- JSON-RPC: `multiwithdraw` command to batch multiple onchain sends in a single transaction. Note it shuffles inputs and outputs, does not use BIP69. ([3812](https://github.com/ElementsProject/lightning/pull/3812))
- JSON-RPC: `multifundchannel` command to fund multiple channels to different peers all in a single onchain transaction. ([3763](https://github.com/ElementsProject/lightning/pull/3763))
- JSON-RPC: `delpay` command to delete a payment once completed or failed. ([3899](https://github.com/ElementsProject/lightning/pull/3899))
- JSON-RPC: `listpays` can be used to query payments using the `payment_hash` ([3888](https://github.com/ElementsProject/lightning/pull/3888))
- JSON-RPC: `listpays` now includes the `payment_hash` ([3888](https://github.com/ElementsProject/lightning/pull/3888))
- JSON-RPC: `listpays` now includes the timestamp of the first part of the payment ([3909](https://github.com/ElementsProject/lightning/pull/3909))
- Build: New reproducible build system now uses docker: try it at home with `doc/REPRODUCIBLE.md`! ([4021](https://github.com/ElementsProject/lightning/pull/4021))
- Plugins: Proxy information now provided in `init.configuration`. ([4010](https://github.com/ElementsProject/lightning/pull/4010))
- Plugins: `openchannel_hook` is now chainable ([3960](https://github.com/ElementsProject/lightning/pull/3960))
- JSON-RPC: `listpeers` shows `features` list for each channel. ([3963](https://github.com/ElementsProject/lightning/pull/3963))
- JSON-RPC: `signpsbt` takes an optional `signonly` array to limit what inputs to sign. ([3954](https://github.com/ElementsProject/lightning/pull/3954))
- JSON-RPC: `utxopsbt` takes a new `locktime` parameter ([3954](https://github.com/ElementsProject/lightning/pull/3954))
- JSON-RPC: `fundpsbt` takes a new `locktime` parameter ([3954](https://github.com/ElementsProject/lightning/pull/3954))
- JSON-RPC: New low-level command `utxopsbt` to create PSBT from existing utxos. ([3845](https://github.com/ElementsProject/lightning/pull/3845))
- JSON-RPC: `listfunds` now has a `redeemscript` field for p2sh-wrapped outputs. ([3844](https://github.com/ElementsProject/lightning/pull/3844))
- JSON-RPC: `fundchannel` has new `outnum` field indicating which output of the transaction funds the channel. ([3844](https://github.com/ElementsProject/lightning/pull/3844))
- pyln-client: commands and options can now mark themselves deprecated. ([3883](https://github.com/ElementsProject/lightning/pull/3883))
- Plugins: can now mark their options and commands deprecated. ([3883](https://github.com/ElementsProject/lightning/pull/3883))
- plugins: `getmanifest` may now include "allow-deprecated-apis" boolean flag. ([3883](https://github.com/ElementsProject/lightning/pull/3883))
- JSON-RPC: `listpays` now lists the `destination` if it was provided (e.g., via the `pay` plugin or `keysend` plugin) ([3888](https://github.com/ElementsProject/lightning/pull/3888))
- config: New option `--important-plugin` loads a plugin is so important that if it dies, `lightningd` will exit rather than continue. You can still `--disable-plugin` it, however, which trumps `--important-plugin` and it will not be started at all. ([3890](https://github.com/ElementsProject/lightning/pull/3890))
- Plugins: We now explicitly check at startup that our default Bitcoin backend (bitcoind) does relay transactions. ([3889](https://github.com/ElementsProject/lightning/pull/3889))
- Plugins: We now explicitly check at startup the version of our default Bitcoin backend (bitcoind). ([3889](https://github.com/ElementsProject/lightning/pull/3889))
### Changed
- Build: we no longer require extra Python modules to build. ([3994](https://github.com/ElementsProject/lightning/pull/3994))
- Build: SQLite3 is no longer a hard build requirement. C-Lightning can now be built to support only the PostgreSQL back-end. ([3999](https://github.com/ElementsProject/lightning/pull/3999))
- gossipd: The `gossipd` is now a lot quieter, and will log only when a message changed our network topology. ([3981](https://github.com/ElementsProject/lightning/pull/3981))
- Protocol: We now make MPP-aware routehints in invoices. ([3913](https://github.com/ElementsProject/lightning/pull/3913))
- onchaind: We now scorch the earth on theft attempts, RBFing up our penalty transaction as blocks arrive without a penalty transaction getting confirmed. ([3870](https://github.com/ElementsProject/lightning/pull/3870))
- Protocol: `fundchannel` now shuffles inputs and outputs, and no longer follows BIP69. ([3769](https://github.com/ElementsProject/lightning/pull/3769))
- JSON-RPC: `withdraw` now randomizes input and output order, not BIP69. ([3867](https://github.com/ElementsProject/lightning/pull/3867))
- JSON-RPC: `txprepare` reservations stay across restarts: use `fundpsbt`/`reservepsbt`/`unreservepsbt` ([3867](https://github.com/ElementsProject/lightning/pull/3867))
- config: `min-capacity-sat` is now stricter about checking usable capacity of channels. ([3969](https://github.com/ElementsProject/lightning/pull/3969))
- Protocol: Ignore (and log as "unusual") repeated `WIRE_CHANNEL_REESTABLISH` messages, to be compatible with buggy peer software that sometimes does this. ([3964](https://github.com/ElementsProject/lightning/pull/3964))
- contrib: startup_regtest.sh `startup_ln` now takes a number of nodes to create as a parameter ([3992](https://github.com/ElementsProject/lightning/pull/3992))
- JSON-RPC: `invoice` no longer accepts zero amounts (did you mean "any"?) ([3974](https://github.com/ElementsProject/lightning/pull/3974))
- Protocol: channels now pruned after two weeks unless both peers refresh it (see lightning-rfc#767) ([3959](https://github.com/ElementsProject/lightning/pull/3959))
- Protocol: bolt11 invoices always include CLTV fields (see lightning-rfc#785) ([3959](https://github.com/ElementsProject/lightning/pull/3959))
- config: the default CLTV expiry is now 34 blocks, and final expiry 18 blocks as per new BOLT recommendations. ([3959](https://github.com/ElementsProject/lightning/pull/3959))
- Plugins: Builtin plugins are now marked as important, and if they crash, will cause C-lightning to stop as well. ([3890](https://github.com/ElementsProject/lightning/pull/3890))
- Protocol: Funding timeout is now based on the header count reported by the bitcoin backend instead of our current blockheight which might be lower. ([3897](https://github.com/ElementsProject/lightning/pull/3897))
- JSON-RPC: `delinvoice` will now report specific error codes: 905 for failing to find the invoice, 906 for the invoice status not matching the parameter. ([3853](https://github.com/ElementsProject/lightning/pull/3853))
### Deprecated
Note: You should always set `allow-deprecated-apis=false` to test for changes.
- Plugins: `bcli` replacements should note that `sendrawtransaction` now has a second required Boolean argument, `allowhighfees`, which if `true`, means ignore any fee limits and just broadcast the transaction. ([3870](https://github.com/ElementsProject/lightning/pull/3870))
- JSON-RPC: `listsendpays` will no longer add `null` if we don't know the `amount_msat` for a payment. ([3883](https://github.com/ElementsProject/lightning/pull/3883))
- Plugins: `getmanifest` without any parameters; plugins should accept any parameters for future use. ([3883](https://github.com/ElementsProject/lightning/pull/3883))
### Removed
- JSON-RPC: txprepare `destination``satoshi` argument form removed (deprecated v0.7.3) ([3867](https://github.com/ElementsProject/lightning/pull/3867))
### Fixed
- Plugins: `pay``presplit` modifier now supports large payments without exhausting the available HTLCs. ([3986](https://github.com/ElementsProject/lightning/pull/3986))
- Plugins: `pay` corrects a case where we put the sub-payment value instead of the *total* value in the `total_msat` field of a multi-part payment. ([3914](https://github.com/ElementsProject/lightning/pull/3914))
- Plugins: `pay` is less aggressive with forgetting routehints. ([3914](https://github.com/ElementsProject/lightning/pull/3914))
- Plugins: `pay` no longer ignores routehints if the payment exceeds 10,000 satoshi. This is particularly bad if the payee is only reachable via routehints in an invoice. ([3908](https://github.com/ElementsProject/lightning/pull/3908))
- Plugins: `pay` limits the number of splits if the payee seems to have a low number of channels that can enter it, given the max-concurrent-htlcs limit. ([3936](https://github.com/ElementsProject/lightning/pull/3936))
- Plugins: `pay` will now make reliable multi-part payments to nodes it doesn't have a node_announcement for. ([4035](https://github.com/ElementsProject/lightning/pull/4035))
- JSON-RPC: significant speedups for plugins which create large JSON replies (e.g. listpays on large nodes). ([3957](https://github.com/ElementsProject/lightning/pull/3957))
- doc: Many missing manual pages were completed ([3938](https://github.com/ElementsProject/lightning/pull/3938))
- Build: Fixed compile error on macos ([4019](https://github.com/ElementsProject/lightning/pull/4019))
- pyln: Fixed HTLCs hanging indefinitely if the hook function raises an exception. A safe fallback result is now returned instead. ([4031](https://github.com/ElementsProject/lightning/pull/4031))
- elementsd: PSBTs include correct witness_utxo struct for elements transactions ([4033](https://github.com/ElementsProject/lightning/pull/4033))
- cli: fixed crash with `listconfigs` in `-H` mode ([4012](https://github.com/ElementsProject/lightning/pull/4012))
- Plugins: `bcli` significant speedups for block synchronization ([3985](https://github.com/ElementsProject/lightning/pull/3985))
- Build: On systems with multiple installed versions of the PostgreSQL client library, C-Lightning might link against the wrong version or fail to find the library entirely. `./configure` now uses `pg_config` to locate the library. ([3995](https://github.com/ElementsProject/lightning/pull/3995))
- Build: On some operating systems the postgresql library would not get picked up. `./configure` now uses `pg_config` to locate the headers. ([3991](https://github.com/ElementsProject/lightning/pull/3991))
- libplugin: significant speedups for reading large JSON replies (e.g. calling listsendpays on large nodes, or listchannels / listnodes). ([3957](https://github.com/ElementsProject/lightning/pull/3957))
- plugin: `pay` was rewritten to use the new payment flow. See `legacypay` for old version ([3809](https://github.com/ElementsProject/lightning/pull/3809))
- plugin: `pay` will split payments that are failing due to their size into smaller parts, if recipient supports the `basic_mpp` option ([3809](https://github.com/ElementsProject/lightning/pull/3809))
- plugin: `pay` will split large payments into parts of approximately 10k sat if the recipient supports the `basic_mpp` option ([3809](https://github.com/ElementsProject/lightning/pull/3809))
- plugin: The pay plugin has a new `--disable-mpp` flag that allows opting out of the above two multi-part payment addition. ([3809](https://github.com/ElementsProject/lightning/pull/3809))
- JSON-RPC: new low-level coin selection `fundpsbt` routine. ([3825](https://github.com/ElementsProject/lightning/pull/3825))
- JSON-RPC: The `pay` command now uses the new payment flow, the new `legacypay` command can be used to issue payment with the legacy code if required. ([3826](https://github.com/ElementsProject/lightning/pull/3826))
- JSON-RPC: The `keysend` command allows sending to a node without requiring an invoice first. ([3792](https://github.com/ElementsProject/lightning/pull/3792))
- JSON-RPC: `listfunds` now has a 'scriptpubkey' field. ([3821](https://github.com/ElementsProject/lightning/pull/3821))
- docker: Docker build now includes `LIGHTNINGD_NETWORK` ENV variable which defaults to "bitcoin". An user can override this (e.g. by `-e` option in `docker run`) to run docker container in regtest or testnet or any valid argument to `--network`. ([3813](https://github.com/ElementsProject/lightning/pull/3813))
- cli: We now install `lightning-hsmtool` for your `hsm_secret` needs. ([3802](https://github.com/ElementsProject/lightning/pull/3802))
- JSON-RPC: new call `signpsbt` which will add the wallet's signatures to a provided psbt ([3775](https://github.com/ElementsProject/lightning/pull/3775))
- JSON-RPC: new call `sendpsbt` which will finalize and send a signed PSBT ([3775](https://github.com/ElementsProject/lightning/pull/3775))
- JSON-RPC: Adds two new rpc methods, `reserveinputs` and `unreserveinputs`, which allow for reserving or unreserving wallet UTXOs ([3775](https://github.com/ElementsProject/lightning/pull/3775))
- Python: `pyln.spec.bolt{1,2,4,7}` packages providing python versions of the spec text and defined messages. ([3777](https://github.com/ElementsProject/lightning/pull/3777))
- pyln: new module `pyln.proto.message.bolts` ([3733](https://github.com/ElementsProject/lightning/pull/3733))
- cli: New `--flat` mode for easy grepping of `lightning-cli` output. ([3722](https://github.com/ElementsProject/lightning/pull/3722))
- plugins: new notification type, `coin_movement`, which tracks all fund movements for a node ([3614](https://github.com/ElementsProject/lightning/pull/3614))
- plugin: Added a new `commitment_revocation` hook that provides the plugin with penalty transactions for all revoked transactions, e.g., to push them to a watchtower. ([3659](https://github.com/ElementsProject/lightning/pull/3659))
- JSON-API: `listchannels` now shows channel `features`. ([3685](https://github.com/ElementsProject/lightning/pull/3685))
- plugin: New `invoice_creation` plugin event ([3658](https://github.com/ElementsProject/lightning/pull/3658))
- docs: Install documentation now has information about building for Alpine linux ([3660](https://github.com/ElementsProject/lightning/pull/3660))
- plugin: Plugins can opt out of having an RPC connection automatically initialized on startup. ([3857](https://github.com/ElementsProject/lightning/pull/3857))
- JSON-RPC: `sendonion` has a new optional `bolt11` argument for when it's used to pay an invoice. ([3878](https://github.com/ElementsProject/lightning/pull/3878))
- JSON-RPC: `sendonion` has a new optional `msatoshi` that is used to annotate the payment with the amount received by the destination. ([3878](https://github.com/ElementsProject/lightning/pull/3881))
- JSON-RPC: `fundchannel_cancel` no longer requires its undocumented `channel_id` argument after `fundchannel_complete`. ([3787](https://github.com/ElementsProject/lightning/pull/3787))
- JSON-RPC: `fundchannel_cancel` will now succeed even when executed while a `fundchannel_complete` is ongoing; in that case, it will be considered as cancelling the funding *after* the `fundchannel_complete` succeeds. ([3778](https://github.com/ElementsProject/lightning/pull/3778))
- JSON-RPC: `listfunds` 'outputs' now includes reserved outputs, designated as 'reserved' = true ([3764](https://github.com/ElementsProject/lightning/pull/3764))
- JSON-RPC: `txprepare` now prepares transactions whose `nLockTime` is set to the tip blockheight, instead of using 0. `fundchannel` will use `nLockTime` set to the tip blockheight as well. ([3797](https://github.com/ElementsProject/lightning/pull/3797))
- build: default compile output is prettier and much less verbose ([3686](https://github.com/ElementsProject/lightning/pull/3686))
- config: the `plugin-disable` option now works even if specified before the plugin is found. ([3679](https://github.com/ElementsProject/lightning/pull/3679))
- plugins: The `autoclean` plugin is no longer dynamic (you cannot manage it with the `plugin` RPC command anymore). ([3788](https://github.com/ElementsProject/lightning/pull/3788))
Note: You should always set `allow-deprecated-apis=false` to test for changes.
- JSON-RPC: the `legacypay` method from the pay plugin will be removed after `pay` proves stable ([3809](https://github.com/ElementsProject/lightning/pull/3809))
- protocol: support for optional fields of the reestablish message are now compulsory. ([3782](https://github.com/ElementsProject/lightning/pull/3782))
### Fixed
- JSON-RPC: Reject some bad JSON at parsing. ([3761](https://github.com/ElementsProject/lightning/pull/3761))
- JSON-RPC: The `feerate` parameters now correctly handle the standardness minimum when passed as `perkb`. ([3772](https://github.com/ElementsProject/lightning/pull/3772))
- JSON-RPC: `listtransactions` now displays all txids as little endian ([3741](https://github.com/ElementsProject/lightning/pull/3741))
- JSON-RPC: `pay` now respects maxfeepercent, even for tiny amounts. ([3693](https://github.com/ElementsProject/lightning/pull/3693))
- JSON-RPC: `withdraw` and `txprepare``feerate` can be a JSON number. ([3821](https://github.com/ElementsProject/lightning/pull/3821))
- bitcoin: `lightningd` now always exits if the Bitcoin backend failed unexpectedly. ([3675](https://github.com/ElementsProject/lightning/pull/3675))
- cli: Bash completion on `lightning-cli` now works again ([3719](https://github.com/ElementsProject/lightning/pull/3719))
- config: we now take the `--commit-fee` parameter into account. ([3732](https://github.com/ElementsProject/lightning/pull/3732))
- db: Fixed a failing assertion if we reconnect to a peer that we had a channel with before, and then attempt to insert the peer into the DB twice. ([3801](https://github.com/ElementsProject/lightning/pull/3801))
- hsmtool: Make the password argument optional for `guesstoremote` and `dumpcommitments` sub-commands, as shown in our documentation and help text. ([3822](https://github.com/ElementsProject/lightning/pull/3822))
- macOS: Build for macOS Catalina / Apple clang v11.0.3 fixed ([3756](https://github.com/ElementsProject/lightning/pull/3756))
- protocol: Fixed a deviation from BOLT#2: if both nodes advertised `option_upfront_shutdown_script` feature: MUST include ... a zero-length `shutdown_scriptpubkey`. ([3816](https://github.com/ElementsProject/lightning/pull/3816))
- wumbo: negotiate successfully with Eclair nodes. ([3712](https://github.com/ElementsProject/lightning/pull/3712))
- plugin: `bcli` no longer logs a harmless warning about being unable to connect to the JSON-RPC interface. ([3857](https://github.com/ElementsProject/lightning/pull/3857))
- pay: The `keysend` plugin implements the ability to receive spontaneous payments (keysend) ([3611](https://github.com/ElementsProject/lightning/pull/3611))
- Plugin: the Bitcoin backend plugin API is now final. ([3620](https://github.com/ElementsProject/lightning/pull/3620))
- Plugin: `htlc_accepted` hook can now offer a replacement onion `payload`. ([3611](https://github.com/ElementsProject/lightning/pull/3611))
- Plugin: `feature_set` object added to `init` ([3612](https://github.com/ElementsProject/lightning/pull/3612))
- Plugin: 'flag'-type option now available. ([3586](https://github.com/ElementsProject/lightning/pull/3586))
- JSON API: New `getsharedsecret` command, which lets you compute a shared secret with this node knowing only a public point. This implements the BOLT standard of hashing the ECDH point, and is incompatible with ECIES. ([3490](https://github.com/ElementsProject/lightning/pull/3490))
- JSON API: New optional parameter to the `close` command to control the closing transaction fee negotiation back off step ([3390](https://github.com/ElementsProject/lightning/pull/3390))
- JSON API: `connect` returns `features` of the connected peer on success. ([3612](https://github.com/ElementsProject/lightning/pull/3612))
- JSON API: `listpeers` now has `receivable_msat` ([3572](https://github.com/ElementsProject/lightning/pull/3572))
- JSON API: The fields "opening", "mutual_close", "unilateral_close", "delayed_to_us", "htlc_resolution" and "penalty" have been added to the `feerates` command. ([3570](https://github.com/ElementsProject/lightning/pull/3570))
- JSON API: "htlc_timeout_satoshis" and "htlc_success_satoshis" fields have been added to the `feerates` command. ([3570](https://github.com/ElementsProject/lightning/pull/3570))
- pyln now sends proper error on bad calls to plugin methods ([3640](https://github.com/ElementsProject/lightning/pull/3640))
- devtools: The `onion` tool can now generate, compress and decompress onions for rendez-vous routing ([3557](https://github.com/ElementsProject/lightning/pull/3557))
- doc: An FAQ was added, accessible at https://lightning.readthedocs.io/FAQ.html ([3551](https://github.com/ElementsProject/lightning/pull/3551))
### Changed
- We now use a higher feerate for resolving onchain HTLCs and for penalty transactions ([3592](https://github.com/ElementsProject/lightning/pull/3592))
- We now announce multiple addresses of the same type, if given. ([3609](https://github.com/ElementsProject/lightning/pull/3609))
- pay: Improved the performance of the `pay`-plugin by limiting the `listchannels` when computing the shadow route. ([3617](https://github.com/ElementsProject/lightning/pull/3617))
- JSON API: `invoice``exposeprivatechannels` now includes explicitly named channels even if they seem like dead-ends. ([3633](https://github.com/ElementsProject/lightning/pull/3633))
- Added workaround for lnd rejecting our commitment_signed when we send an update_fee after channel confirmed. ([3634](https://github.com/ElementsProject/lightning/pull/3634))
- We now batch the requests for fee estimation to our Bitcoin backend. ([3570](https://github.com/ElementsProject/lightning/pull/3570))
- We now get more fine-grained fee estimation from our Bitcoin backend. ([3570](https://github.com/ElementsProject/lightning/pull/3570))
- Forwarding messages is now much faster (less inter-daemon traffic) ([3547](https://github.com/ElementsProject/lightning/pull/3547))
- dependencies: We no longer depend on python2 which has reached end-of-life ([3552](https://github.com/ElementsProject/lightning/pull/3552))
### Deprecated
Note: You should always set `allow-deprecated-apis=false` to test for changes.
- JSON API: `fundchannel_start``satoshi` field really deprecated now (use `amount`). ([3603](https://github.com/ElementsProject/lightning/pull/3603))
- JSON API: The "urgent", "slow", and "normal" field of the `feerates` command are now deprecated. ([3570](https://github.com/ElementsProject/lightning/pull/3570))
- JSON API: Removed double wrapping of `rpc_command` payload in `rpc_command` JSON field. ([3560](https://github.com/ElementsProject/lightning/pull/3560))
- Plugins: htlc_accepted_hook "failure_code" only handles simple cases now, use "failure_message". ([3472](https://github.com/ElementsProject/lightning/pull/3472))
- Plugins: invoice_payment_hook "failure_code" only handles simple cases now, use "failure_message". ([3472](https://github.com/ElementsProject/lightning/pull/3472))
### Removed
- JSON API: `listnodes``globalfeatures` output (`features` since in 0.7.3). ([3603](https://github.com/ElementsProject/lightning/pull/3603))
- JSON API: `listpeers``localfeatures` and `globalfeatures` output (`features` since in 0.7.3). ([3603](https://github.com/ElementsProject/lightning/pull/3603))
- JSON API: `peer_connected` hook `localfeatures` and `globalfeatures` output (`features` since in 0.7.3). ([3603](https://github.com/ElementsProject/lightning/pull/3603))
- JSON API: `fundchannel` and `fundchannel_start``satoshi` parameter removed (renamed to `amount` in 0.7.3). ([3603](https://github.com/ElementsProject/lightning/pull/3603))
- JSON API: `close``force` parameter removed (deprecated in 0.7.2.1) ([3603](https://github.com/ElementsProject/lightning/pull/3603))
- JSON API: `sendpay``description` parameter removed (renamed to `label` in 0.7.0). ([3603](https://github.com/ElementsProject/lightning/pull/3603))
### Fixed
- Plugins: A crashing plugin will no longer cause a hook call to be delayed indefinitely ([3539](https://github.com/ElementsProject/lightning/pull/3539))
- Plugins: setting an 'init' feature bit allows us to accept it from peers. ([3609](https://github.com/ElementsProject/lightning/pull/3609))
- Plugins: if an option has a type int or bool, return the option as that type to the plugin's init ([3582](https://github.com/ElementsProject/lightning/pull/3582))
- Plugins: Plugins no longer linger indefinitely if their process terminates ([3539](https://github.com/ElementsProject/lightning/pull/3539))
- JSON API: Pending RPC method calls are now terminated if the handling plugin exits prematurely. ([3639](https://github.com/ElementsProject/lightning/pull/3639))
- JSON API: `fundchannel_start` returns `amount` even when deprecated APIs are enabled. ([3603](https://github.com/ElementsProject/lightning/pull/3603))
- JSON API: Passing 0 as minconf to withdraw allows you to use unconfirmed transaction outputs, even if explicitly passed as the `utxos` parameter ([3593](https://github.com/ElementsProject/lightning/pull/3593))
- JSON API: `txprepare` doesn't crash lightningd anymore if you pass unconfirmed utxos ([3534](https://github.com/ElementsProject/lightning/pull/3534))
- invoice: The invoice parser assumed that an amount without a multiplier was denominated in msatoshi instead of bitcoins. ([3636](https://github.com/ElementsProject/lightning/pull/3636))
- pay: The `pay`-plugin was generating non-contiguous shadow routes ([3617](https://github.com/ElementsProject/lightning/pull/3617))
-`pay` would crash on expired waits with tried routes ([3630](https://github.com/ElementsProject/lightning/pull/3630))
-`pay` would crash when attempting to find cheaper route with exemptfee ([3630](https://github.com/ElementsProject/lightning/pull/3630))
- Multiple definition of chainparams on Fedora (or other really recent gcc) ([3631](https://github.com/ElementsProject/lightning/pull/3631))
- bcli now handles 0msat outputs in gettxout. ([3605](https://github.com/ElementsProject/lightning/pull/3605))
- Fix assertion on reconnect if we fail to run openingd. ([3604](https://github.com/ElementsProject/lightning/pull/3604))
- Use lightning-rfc #740 feespike margin factor of 2 ([3589](https://github.com/ElementsProject/lightning/pull/3589))
- Always broadcast the latest close transaction at the end of the close fee negotiation, instead of sometimes broadcasting the peer's initial closing proposal. ([3556](https://github.com/ElementsProject/lightning/pull/3556))
- Plugin: pluggable backends for Bitcoin data queries, default still bitcoind (using bitcoin-cli). ([3488](https://github.com/ElementsProject/lightning/pull/3488))
- Plugin: Plugins can now signal support for experimental protocol extensions by registering featurebits for `node_announcement`s, the connection handshake, and for invoices. For now this is limited to non-dynamic plugins only ([3477](https://github.com/ElementsProject/lightning/pull/3477))
- Plugin: 'plugin start' now restores initial umask before spawning the plugin process ([3375](https://github.com/ElementsProject/lightning/pull/3375))
- JSON API: `fundchannel` and `fundchannel_start` can now accept an optional parameter, `push_msat`, which will gift that amount of satoshis to the peer at channel open. ([3369](https://github.com/ElementsProject/lightning/pull/3369))
- JSON API: `waitanyinvoice` now supports a `timeout` parameter, which when set will cause the command to fail if unpaid after `timeout` seconds (can be 0). ([3449](https://github.com/ElementsProject/lightning/pull/3449))
- Config: `--rpc-file-mode` sets permissions on the JSON-RPC socket. ([3437](https://github.com/ElementsProject/lightning/pull/3437))
- lightningd: Optimistic locking prevents instances from running concurrently against the same database, providing linear consistency to changes. ([3358](https://github.com/ElementsProject/lightning/pull/3358))
- hsmd: Added fields to hsm_sign_remote_commitment_tx to allow complete validation by signing daemon. ([3363](https://github.com/ElementsProject/lightning/pull/3363))
- Wallet: withdrawal transactions now sets nlocktime to the current tip. ([3465](https://github.com/ElementsProject/lightning/pull/3465))
- elements: Added support for the dynafed block header format and elementsd >=0.18.1 ([3440](https://github.com/ElementsProject/lightning/pull/3440))
### Changed
- JSON API: The hooks `db_write`, `invoice_payment`, and `rpc_command` now accept `{ "result": "continue" }` to mean "do default action". ([3475](https://github.com/ElementsProject/lightning/pull/3475))
- Plugin: Multiple plugins can now register for the htlc_accepted hook. ([3489](https://github.com/ElementsProject/lightning/pull/3489))
- JSON API: `funchannel_cancel`: only the opener of a fundchannel can cancel the channel open ([3336](https://github.com/ElementsProject/lightning/pull/3336))
- JSON API: `sendpay` optional `msatoshi` param for non-MPP (if set), must be the exact amount sent to the final recipient. ([3470](https://github.com/ElementsProject/lightning/pull/3470))
- JSON API: `waitinvoice` now returns error code 903 to designate that the invoice expired during wait, instead of the previous -2 ([3441](https://github.com/ElementsProject/lightning/pull/3441))
- JSON_API: The `connect` command now returns its own error codes instead of a generic -1. ([3397](https://github.com/ElementsProject/lightning/pull/3397))
- Plugin: `notify_sendpay_success` and `notify_sendpay_failure` are now always called, even if there is no command waiting on the result. ([3405](https://github.com/ElementsProject/lightning/pull/3405))
- hsmtool: `hsmtool` now creates its backup copy in the same directory as the original `hsm_secret` file. ([3409](https://github.com/ElementsProject/lightning/pull/3409))
- JSON API: `invoice``exposeprivatechannels` can specify exact channel candidates. ([3351](https://github.com/ElementsProject/lightning/pull/3351))
- JSON API: `db_write` new field `data_version` which contains a numeric transaction counter. ([3358](https://github.com/ElementsProject/lightning/pull/3358))
- JSON API: `plugin stop` result is now accessible using the `result` key instead of the empty ('') key. ([3374](https://github.com/ElementsProject/lightning/pull/3374))
- lightning-cli: specifying `--rpc-file` (without `--network`) has been restored. ([3353](https://github.com/ElementsProject/lightning/pull/3353))
### Deprecated
Note: You should always set `allow-deprecated-apis=false` to test for changes.
- JSON API: The hook `db_write` returning `true`: use `{ "result": "continue" }`. ([3475](https://github.com/ElementsProject/lightning/pull/3475))
- JSON API: The hook `invoice_payment` returning `{}`: use `{ "result": "continue" }`. ([3475](https://github.com/ElementsProject/lightning/pull/3475))
- JSON API: The hook `rpc_command` returning `{"continue": true}`: use `{ "result": "continue" }`. ([3475](https://github.com/ElementsProject/lightning/pull/3475))
- JSON API: `plugin stop` result with an empty ("") key: use "result". ([3374](https://github.com/ElementsProject/lightning/pull/3374))
### Removed
- Plugin: Relative plugin paths are not relative to startup (deprecated v0.7.2.1) ([3471](https://github.com/ElementsProject/lightning/pull/3471))
- JSON API: Dummy fields in listforwards (deprecated v0.7.2.1) ([3471](https://github.com/ElementsProject/lightning/pull/3471))
### Fixed
- Doc: Corrected and expanded `lightning-listpeers.7` documentation. ([3497](https://github.com/ElementsProject/lightning/pull/3497))
- Doc: Fixed factual errors in `lightning-listchannels.7` documentation. ([3494](https://github.com/ElementsProject/lightning/pull/3494))
- Protocol: Corner case where channel could become unusable (https://github.com/lightningnetwork/lightning-rfc/issues/728) ([3500](https://github.com/ElementsProject/lightning/pull/3500))
- Plugins: Dynamic C plugins can now be managed when lightningd is up ([3480](https://github.com/ElementsProject/lightning/pull/3480))
- Doc: `connect`: clarified failure problems and usage. ([3459](https://github.com/ElementsProject/lightning/pull/3459))
- Doc: `fundchannel`: clarify that we automatically `connect`s if your node knows how. ([3459](https://github.com/ElementsProject/lightning/pull/3459))
- Protocol: Now correctly reject "fees" paid when we're the final hop (lightning-rfc#711) ([3474](https://github.com/ElementsProject/lightning/pull/3474))
- JSON API: `txprepare` no longer crashes when more than two outputs are specified ([3384](https://github.com/ElementsProject/lightning/pull/3384))
- Pyln: now includes the "jsonrpc" field to jsonrpc2 requests ([3442](https://github.com/ElementsProject/lightning/pull/3442))
- Plugin: `pay` now detects a previously non-permanent error (`final_cltv_too_soon`) that has been merged into a permanent error (`incorrect_or_unknown_payment_details`), and retries. ([3376](https://github.com/ElementsProject/lightning/pull/3376))
- JSON API: The arguments for `createonion` are now checked to ensure they fit in the onion packet. ([3404](https://github.com/ElementsProject/lightning/pull/3404))
- TOR: We don't send any further request if the return code of connect is not zero or error. ([3408](https://github.com/ElementsProject/lightning/pull/3408))
- Build: Developer mode compilation on FreeBSD. ([3344](https://github.com/ElementsProject/lightning/pull/3344))
- Protocol: We now reject invoices which ask for sub-millisatoshi amounts ([3481](https://github.com/ElementsProject/lightning/pull/3481))
- JSON API: Added `createonion` and `sendonion` JSON-RPC methods allowing the implementation of custom protocol extensions that are not directly implemented in c-lightning itself. ([3260](https://github.com/ElementsProject/lightning/pull/3260))
- JSON API: `listinvoices` now displays the payment preimage if the invoice was paid. ([3295](https://github.com/ElementsProject/lightning/pull/3295))
- JSON API: `listpeers` channels now include `close_to` and `close_to_addr` iff a `close_to` address was specified at channel open ([3223](https://github.com/ElementsProject/lightning/pull/3223))
- The new `pyln-testing` package now contains the testing infrastructure so it can be reused to test against c-lightning in external projects ([3218](https://github.com/ElementsProject/lightning/pull/3218))
- config: configuration files now support `include`. ([3268](https://github.com/ElementsProject/lightning/pull/3268))
- options: Allow the Tor inbound service port differ from 9735 ([3155](https://github.com/ElementsProject/lightning/pull/3155))
- options: Persistent Tor address support ([3155](https://github.com/ElementsProject/lightning/pull/3155))
- plugins: A new plugin hook, `rpc_command` allows a plugin to take over `lightningd` for any RPC command. ([2925](https://github.com/ElementsProject/lightning/pull/2925))
- plugins: Allow the `accepter` to specify an upfront_shutdown_script for a channel via a `close_to` field in the openchannel hook result ([3280](https://github.com/ElementsProject/lightning/pull/3280))
- plugins: Plugins may now handle modern TLV-style payloads via the `htlc_accepted` hook ([3260](https://github.com/ElementsProject/lightning/pull/3260))
- plugins: libplugin now supports writing plugins which register to hooks ([3317](https://github.com/ElementsProject/lightning/pull/3317))
- plugins: libplugin now supports writing plugins which register to notifications ([3317](https://github.com/ElementsProject/lightning/pull/3317))
- protocol: Payment amount fuzzing is restored, but through shadow routing. ([3212](https://github.com/ElementsProject/lightning/pull/3212))
- protocol: We now signal the network we are running on at init. ([3300](https://github.com/ElementsProject/lightning/pull/3300))
- protocol: can now send and receive TLV-style onion messages. ([3335](https://github.com/ElementsProject/lightning/pull/3335))
- protocol: can now send and receive BOLT11 payment_secrets. ([3335](https://github.com/ElementsProject/lightning/pull/3335))
- protocol: can now receive basic multi-part payments. ([3335](https://github.com/ElementsProject/lightning/pull/3335))
- JSON RPC: low-level commands sendpay and waitsendpay can now be used to manually send multi-part payments. ([3335](https://github.com/ElementsProject/lightning/pull/3335))
- tools: A new command, `guesstoremote`, is added to the hsmtool. It is meant to be used to recover funds after an unilateral close of a channel with `option_static_remotekey` enabled. ([3292](https://github.com/ElementsProject/lightning/pull/3292))
:warning: The default network and the default location of the lightning home directory changed. Please make sure that the configuration, key file and database are moved into the network-specific subdirectory.
- config: Default network (new installs) is now bitcoin, not testnet. ([3268](https://github.com/ElementsProject/lightning/pull/3268))
- config: Lightning directory, plugins and files moved into `<network>/` subdir ([3268](https://github.com/ElementsProject/lightning/pull/3268))
- JSON API: The `fundchannel` command now tries to connect to the peer before funding the channel, no need to `connect` before `fundchannel` if an address for the peer is known ([3314](https://github.com/ElementsProject/lightning/pull/3314))
- JSON API: `htlc_accepted` hook has `type` (currently `legacy` or `tlv`) and other fields directly inside `onion`. ([3167](https://github.com/ElementsProject/lightning/pull/3167))
- JSON API: `lightning_` prefixes removed from subdaemon names, including in listpeers `owner` field. ([3241](https://github.com/ElementsProject/lightning/pull/3241))
- JSON API: `listconfigs` now structures plugins and include their options ([3283](https://github.com/ElementsProject/lightning/pull/3283))
- JSON API: the `raw_payload` now includes the first byte, i.e., the realm byte, of the payload as well. This allows correct decoding of a TLV payload in the plugins. ([3261](https://github.com/ElementsProject/lightning/pull/3261))
- logging: formatting made uniform: [NODEID-]SUBSYSTEM: MESSAGE ([3241](https://github.com/ElementsProject/lightning/pull/3241))
- options: `config` and `<network>/config` read by default. ([3268](https://github.com/ElementsProject/lightning/pull/3268))
- options: log-level can now specify different levels for different subsystems. ([3241](https://github.com/ElementsProject/lightning/pull/3241))
- protocol: The TLV payloads for the onion packets are no longer considered an experimental feature and generally available. ([3260](https://github.com/ElementsProject/lightning/pull/3260))
- quirks: We'll now reconnect and retry if we get an error on an established channel. This works around lnd sending error messages that may be non-fatal. ([3340](https://github.com/ElementsProject/lightning/pull/3340))
:warning: If you don't have a config file, you now may need to specify the network to `lightning-cli` ([3268](https://github.com/ElementsProject/lightning/pull/3268))
- JSON API: `htlc_accepted` hook `per_hop_v0` object deprecated, as is `short_channel_id` for the final hop. ([3167](https://github.com/ElementsProject/lightning/pull/3167))
- JSON: `listpays` won't shown payments made via sendpay without a bolt11 string, or before 0.7.0. ([3309](https://github.com/ElementsProject/lightning/pull/3309))
-`pyln-client` now handles unicode characters in JSON-RPC requests and responses correctly. ([3018](https://github.com/ElementsProject/lightning/pull/3018))
- bitcoin: If bitcoind goes backwards (e.g. reindex) refuse to start (unless forced with --rescan). ([3274](https://github.com/ElementsProject/lightning/pull/3274))
- bug: `gossipd` crash on huge number of unknown channels. ([3273](https://github.com/ElementsProject/lightning/pull/3273))
- gossip: No longer discard most `node_announcements` (fixes #3194) ([3262](https://github.com/ElementsProject/lightning/pull/3262))
- options: We disable all dns even on startup the scan for bogus dns servers, if `--always-use-proxy` is set true ([3251](https://github.com/ElementsProject/lightning/pull/3251))
- protocol: "Bad commitment signature" closing channels when we sent back-to-back update_fee messages across multiple reconnects. ([3329](https://github.com/ElementsProject/lightning/pull/3329))
- JSON API: `fundchannel_start` now accepts an optional parameter `close_to`, the address to which these channel funds should be sent to on close. Returns `using_close_to` if will use.
- JSON API: The `plugin` command now returns on error. A timeout of 20 seconds is added to `start` and `startdir` subcommands at the end of which the plugin is errored if it did not complete the handshake with `lightningd`.
- Tor: We default now with autotor to generate if possible temporary ED25519-V3 onions. You can use new option `enable-autotor-v2-mode` to fallback to V2 RSA1024 mode.
- JSON API: a new command `plugin` allows one to manage plugins without restarting `lightningd`.
- Plugin: a new boolean field can be added to a plugin manifest, `dynamic`. It allows a plugin to tell if it can be started or stopped "on-the-fly".
- Plugin: a new boolean field is added to the `init`'s `configuration`, `startup`. It allows a plugin to know if it has been started on `lightningd` startup.
- Plugin: new notifications `invoice_payment`, `forward_event` and `channel_opened`.
- JSON API: `listforwards` removed dummy (zero) fields for `out_msat`, `fee_msat`, `in_channel` and `out_channel` if unknown (i.e. deleted from db, or `status` is `local-failed`.
- wallet: We will now backfill blocks below our wallet start height on demand when we require them to verify gossip messages. This fixes an issue where we would not remove channels on spend that were opened below that start height because we weren't tracking the funding output.
- JSON API: new withdraw methods `txprepare`, `txsend` and `txdiscard`.
- JSON API: add three new RPC commands: `fundchannel_start`, `fundchannel_complete` and `fundchannel_cancel`. Allows a user to initiate and complete a channel open using funds that are in a external wallet.
- Plugin: new hooks `db_write` for intercepting database writes, `invoice_payment` for intercepting invoices before they're paid, `openchannel` for intercepting channel opens, and `htlc_accepted` to decide whether to resolve, reject or continue an incoming or forwarded payment..
- JSON API: `listforwards` now includes the time an HTLC was received and when it was resolved. Both are expressed as UNIX timestamps to facilitate parsing (Issue [#2491](https://github.com/ElementsProject/lightning/issues/2491), PR [#2528](https://github.com/ElementsProject/lightning/pull/2528))
- JSON API: `listforwards` now includes the local_failed forwards with failcode (Issue [#2435](https://github.com/ElementsProject/lightning/issues/2435), PR [#2524](https://github.com/ElementsProject/lightning/pull/2524))
- DB: Store the signatures of channel announcement sent from remote peer into DB, and init channel with signatures from DB directly when reenable the channel.
- JSON API: the command objects that `help` outputs now contain a new string field : `category` (can be "bitcoin", "channels", "network", "payment", "plugins", "utility", "developer" for native commands, or any other new category set by a plugin).
- JSON API: `fundchannel` and `withdraw` now have a new parameter `minconf` that limits coinselection to outputs that have at least `minconf` confirmations (default 1). (#2380)
- JSON API: `listpeers` now includes `funding_allocation_msat`, which returns a map of the amounts initially funded to the channel by each peer, indexed by channel id.