Change log

All notable changes to the Substreams project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

Substreams builds upon Firehose. Keep track of Firehose releases and Data model updates in the Firehose documentation.


Code generation

  • Added substreams init support for creating a substreams with data from fully-decoded Calls instead of only extracting events.


Code generation

  • Added substreams init support for creating a substreams with the "Dynamic DataSources" pattern (ex: a Factory contract creating pool contracts through the PoolCreated event)

  • Changed substreams init to always add prefixes the tables and entities with the project name

  • Fixed substreams init support for unnamed params and topics on log events


  • Fixed substreams init generated code when dealing with Ethereum ABI events containing array types.

    [!NOTE] For now, the generated code only works with Postgres, an upcoming revision is going to lift that constraint.


  • Fixed store.has_at Wazero signature which was defined as has_at(storeIdx: i32, ord: i32, key_ptr: i32, key_len: i32) but should have been has_at(storeIdx: i32, ord: i64, key_ptr: i32, key_len: i32).

  • Fixed the local substreams alpha service serve ClickHouse deployment which was failing with a message regarding fork handling.

  • Catch more cases of WASM deterministic errors as InvalidArgument.

  • Added some output-stream info to logs.



  • Fixed error-passing between tier2 and tier1 (tier1 will not retry sending requests that fail deterministicly to tier2)

  • Tier1 will now schedule a single job on tier2, quickly ramping up to the requested number of workers after 4 seconds of delay, to catch early exceptions

  • "store became too big" is now considered a deterministic error and returns code "InvalidArgument"



  • Support new networks configuration block in substreams.yaml to override modules' params and initial_block. Network can be specified at run-time, avoiding the need for separate spkg files for each chain.

  • [BREAKING CHANGE] Remove the support for the deriveFrom overrides. The imports, along with the new networks feature, should provide a better mechanism to cover the use cases that deriveFrom tried to address.

[!NOTE] These changes are all handled in the substreams CLI, applying the necessary changes to the package before sending the requests. The Substreams server endpoints do not need to be upgraded to support it.


  • Added networks field at the top level of the manifest definition, with initialBlock and params overrides for each module. See the substreams.yaml.example file in the repository or for more details and example usage.

  • The networks params and `initialBlock`` overrides for the chosen network are applied to the module directly before being sent to the server. All network configurations are kept when packing an .spkg file.

  • Added the --network flag for choosing the network on run, gui and alpha service deploy commands. Default behavior is to use the one defined as network in the manifest.

  • Added the --endpoint flag to substreams alpha service serve to specify substreams endpoint to connect to

  • Added endpoints for Antelope chains

  • Command 'substreams info' now shows the params


  • Removed the handling of the DeriveFrom keyword in manifest, this override feature is going away.

  • Removed the `--skip-package-validation`` option only on run/gui/inspect/info


  • Added the --params flag to alpha service deploy to apply per-module parameters to the substreams before pushing it.

  • Renamed the --parameters flag to --deployment-params in alpha service deploy, to clarify the intent of those parameters (given to the endpoint, not applied to the substreams modules)

  • Small improvement on substreams gui command: no longer reads the .spkg multiple times with different behavior during its process.



  • Fixed bug in substreams init with numbers in ABI types


  • Return the correct GRPC code instead of wrapping it under an "Unknown" error. "Clean shutdown" now returns CodeUnavailable. This is compatible with previous substreams clients like substreams-sql which should retry automatically.

  • Upgraded components to manage the new block encapsulation format in merged-blocks and on the wire required for firehose-core v1.0.0


alpha service deployments

  • Fix fuzzy matching when endpoint require auth headers

  • Fix panic in "serve" when trying to delete a non-existing deployment

  • Add validation check of substreams package before sending deploy request to server



  • Codegen: substreams-database-change to v1.3, properly generates primary key to support chain reorgs in postgres sink.

  • Sink server commands all moved from substreams alpha sink-* to substreams alpha service *

  • Sink server: support for deploying sinks with DBT configuration, so that users can deploy their own DBT models (supported on postgres and clickhouse sinks). Example manifest file segment:

      module: db_out
      type: sf.substreams.sink.sql.v1.Service
        schema: "./schema.sql"
        wire_protocol_access: true
          enabled: true
          enabled: true
          files: "./dbt"
          run_interval_seconds: 60

    where "./dbt" is a folder containing the dbt project.

  • Sink server: added REST interface support for clickhouse sinks. Example manifest file segment:

      module: db_out
      type: sf.substreams.sink.sql.v1.Service
        schema: "./schema.clickhouse.sql"
        wire_protocol_access: true
        engine: clickhouse
          enabled: false
          enabled: false
          enabled: true


  • Fix substreams info cli doc field which wasn't printing any doc output


  • Optimized start of output stream in developer mode when start block is in reversible segment and output module does not have any stores in its dependencies.

  • Fixed bug where the first streamable block of a chain was not processed correctly when the start block was set to the default zero value.



  • Codegen: Now generates separate substreams.{target}.yaml files for sql, clickhouse and graphql sink targets.


  • Codegen: Added support for clickhouse in schema.sql


  • Fixed metrics for time spent in eth_calls within modules stats (server and GUI)

  • Fixed undo json message in 'run' command

  • Fixed stream ending immediately in dev mode when start/end blocks are both 0.

  • Sink-serve: fix missing output details on docker-compose apply errors

  • Codegen: Fixed pluralized entity created for db_out and graph_out



  • Fixed a regression where start block was not resolved correctly when it was in the reversible segment of the chain, causing the substreams to reprocess a segment in tier 2 instead of linearly in tier 1.



  • Missing decrement on metrics substreams_active_requests



  • substreams_active_requests and substreams_counter metrics to substreams-tier1


  • evt_block_time in ms to timestamp in, proto definition and schema.sql



  • This release brings the substreams init command out of alpha! You can quickly generate a Substreams from an Ethereum ABI:

  • See those two new features in action in this tutorial


  • Sink configs can now use protobuf annotations (aka Field Options) to determine how the field will be interpreted in substreams.yaml:

    • load_from_file will put the content of the file directly in the field (string and bytes contents are supported).

    • zip_from_folder will create a zip archive and put its content in the field (field type must be bytes).

    Example protobuf definition:

    import "sf/substreams/v1/options.proto";
    message HostedPostgresDatabase {
      bytes schema = 1 [ (sf.substreams.v1.options).load_from_file = true ];
      bytes extra_config_files = 2 [ (sf.substreams.v1.options).zip_from_folder = true ];

    Example manifest file:

    network: mainnet
      module: main:db_out
      type: sf.substreams.sink.sql.v1.Service
        schema: "./schema.sql"
        wire_protocol_access: true
          enabled: true
          enabled: true
  • substreams info command now properly displays the content of sink configs, optionally writing the fields that were bundled from files to disk with --output-sinkconfig-files-path=</some/path>


  • substreams alpha init renamed to substreams init. It now includes db_out module and schema.sql to support the substreams-sql-sink directly.

  • The override feature has been overhauled. Users may now override an existing substreams by pointing to an override file in run or gui command. This override manifest will have a deriveFrom field which points to the original substreams which is to be overriden. This is useful to port a substreams to one network to another. Example of an override manifest:

    deriveFrom: path/to/mainnet-substreams.spkg #this can also be a remote url
      name: "polygon-substreams"
      version: "100.0.0"
    network: polygon
      module1: 17500000
      module1: "address=2a75ca72679cf1299936d6104d825c9654489058"
  • The substreams run and substreams gui commands now determine the endpoint from the 'network' field in the manifest if no value is passed in the --substreams-endpoint flag.

  • The endpoint for each network can be set by using an environment variable SUBSTREAMS_ENDPOINTS_CONFIG_<network_name>, ex: SUBSTREAMS_ENDPOINTS_CONFIG_MAINNET=my-endpoint:443

  • The substreams alpha init has been moved to substreams init


  • fixed the substreams gui command to correctly compute the stop-block when given a relative value (ex: '-t +10')


Bug fixes

  • Fixed (bumped) substreams protobuf definitions that get embedded in spkg to match the new progress messages from v1.1.12.

  • Regression fix: fixed a bug where negative start blocks would not be resolved correctly when using substreams run or substreams gui.

  • In the request plan, the process previously panicked when errors related to block number validation occurred. Now the error will be returned to the client.


Bug fixes

  • If the initial block or start block is less than the first block in the chain, the substreams will now start from the first block in the chain. Previously, setting the initial block to a block before the first block in the chain would cause the substreams to hang.

  • Fixed a bug where the substreams would fail if the start block was set to a future block. The substreams will now wait for the block to be produced before starting.



  • Complete redesign of the progress messages:

    • Tier2 internal stats are aggregated on Tier1 and sent out every 500ms (no more bursts)

    • No need to collect events on client: a single message now represents the current state

    • Message now includes list of running jobs and information about execution stages

    • Performance metrics has been added to show which modules are executing slowly and where the time is spent (eth calls, store operations, etc.)

Upgrading client and server

[!IMPORTANT] The client and servers will both need to be upgraded at the same time for the new progress messages to be parsed:

  • The new Substreams servers will NOT send the old modules field as part of its progress message, only the new running_jobs, modules_stats, stages.

  • The new Substreams clients will NOT be able to decode the old progress information when connecting to older servers.

However, the actual data (and cursor) will work correctly between versions. Only incompatible progress information will be ignored.



  • Bumped substreams and substreams-ethereum to latest in substreams alpha init.

  • Improved error message when <module_name> is not received, previously this would lead to weird error message, now, if the input is likely a manifest, the error message will be super clear.


  • Fixed compilation errors when tracking some contracts when using substreams alpha init.


  • substreams info now takes an optional second parameter <output-module> to show how the substreams modules can be divided into stages

  • Pack command: added -c flag to allow overriding of certain substreams.yaml values by passing in the path of a yaml file. example yaml contents:

      name: my_custom_package_name
    network: arbitrum-one
      module_name_1: 123123123
      mod1: "custom_parameter"



  • Removed Config.RequestStats, stats are now always enabled.



  • Added metering of live blocks


Backend changes

  • Fixed/Removed: jobs would hang when config parameter StateBundleSize was different from SubrequestsSize. The latter has been removed completely: Subrequests size will now always be aligned with bundle size.

  • Auth: added support for continuous authentication via the grpc auth plugin (allowing cutoff triggered by the auth system).

CLI changes

  • Fixed params handling in gui mode


Backend changes

  • Massive refactoring of the scheduler: prevent excessive splitting of jobs, grouping them into stages when they have the same dependencies. This should reduce the required number of tier2 workers (2x to 3x, depending on the substreams).

  • The tier1 and tier2 config have a new configuration StateStoreDefaultTag, will be appended to the StateStoreURL value to form the final state store URL, ex: StateStoreURL="/data/states" and StateStoreDefaultTag="v2" will make /data/states/v2 the default state store location, while allowing users to provide a X-Sf-Substreams-Cache-Tag header (gated by auth module) to point to /data/states/v1, and so on.

  • Authentication plugin trust can now specify an exclusive list of allowed headers (all lowercase), ex: trust://?allowed=x-sf-user-id,x-sf-api-key-id,x-real-ip,x-sf-substreams-cache-tag

  • The tier2 app no longer has customizable auth plugin (or any Modules), trust will always be used, so that tier can pass down its headers (e.g. X-Sf-Substreams-Cache-Tag). The tier2 instances should not be accessible publicly.

GUI changes

  • Color theme is now adapted to the terminal background (fixes readability on 'light' background)

  • Provided parameters are now shown in the 'Request' tab.

CLI changes


  • alpha init command: replace initialBlock for generated manifest based on contract creation block.

  • alpha init prompt Ethereum chain. Added: Mainnet, BNB, Polygon, Goerli, Mumbai.


  • alpha init reports better progress specially when performing ABI & creation block retrieval.

  • alpha init command without contracts fixed Protogen command invocation.


Backend changes


  • Max-subrequests can now be overridden by auth header X-Sf-Substreams-Parallel-Jobs (note: if your auth plugin is 'trust', make sure that you filter out this header from public access

  • Request Stats logging. When enable it will log metrics associated to a Tier1 and Tier2 request

  • On request, save "substreams.partial.spkg" file to the state cache for debugging purposes.

  • Manifest reader can now read 'partial' spkg files (without protobuf and metadata) with an option.


  • Fixed a bug which caused "live" blocks to be sent while the stream previously received block(s) were historic.

CLI changes


  • In GUI, module output now shows fields with default values, i.e. 0, "", false

v1.1.7 (


Now using plugin: when generating the Protobuf Rust which fixes the warning that remote plugins are deprecated.

Previously we were using remote: But remote plugins when using (which we use to generate the Protobuf) are now deprecated and will cease to function on July 10th, 2023.

The net effect of this is that if you don't update your Substreams CLI to 1.1.7, on July 10th 2023 and after, the substreams protogen will not work anymore.

v1.1.6 (

Backend changes

  • substreams-tier1 and substreams-tier2 are now standalone Apps, to be used as such by server implementations (firehose-ethereum, etc.)

  • substreams-tier1 now listens to Connect protocol, enabling browser-based substreams clients

  • Authentication has been overhauled to take advantage of, allowing the use of a GRPC-based sidecar or reverse-proxy to provide authentication.

  • Metering has been overhauled to take advantage of plugins, allowing the use of a GRPC sidecar or logs to expose usage metrics.

  • The tier2 logs no longer show a parent_trace_id: the trace_id is now the same as tier1 jobs. Unique tier2 jobs can be distinguished by their stage and segment, corresponding to the output_module_name and startblock:stopblock

CLI changes

  • The substreams protogen command now uses this Buf plugin to generate the Rust code for your Substreams definitions.

  • The substreams protogen command no longer generate the FILE_DESCRIPTOR_SET constant which generates an unsued warning in Rust. We don't think nobody relied on having the FILE_DESCRIPTOR_SET constant generated, but if it's the case, you can provide your own buf.gen.yaml that will be used instead of the generated one when doing substreams protogen.

  • Added -H flag on the substreams run command, to set HTTP Headers in the Substreams request.


  • Fixed generated buf.gen.yaml not being deleted when an error occurs while generating the Rust code.


This release fixes data determinism issues. This comes at a 20% performance cost but is necessary for integration with The Graph ecosystem.


  • When upgrading a substreams server to this version, you should delete all existing module caches to benefit from deterministic output


  • Tier1 now records deterministic failures in wasm, "blacklists" identical requests for 10 minutes (by serving them the same InvalidArgument error) with a forced incremental backoff. This prevents accidental bad actors from hogging tier2 resources when their substreams cannot go passed a certain block.

  • Tier1 now sends the ResolvedStartBlock, LinearHandoffBlock and MaxJobWorkers in SessionInit message for the client and gui to show

  • Substreams CLI can now read manifests/spkg directly from an IPFS address (subgraph deployment or the spkg itself), using ipfs://Qm... notation


  • When talking to an updated server, the gui will not overflow on a negative start block, using the newly available resolvedStartBlock instead.

  • When running in development mode with a start-block in the future on a cold cache, you would sometimes get invalid "updates" from the store passed down to your modules that depend on them. It did not impact the caches but caused invalid output.

  • The WASM engine was incorrectly reusing memory, preventing deterministic output. It made things go faster, but at the cost of determinism. Memory is now reset between WASM executions on each block.

  • The GUI no longer panics when an invalid output-module is given as argument


  • Changed default WASM engine from wasmtime to wazero, use SUBSTREAMS_WASM_RUNTIME=wasmtime to revert to prior engine. Note that wasmtime will now run a lot slower than before because resetting the memory in wasmtime is more expensive than in wazero.

  • Execution of modules is now done in parallel within a single instance, based on a tree of module dependencies.

  • The substreams gui and substreams run now accept commas inside a param value. For example: substreams run --param=p1=bar,baz,qux --param=p2=foo,baz. However, you can no longer pass multiple parameters using an ENV variable, or a .yaml config file.


  • Module hashing changed to fix cache reuse on substreams use imported modules

  • Memory leak fixed on rpc-enabled servers

  • GUI more responsive


  • BREAKING: The module hashing algorithm wrongfully changed the hash for imported modules, which made it impossible to leverage caches when composing new substreams off of imported ones.

    • Operationally, if you want to keep your caches, you will need to copy or move the old hashes to the new ones.

      • You can obtain the prior hashes for a given spkg with: substreams info my.spkg, using a prior release of the substreams

      • With a more recent substreams release, you can obtain the new hashes with the same command.

      • You can then cp or mv the caches for each module hash.

    • You can also ignore this change. This will simply invalidate your cache.

  • Fixed a memory leak where "PostJobHooks" were not always called. These are used to hook in rpc calls in Ethereum chain. They are now always called, even if no block has been processed (can be called with nil value for the clock)

  • Jobs that fail deterministically (during WASM execution) on tier2 will fail faster, without retries from tier1.

  • substreams gui command now handles params flag (it was ignored)

  • Substeams GUI responsiveness improved significantly when handling large payloads


  • Added Tracing capabilities, using . See repository for details on how to enable.

Known issues

  • If the cached substreams states are missing a 'full-kv' file in its sequence (not a normal scenario), requests will fail with opening file: not found


This release contains fixes for race conditions that happen when multiple request tries to sync the same range using the same .spkg. Those fixes will avoid weird state error at the cost of duplicating work in some circumstances. A future refactor of the Substreams engine scheduler will come later to fix those inefficiencies.

Operators, please read the operators section for upgrade instructions.


Note This upgrade procedure is applies if your Substreams deployment topology includes both tier1 and tier2 processes. If you have defined somewhere the config value substreams-tier2: true, then this applies to you, otherwise, if you can ignore the upgrade procedure.

This release includes a small change in the internal RPC layer between tier1 processes and tier2 processes. This change requires an ordered upgrade of the processes to avoid errors.

The components should be deployed in this order:

  1. Deploy and roll out tier1 processes first

  2. Deploy and roll out tier2 processes in second

If you upgrade in the wrong order or if somehow tier2 processes start using the new protocol without tier1 being aware, user will end up with backend error(s) saying that some partial file are not found. Those will be resolved only when tier1 processes have been upgraded successfully.


  • Fixed a race when multiple Substreams request execute on the same .spkg, it was causing races between the two executors.

  • GUI: fixed an issue which would slow down message consumption when progress page was shown in ascii art "bars" mode

  • GUI: fixed the display of blocks per second to represent actual blocks, not messages count


  • [binary]: Commands substreams <...> that fails now correctly return an exit code 1.

  • [library]: The manifest.NewReader signature changed and will now return a *Reader, error (previously *Reader).


  • [library]: The manifest.Reader gained the ability to infer the path if provided with input "" based on the current working directory.

  • [library]: The manifest.Reader gained the ability to infer the path if provided with input that is a directory.


This release contains bug fixes and speed/scaling improvements around the Substreams engine. It also contains few small enhancements for substreams gui.

This release contains an important bug that could have generated corrupted store state files. This is important for developers and operators.

Sinkers & Developers

The store state files will be fully deleted on the Substreams server to start fresh again. The impact for you as a developer is that Substreams that were fully synced will now need to re-generate from initial block the store's state. So you might see long delays before getting a new block data while the Substreams engine is re-computing the store states from scratch.


You need to clear the state store and remove all the files that are stored under substreams-state-store-url flag. You can also make it point to a brand new folder and delete the old one after the rollout.


  • Fix a bug where not all extra modules would be sent back on debug mode

  • Fixed a bug in tier1 that could result in corrupted state files when getting close to chain HEAD

  • Fixed some performance and stalling issues when using GCS for blocks

  • Fixed storage logs not being shown properly

  • GUI: Fixed panic race condition

  • GUI: Cosmetic changes


  • GUI: Added traceID


This release introduces a new RPC protocol and the old one has been removed. The new RPC protocol is in a new Protobuf package sf.substreams.rpc.v2 and it drastically changes how chain re-orgs are signaled to the user. Here the highlights of this release:

  • Getting rid of undo payload during re-org

  • substreams gui Improvements

  • Substreams integration testing

  • Substreams Protobuf definitions updated

Getting rid of undo payload during re-org

Previously, the GRPC endpoint sf.substreams.v1.Stream/Blocks would send a payload with the corresponding "step", NEW or UNDO.

Unfortunately, this led to some cases where the payload could not be deterministically generated for old blocks that had been forked out, resulting in a stalling request, a failure, or in some worst cases, incomplete data.

The new design, under sf.substreams.rpc.v2.Stream/Blocks, takes care of these situations by removing the 'step' component and using these two messages types:

  • sf.substreams.rpc.v2.BlockScopedData when chain progresses, with the payload

  • sf.substreams.rpc.v2.BlockUndoSignal during a reorg, with the last valid block number + block hash

The client now has the burden of keeping the necessary means of performing the undo actions (ex: a map of previous values for each block). The BlockScopedData message now includes the final_block_height to let you know when this "undo data" can be discarded.

With these changes, a substreams server can even handle a cursor for a block that it has never seen, provided that it is a valid cursor, by signaling the client to revert up to the last known final block, trading efficiency for resilience in these extreme cases.

substreams gui Improvements

  • Added key 'f' shortcut for changing display encoding of bytes value (hex, pruned string, base64)

  • Added jq search mode (hit / twice). Filters the output with the jq expression, and applies the search to match all blocks.

  • Added search history (with up/down), similar to less.

  • Running a search now applies it to all blocks, and highlights the matching ones in the blocks bar (in red).

  • Added O and P, to jump to prev/next block with matching search results.

  • Added module search with m, to quickly switch from module to module.

Substreams integration testing

Added a basic Substreams testing framework that validates module outputs against expected values. The testing framework currently runs on substreams run command, where you can specify the following flags:

  • test-file Points to a file that contains your test specs

  • test-verbose Enables verbose mode while testing.

The test file, specifies the expected output for a given substreams module at a given block.

Substreams Protobuf definitions updated

We changed the Substreams Protobuf definitions making a major overhaul of the RPC communication. This is a breaking change for those consuming Substreams through gRPC.

Note The is no breaking changes for Substreams developers regarding your Rust code, Substreams manifest and Substreams package.

  • Removed the Request and Response messages (and related) from sf.substreams.v1, they have been moved to sf.substreams.rpc.v2. You will need to update your usage if you were consuming Substreams through gRPC.

  • The new Request excludes fields and usages that were already deprecated, like using multiple module_outputs.

  • The Response now contains a single module output

  • In development mode, the additional modules output can be inspected under debug_map_outputs and debug_store_outputs.

Separating Tier1 vs Tier2 gRPC protocol (for Substreams server operators)

Now that the Blocks request has been moved from sf.substreams.v1 to sf.substreams.rpc.v2, the communication between a substreams instance acting as tier1 and a tier2 instance that performs the background processing has also been reworked, and put under sf.substreams.internal.v2.Stream/ProcessRange. It has also been stripped of parameters that were not used for that level of communication (ex: cursor, logs...)


  • The final_blocks_only: true on the Request was not honored on the server. It now correctly sends only blocks that are final/irreversible (according to Firehose rules).

  • Prevent substreams panic when requested module has unknown value for "type"


  • The substreams run command now has flag --final-blocks-only

This should be the last release before a breaking change in the API and handling of the reorgs and UNDO messages.


  • Added support for resolving a negative start-block on server

  • CHANGED: The run command now resolves a start-block=-1 from the head of the chain (as supported by the servers now). Prior to this change, the -1 value meant the 'initialBlock' of the requested module. The empty string is now used for this purpose,

  • GUI: Added support for search, similar to less, with /.

  • GUI: Search and output offset is conserved when switching module/block number in the "Output" tab.

  • Library: protobuf message descriptors now exposed in the manifest/ package. This is something useful to any sink that would need to interpret the protobuf messages inside a Package.

  • Added support for resolving a negative start-block on server (also added to run command)

  • The run and gui command no longer resolve a start-block=-1 to the 'initialBlock' of the requested module. To get this behavior, simply assign an empty string value to the flag start-block instead.

  • Added support for search within the Substreams gui output view. Usage of search within output behaves similar to the less command, and can be toggled with "/".

  • Release was retracted because it contained the refactoring expected for 1.1.0 by mistake, check instead.


  • Fixed "undo" messages incorrectly contained too many module outputs (all modules, with some duplicates).

  • Fixed status bar message cutoff bug

  • Fixed substreams run when manifest contains unknown attributes

  • Fixed bubble tea program error when existing the run command


  • Added command substreams gui, providing a terminal-based GUI to inspect the streamed data. Also adds --replay support, to save a stream to replay.log and load it back in the UI later. You can use it as you would substreams run. Feedback welcome.

  • Modified command substreams protogen, defaulting to generating the file alongside the rust bindings. Also added --generate-mod-rs flag to toggle generation.

  • Added support for module parameterization. Defined in the manifest as:

  name: my_module
    params: string

  my_module: "0x123123"
  "imported:module": override value from imported module

and on the command-line as:

  • substreams run -p module=value -p "module2=other value" ...

Servers need to be updated for packages to be able to be consumed this way.

This change keeps backwards compatibility. Old Substreams Packages will still work the same, with no changes to module hashes.


  • Added support for {version} template in --output-file flag value on substreams pack.

  • Added fuel limit to wasm execution as a server-side option, preventing wasm process from running forever.

  • Added 'Network' and 'Sink{Type, Module, Config}' fields in the manifest and protobuf definition for future bundling of substreams sink definitions within a substreams package.


  • Improved execution speed and module loading speed by bumping to WASM Time to version 4.0.

  • Improved developer experience on the CLI by making the <manifest> argument optional.

    The CLI when <manifest> argument is not provided will now look in the current directory for a substreams.yaml file and is going to use it if present. So if you are in your Substreams project and your file is named substreams.yaml, you can simply do substreams pack, substreams protogen, etc.

    Moreover, we added to possibility to pass a directory containing a substreams.yaml directly so substreams pack path/to/project would work as long as path/to/project contains a file named substreams.yaml.

  • Fixed a bug that was preventing production mode to complete properly when using a bounded block range.

  • Improved overall stability of the Substreams engine.

Operators Notes

  • Breaking Config values substreams-stores-save-interval and substreams-output-cache-save-interval have been merged together into substreams-cache-save-interval in the firehose-<chain> repositories. Refer to chain specific firehose-<chain> repository for further details.


  • The <manifest> can point to a directory that contains a substreams.yaml file instead of having to point to the file directly.

  • The <manifest> parameter is now optional in all commands requiring it.


  • Fixed valuetype mismatch for stores

  • Fixed production mode not completing when block range was specified

  • Fixed tier1 crashing due to missing context canceled check.

  • Fixed some code paths where locking could have happened due to incorrect checking of context cancellation.

  • Request validation for blockchain's input type is now made only against the requested module it's transitive dependencies.


  • Updated WASM Time library to 4.0.0 leading to improved execution speed.


  • Remove distinction between output-save-interval and store-save-interval.

  • substreams init has been moved under substreams alpha init as this is a feature included by mistake in latest release that should not have been displayed in the main list of commands.

  • substreams codegen has been moved under substreams alpha codegen as this is a feature included by mistake in latest release that should not have been displayed in the main list of commands.

This upcoming release is going to bring significant changes on how Substreams are developed, consumed and speed of execution. Note that there is no breaking changes related to your Substreams' Rust code, only breaking changes will be about how Substreams are run and available features/flags.

Here the highlights of elements that will change in next release:

In this rest of this post, we are going to go through each of them in greater details and the implications they have for you. Full changelog is available after.

Warning Operators, refer to Operators Notes section for specific instructions of deploying this new version.

Production vs development mode

We introduce an execution mode when running Substreams, either production mode or development mode. The execution mode impacts how the Substreams get executed, specifically:

  • The time to first byte

  • The module logs and outputs sent back to the client

  • How parallel execution is applied through the requested range

The difference between the modes are:

  • In development mode, the client will receive all the logs of the executed modules. In production mode, logs are not available at all.

  • In development mode, module's are always re-executed from request's start block meaning now that logs will always be visible to the user. In production mode, if a module's output is found in cache, module execution is skipped completely and data is returned directly.

  • In development mode, only backward parallel execution can be effective. In production mode, both backward parallel execution and forward parallel execution can be effective. See Enhanced parallel execution section for further details about parallel execution.

  • In development mode, every module's output is returned back in the response but only root module is displayed by default in substreams CLI (configurable via a flag). In production mode, only root module's output is returned.

  • In development mode, you may request specific store snapshot that are in the execution tree via the substreams CLI --debug-modules-initial-snapshots flag. In production mode, this feature is not available.

The execution mode is specified at that gRPC request level and is the default mode is development. The substreams CLI tool being a development tool foremost, we do not expect people to activate production mode (-p) when using it outside for maybe testing purposes.

If today's you have sink code making the gRPC request yourself and are using that for production consumption, ensure that field production_mode in your Substreams request is set to true. StreamingFast provided sink like substreams-sink-postgres, substreams-sink-files and others have already been updated to use production_mode by default.

Final note, we recommend to run the production mode against a compiled .spkg file that should ideally be released and versioned. This is to ensure stable modules' hashes and leverage cached output properly.

Single module output

We now only support 1 output module when running a Substreams, while prior this release, it was possible to have multiple ones.

  • Only a single module can now be requested, previous version allowed to request N modules.

  • Only map module can now be requested, previous version allowed map and store to be requested.

  • InitialSnapshots is now forbidden in production mode and still allowed in development mode.

  • In development mode, the server sends back output for all executed modules (by default the CLI displays only requested module's output).

Note We added output_module to the Substreams request and kept output_modules to remain backwards compatible for a while. If an output_module is specified we will honor that module. If not we will check output_modules to ensure there is only 1 output module. In a future release, we are going to remove output_modules altogether.

With the introduction of development vs production mode, we added a change in behavior to reduce frictions this changes has on debugging. Indeed, in development mode, all executed modules's output will be sent be to the user. This includes the requested output module as well as all its dependencies. The substreams CLI has been adjusted to show only the output of the requested output module by default. The new substreams CLI flag -debug-modules-output can be used to control which modules' output is actually displayed by the CLI.

Migration Path If you are currently requesting more than one module, refactor your Substreams code so that a single map module aggregates all the required information from your different dependencies in one output.

Output module must be of type map

It is now forbidden to request a store module as the output module of the Substreams request, the requested output module must now be of kind map. Different factors have motivated this change:

  • Recently we have seen incorrect usage of store module. A store module was not intended to be used as a persistent long term storage, store modules were conceived as a place to aggregate data for later steps in computation. Using it as a persistent storage make the store unmanageable.

  • We had always expected users to consume a map module which would return data formatted according to a final sink spec which will then permanently store the extracted data. We never envisioned store to act as long term storage.

  • Forward parallel execution does not support a store as its last step.

Migration Path If you are currently using a store module as your output store. You will need to create a map module that will have as input the deltas of said store module, and return the deltas.


Let's assume a Substreams with these dependencies: [block] --> [map_pools] --> [store_pools] --> [map_transfers]

  • Running substreams run substreams.yaml map_transfers will only print the outputs and logs from the map_transfers module.

  • Running substreams run substreams.yaml map_transfers --debug-modules-output=map_pools,map_transfers,store_pools will print the outputs of those 3 modules.

InitialSnapshots is now a development mode feature only

Now that a store cannot be requested as the output module, the InitialSnapshots did not make sense anymore to be available. Moreover, we have seen people using it to retrieve the initial state and then continue syncing. While it's a fair use case, we always wanted people to perform the synchronization using the streaming primitive and not by using store as long term storage.

However, the InitialSnapshots is a useful tool for debugging what a store contains at a given block. So we decided to keep it in development mode only where you can request the snapshot of a store module when doing your request. In the Substreams' request/response, initial_store_snapshot_for_modules has been renamed to debug_initial_store_snapshot_for_modules, snapshot_data to debug_snapshot_data and snapshot_complete to debug_snapshot_complete.

Migration Path If you were relying on InitialSnapshots feature in production. You will need to create a map module that will have as input the deltas of said store module, and then synchronize the full state on the consuming side.


Let's assume a Substreams with these dependencies: [block] --> [map_pools] --> [store_pools] --> [map_transfers]

  • Running substreams run substreams.yaml map_transfers -s 1000 -t +5 --debug-modules-initial-snapshot=store_pools will print all the entries in store_pools at block 999, then continue with outputs and logs from map_transfers in blocks 1000 to 1004.

Enhanced parallel execution

There are 2 ways parallel execution can happen either backward or forward.

Backward parallel execution consists of executing in parallel block ranges from the module's start block up to the start block of the request. If the start block of the request matches module's start block, there is no backward parallel execution to perform. Also, this is happening only for dependencies of type store which means that if you depends only on other map modules, no backward parallel execution happens.

Forward parallel execution consists of executing in parallel block ranges from the start block of the request up to last known final block (a.k.a the irreversible block) or the stop block of the request, depending on which is smaller. Forward parallel execution significantly improves the performance of the Substreams as we execute your module in advanced through the chain history in parallel. What we stream you back is the cached output of your module's execution which means essentially that we stream back to you data written in flat files. This gives a major performance boost because in almost all cases, the data will be already for you to consume.

Forward parallel execution happens only in production mode is always disabled when in development mode. Moreover, since we read back data from cache, it means that logs of your modules will never be accessible as we do not store them.

Backward parallel execution still occurs in development and production mode. The diagram below gives details about when parallel execution happen.

You can see that in production mode, parallel execution happens before the Substreams request range as well as within the requested range. While in development mode, we can see that parallel execution happens only before the Substreams request range, so between module's start block and start block of requested range (backward parallel execution only).

Operators Notes

The state output format for map and store modules has changed internally to be more compact in Protobuf format. When deploying this new version, previous existing state files should be deleted or deployment updated to point to a new store location. The state output store is defined by the flag --substreams-state-store-url flag parameter on chain specific binary (i.e. fireeth).


  • Added production_mode to Substreams Request

  • Added output_module to Substreams Request


  • Fixed Ctrl-C not working directly when in TUI mode.

  • Added Trace ID printing once available.

  • Added command substreams tools analytics store-stats to get statistic for a given store.

  • Added --debug-modules-output (comma-separated module names) (unavailable in production mode).

  • Breaking Renamed flag --initial-snapshots to --debug-modules-initial-snapshots (comma-separated module names) (unavailable in production mode).

  • Moved Rust modules to


  • Gained significant execution time improvement when saving and loading stores, during the squashing process by leveraging vtprotobuf

  • Added XDS support for tier 2s

  • Added intrinsic support for type bigdecimal, will deprecate bigfloat

  • Significant improvements in code-coverage and full integration tests.


  • Added substreams tools proxy <package> subcommand to allow calling substreams with a pre-defined package easily from a web browser using bufbuild/connect-web

  • Lowered GRPC client keep alive frequency, to prevent "Too Many Pings" disconnection issue.

  • Added a fast failure when attempting to connect to an unreachable substreams endpoint.

  • CLI is now able to read .spkg from gs://, s3:// and az:// URLs, the URL format must be supported by our dstore library).

  • Command substreams pack is now restricted to local manifest file.

  • Added command substreams tools module to introspect a store state in storage.

  • Made changes to allow for substreams CLI to run on Windows OS (thanks @robinbernon).

  • Added flag --output-file <template> to substreams pack command to control where the .skpg is written, {manifestDir} and {spkgDefaultName} can be used in the template value where {manifestDir} resolves to manifest's directory and {spkgDefaultName} is the pre-computed default name in the form <name>-<version> where <name> is the manifest's "" value (_ values in the name are replaced by -) and <version> is package.version value.

  • Fixed relative path not resolved correctly against manifest's location in protobuf.files list.

  • Fixed relative path not resolved correctly against manifest's location in binaries list.

  • substreams protogen <package> --output-path <path> flag is now relative to <package> if <package> is a local manifest file ending with .yaml.

  • Endpoint's port is now validated otherwise when unspecified, it creates an infinite 'Connecting...' message that will never resolves.


  • Fixed error when importing http/https .spkg files in imports section.

New updatePolicy append, allows one to build a store that concatenates values and supports parallelism. This affects the server, the manifest format (additive only), the substreams crate and the generated code therein.

Rust API

  • Store APIs methods now accept key of type AsRef<str> which means for example that both String an &str are accepted as inputs in:

    • StoreSet::set

    • StoreSet::set_many

    • StoreSet::set_if_not_exists

    • StoreSet::set_if_not_exists_many

    • StoreAddInt64::add

    • StoreAddInt64::add_many

    • StoreAddFloat64::add

    • StoreAddFloat64::add_many

    • StoreAddBigFloat::add

    • StoreAddBigFloat::add_many

    • StoreAddBigInt::add

    • StoreAddBigInt::add_many

    • StoreMaxInt64::max

    • StoreMaxFloat64::max

    • StoreMaxBigInt::max

    • StoreMaxBigFloat::max

    • StoreMinInt64::min

    • StoreMinFloat64::min

    • StoreMinBigInt::min

    • StoreMinBigFloat::min

    • StoreAppend::append

    • StoreAppend::append_bytes

    • StoreGet::get_at

    • StoreGet::get_last

    • StoreGet::get_first

  • Low-level state methods now accept key of type AsRef<str> which means for example that both String an &str are accepted as inputs in:

    • state::get_at

    • state::get_last

    • state::get_first

    • state::set

    • state::set_if_not_exists

    • state::append

    • state::delete_prefix

    • state::add_bigint

    • state::add_int64

    • state::add_float64

    • state::add_bigfloat

    • state::set_min_int64

    • state::set_min_bigint

    • state::set_min_float64

    • state::set_min_bigfloat

    • state::set_max_int64

    • state::set_max_bigint

    • state::set_max_float64

    • state::set_max_bigfloat

  • Bumped prost (and related dependencies) to ^0.11.0


  • Environment variables are now accepted in manifest's imports list.

  • Environment variables are now accepted in manifest's protobuf.importPaths list.

  • Fixed relative path not resolved correctly against manifest's location in imports list.

  • Changed the output modes: module-* modes are gone and become the format for jsonl and json. This means all printed outputs are wrapped to provide the module name, and other metadata.

  • Added --initial-snapshots (or -i) to the run command, which will dump the stores specified as output modules.

  • Added color for ui output mode under a tty.

  • Added some request validation on both client and server (validate that output modules are present in the modules graph)


  • Added support to serve the initial snapshot


  • Changed substreams manifest info -> substreams info

  • Changed substreams manifest graph -> substreams graph

  • Updated usage


  • Multiple fixes to boundaries

substreams server

  • Various bug fixes around store and parallel execution.

substreams CLI

  • Fix null pointer exception at the end of CLI run in some cases.

  • Do log last error when the CLI exit with an error has the error is already printed to the user and it creates a weird behavior.

substreams Docker

  • Ensure arguments can be passed to Docker built image.

substreams server

  • Various bug fixes around store and parallel execution.

  • Fixed logs being repeated on module with inputs that was receiving nothing.

substreams crate

  • Added substreams::hex wrapper around hex_literal::hex macro

substreams CLI

  • Added substreams run -o ui|json|jsonl|module-json|module-jsonl.


  • Fixed a whole bunch of issues, in parallel processing. More stable caching. See chain-specific releases.

  • Fixed substreams crate usage from tagged version published on

  • Changed startBlock to initialBlock in substreams.yaml manifests.

  • code: is now defined in the binaries section of the manifest, instead of in each module. A module can select which binary with the binary: field on the Module definition.

  • Added substreams inspect ./substreams.yaml or inspect some.spkg to see what's inside. Requires protoc to be installed (which you should have anyway).

  • Added command substreams protogen that writes a temporary buf.gen.yaml and generates Rust structs based on the contents of the provided manifest or package.

  • Added substreams::handlers macros to reduce boilerplate when create substream modules.

    substreams::handlers::map is used for the handlers corresponding to modules of type map. Modules of type map should return a Result where the error is of type Error

    /// Map module example
    pub fn map_module_func(blk: eth::Block) -> Result<erc721::Transfers, Error> {

    substreams::handlers::store is used for the handlers corresponding to modules of type store. Modules of type store should have no return value.

    /// Map module example
    pub fn store_module(transfers: erc721::Transfers, s: store::StoreAddInt64, pairs: store::StoreGet, tokens: store::StoreGet) {

  • Implemented packages (see docs).

  • Added substreams::Hex wrapper type to more easily deal with printing and encoding bytes to hexadecimal string.

  • Added substreams::log::info!(...) and substreams::log::debug!(...) supporting formatting arguments (acts like println!() macro).

  • Added new field logs_truncated that can be used to determined if logs were truncated.

  • Augmented logs truncation limit to 128 KiB per module per block.

  • Updated substreams run to properly report module progress error.

  • When a module WASM execution error out, progress with failure logs is now returned before closing the substreams connection.

  • The API token is not passed anymore if the connection is using plain text option --plaintext.

  • The -c (or --compact-output) can be used to print JSON as a single compact line.

  • The --stop-block flag on substream run can be defined as +1000 to stream from start block + 1000.

  • Added Dockerfile support.


  • Improved defaults for --proto-path and --proto, using globs.

  • WASM file paths in substreams.yaml manifests now resolve relative to the location of the yaml file.

  • Added substreams manifest package to create .pb packages to simplify querying using other languages. See the python example.

  • Added substreams manifest graph to show the Mermaid graph alone.

  • Improved mermaid graph layout.

  • Removed native Go code support for now.


  • Always writes store snapshots, each 10,000 blocks.

  • A few tools to manage partial snapshots under substreams tools


See for usage docs..

  • Removed local command. See for instructions on how to run locally now. Build sfeth from source for now.

  • Changed the remote command to run.

  • Changed run command's --substreams-api-key-envvar flag to --substreams-api-token-envvar, and its default value is changed from SUBSTREAMS_API_KEY to SUBSTREAMS_API_TOKEN. See to learn how to obtain such tokens.

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