Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsBurr can help you inspect an LLM agent’s earlier execution and start a new branch from a saved point. That is time-travel debugging in a useful sense—but restoring state does not prove that rerunning the branch will reproduce the same model response, tool output, or external effect. To support a claim that “nothing changed,” define exactly what you compare and capture the inputs and outputs that can vary.
What Burr time-travel debugging does—and does not—mean
A Burr application is built from actions and state. Burr’s State documentation describes state as immutable: “It is entirely immutable, meaning that you can only create new states from old ones, not modify them in place.” An action’s state operations therefore produce a new state rather than changing the existing one in place.
As an Amazon Associate I earn from qualifying purchases.
Burr’s tracking system records execution details such as the step name, input, state at execution, timestamp, and result. Its UI is intended to help inspect the state machine and executed steps. The persistence API supports initializing an application from an earlier point, including a fork from an application, partition, and sequence ID.
Together, tracking and persistence let you inspect a run and continue from an earlier state in a new branch. They do not, by themselves, make an external system run backward or guarantee that a recomputed action returns the same result. A model call may produce a different response; a tool may return updated data; a network request may fail; and an action may have already sent an email, charged an account, or written to a database.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
The distinction is central: a restored checkpoint can establish the starting state for a new run. “The recomputed branch is unchanged” is a separate claim that needs a defined comparison and supporting evidence.
How to inspect a run and fork from an earlier point
The exact setup depends on the tracker and persister you configure. In the documented workflow, retain the identifiers that let you find the source execution—such as app_id, an optional partition_key, and a sequence_id. The persistence API’s initialize_from accepts source identifiers to restore or fork from a prior point.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
- Configure tracking or persistence. Choose a tracker or state persister and ensure that it records the execution you need to debug. Burr’s tracking documentation describes
LocalTrackingClient, which writes locally by default under~/.burr; the persistence documentation also describes database and custom persister options. - Locate the relevant execution. Use the tracker or UI to inspect the steps and identify where the behavior diverged. Examine the logged input, state, result, and timestamp for the selected step, along with the run identifiers needed to locate it again.
- Initialize a new application from the saved point. Use
initialize_fromwith the source application and sequence identifiers, and provide the partition identifier if applicable. This gives the new application a branch rooted in the selected earlier state; choose new identifiers for where subsequent state should be stored. - Decide what happens next. Resume at the next action or configure the intended entry point. Be explicit about which inputs come from recorded data and which computations will be performed again. Burr’s RAG example distinguishes forking from continuing an existing application, and shows how a prior state can be used to rewind or fork and then continue.
- Run the diagnostic branch safely. Before executing actions that affect outside systems, decide whether to stub, isolate, or make those effects idempotent. A fork creates a new application branch; it does not undo side effects already performed by the original run.
The official Apache Burr GPT-like multimodal chatbot example captures the practical debugging questions: “Why did this LLM call fail?”, “Things went off the rails, but where?”, and “What if my agent was 20+ steps in … do I have to restart from step 0? or can I go to a specific point in time?” Tracking helps answer where a run went wrong; forking lets you investigate from a prior point without treating the original execution as if it had been erased.
What “the same branch” can mean
There is no single useful meaning of “unchanged” until you choose the boundary. A restored state, a repeated transition path, and identical external effects are different levels of evidence. Decide which one matters before comparing runs.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
- Checkpoint state: Compare a canonical serialization of the state at the fork point. This checks whether the branch started from the state you intended; it does not establish that subsequent actions are identical.
- Transition path: Compare the ordered action or step names and relevant branch decisions. This can show that the same route through the application was taken, even if values within a step differ.
- Action outputs: Compare recorded and recomputed outputs for each action. State equality at the start does not imply output equality after an action has run again.
- Model and tool exchanges: Compare the actual request and response, including the meaningful configuration and inputs. If a model or tool is called again, its new response is a fresh result, not automatically the response from the original run.
- External effects: Check whether writes, messages, payments, or other outside changes occurred. Logs of application state alone may not establish what an external service did.
A useful verification record identifies the source run and fork point, the branch’s configuration, which inputs and outputs were replayed from records versus recomputed, the action path, and the equality rule used. For state comparison, define what serialization includes and how to treat volatile fields such as timestamps or generated identifiers. For side effects, use a test environment, idempotency controls, or stubs where appropriate; do not repeat a non-idempotent operation merely to see whether a branch “matches.” These are engineering practices for substantiating a replay claim, not guarantees made by Burr.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What to keep in mind about persistence and state
Burr’s tracker and persister serve related but distinct purposes: tracking makes execution information inspectable, while persistence supports restoring application state. The documentation describes tracker-based reload as not recommended for production use, so use the current persistence guidance when selecting a production persistence mechanism. The tracking server is described as a way to visualize the state machine and executed steps.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Do not use Burr’s private fields as a shortcut for making a checkpoint. The State API warns that fields prefixed with __ are internal and that modifying them outside the framework is undefined behavior. Create and restore state through the documented APIs instead.
These details reflect the official Apache Burr documentation available on 7 October 2026. Documentation labels and backend recommendations can change, so check the current persistence and tracking guidance before implementing a setup.
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
A practical standard for claiming a replay matched
For a defensible claim, state the level of equivalence rather than saying only “the replay was identical.” For example: “The fork began with the same serialized application state, followed the same action path, and matched the recorded action outputs; model responses were replayed from logs, and external writes were disabled.” That is a bounded claim. If model calls or tools were invoked again, report what was compared and any differences rather than treating the checkpoint as proof of deterministic re-execution.
Burr provides the ingredients to inspect a run and branch from an earlier state. The proof that a recomputed branch did—or did not—change comes from the artifacts you record and the comparison you define.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →
