascript

Auto-detected signals:

• PR awaiting review: Add comments to FFI interface
• PR has requested changes: Async Interface for Payjoin Receiver State Machine

[xstoicunicornx]

Focus

• finish refactor for Non-blocking Interface for Payjoin State Machine  #1446
• open issue for ambiguous state when persisting MaybeTerminalSuccessTransition
• update Add comments to FFI interface #1653 to also include updates to the main payjoin crate doc strings to make the doc strings consistent between payjoin-ffi and payjoin crates
• look at Be specific about error handling for methods that don't return state transitions #1422

Bottleneck

None

[bc1cindy]

Shipped

PRs merged:

• fix: Payjoin receiver skips UIH2 avoidance, always contributes unspent[0] cake-tech/cake_wallet#3304

PRs opened:

• Add radix-ness classifier as first step of the radix lower-bound path tx-indexer#85
• Decouple directory poll timing #1658
• Resume v2 polling on transient directory errors #1671
• Document ohttp relay best practice #1547

Issues opened:

• BIP 77: spec the request-timing privacy change #1663
• Retry transient directory errors, and a shared retry policy #1670

PRs reviewed:

• Fund wallets with random coinbase amounts during universe setup tx-indexer#87

Focus

standardizing payjoin fingerprints across integrations (on chain + relay)

• Tracking: relay-observable behavioral fingerprinting #1586
• Tracking: chain-observable transaction-level fingerprinting #1597