Whole-brain spiking models that run the connectome as a network.
Eon Systems PBC
Eon Systems' open re-implementation of the Shiu et al. (Nature 2024) leaky integrate-and-fire whole-brain model, covering roughly 138,000 FlyWire v783 neurons and 5 million synapses and runnable on Brian2 (CPU/CUDA), PyTorch, NEST GPU and GeNN backends so users can stimulate or silence any population and watch activity propagate. In a March 10, 2026 update the company reported coupling this brain to a NeuroMechFly v2 body in MuJoCo, describing grooming, feeding and foraging behaviours emerging from the closed sensorimotor loop, which it calls the first embodied fly upload.
annel0
A fast GPU simulator for connectome-constrained spiking models of the Drosophila central nervous system, published together with a record of what it could not establish. It started from the question the viral wave skipped, that everyone reads the brain but nobody changes it, and ends by setting out in measured terms why that question cannot yet be answered honestly. MaleCNS v1.0 is imported to a CSR graph and FlyWire 783 exactly, so someone else's published predictions can be replicated; that replication lands at a median ratio of 1.01 and a correlation of 0.970 across thirteen neurons.
suanmiao
Runs the measured MaleCNS wiring, 165,122 neurons and 25,563,197 synapses, as a recurrent network and trains it to steer a car from a 64 by 32 pixel windscreen. The adjacency never changes; what is learned is one gain per synapse and one leak per neuron. On held-out streets with parked cars, oncoming traffic and a slow car to overtake it completes 58 of 60 runs across three independent sets with no collisions against any car. The site replays logged state rather than re-simulating, puts the real input beside the drive, and publishes the failures too.
nicodunks
A paired experiment on the MaleCNS wiring graph (166,606 classified neurons, roughly 25.6 million connections) asking whether blocking the output of the inhibitory mAL pathway lets male-associated sensory input reach courtship-related P1 neurons. Both arms get identical inputs and the same firing rules; the only change is the mAL block. All 36 combinations of three input pathways, three seeds and two inhibition settings were run, and the README states plainly that the cell identities and connection effects stay modelling assumptions rather than measured properties.
Erfara Labs (@erfaralabs)
Injects a Drosophila connectome graph of 28,994 neurons and 1,814,208 directed synaptic edges into layer 16 of SmolLM2-360M as a persistent leaky-integrator reservoir, without retraining the graph. In-degree normalisation holds the unweighted graph near criticality (largest Lyapunov exponent +0.0309, branching ratio 1.0220). The claim is tested against a degree-preserving null: scrambling the biological targets costs 0.0781 nats of cross-entropy, about 1.58 per cent. The README calls the graph hemibrain plus ventral nerve cord but never names the released dataset behind it.
Roxx0x
Uses the larval fruit fly connectome of Winding et al. 2023, 2,952 neurons and about 110,000 connections, as a fixed reservoir. The wiring is never modified, because you cannot edit an animal's connectome; only a one-layer linear readout is trained on the activity it produces. On handwritten digits that readout reaches 94 per cent against a 10 per cent baseline. It installs with pip, downloads the connectome once and exposes digit and time-series tasks behind a small API.
ZeroXClem
Closes the sensorimotor loop in the browser: rendered images drive a compound eye sampled at the connectome's 1,771 column directions, the optic-lobe rate model feeds the whole MaleCNS graph, descending-neuron rates drive the wings, and the body's new pose renders the next frame. It is an explicit combination of two upstream projects joined at MaleCNS body IDs, AbijahKaj's optic-lobe front end and Xenova's whole-CNS WebGPU back end, and it ships an ablation bench that produced the published cruise figures.
eonfathom (Michael)
A GPU simulator aiming at real-time or faster execution of the whole FlyWire brain, 139,255 neurons and 54.5 million synapses, on a single consumer NVIDIA card. The engineering is the point: leaky integrate-and-fire neurons, CSR sparse connectivity with FP16 weights, a push model that only processes synapses of neurons that actually fired, warp-ballot spike detection with bit-packed flags, and warp-per-spike load balancing. Connectivity comes from Shiu et al.'s v783 release and annotations from flywire_annotations.
Artem X (@artem-x-meta)
Combines a NeuroMechFly body in MuJoCo with MaleCNS connectome data and explicit behavioural controllers. The hybrid mode covers walking, odour-guided food search, contact feeding through an articulated proboscis, grooming, sleep pressure and waking; a separate two-fly arena adds shared food, body collisions, pushing, foreleg fencing and retreat. The README states that the demo clips were recorded with the connectome disabled, showing the engineered controllers, and that this is an experimental model rather than a validated digital fly.
Mehran (@mehrantsi)
A native Rust and Metal implementation of the published FlyWire leaky integrate-and-fire model, with Python kept as an independent Brian2/NumPy verification lane and as the offline Parquet-to-CSR compiler. It now carries a Rust embodiment layer too: MuJoCo runs an exported NeuroMechFly body behind a fixed-rate sensory bridge and a native viewer. A separate experimental integration connects MaleCNS v1.0, 166,700 neurons and 24,469,412 signed edges including the nerve cord, adding no cross-specimen wiring. A paired control run disconnects the motor readout while the neurons keep running.
tel∅s (@tel-0s)
Gives the MaleCNS v1.0 connectome colour vision, smell, taste and wind sense, a body that walks, jumps and flies, and a room with a table and fruit on it. The console shows a body camera, an orbit view, both retinal mosaics, antennal inputs and simultaneous population, motor and body readouts, with switches for simulated central-complex steering, anemotaxis and escape gating. The connectome is never trained or edited; everything else rests on a documented set of physiological assumptions.
Lulzx
An embodied whole-CNS simulation that runs in a desktop browser: a 165,122-neuron MaleCNS v1.0 brain in a MuJoCo flybody body with a flyvis-trained compound-eye front end. Four views ship together, a connectome viewer with stimulable cell types, an algorithmic-structures page (ring attractor, expansion coding, motif census), an arena where you place sugar, odour and threats and watch a fly's brain in an inset, and an anatomy viewer. An endogenous-activity module supplies the spontaneous drive the connectome model lacks, entering only as synaptic input to identified descending neurons.
Ahmet Barış Günaydın (@abgnydn)
Fire a real descending neuron in the FlyWire connectome and watch the spike cascade propagate through the wiring into MANC nerve-cord data; what comes out is a walking magnitude and a turn bias that modulate a hand-written tripod gait. It runs entirely in the browser on WebGPU with no install, and ships a separate science view. The README labels the motor mappings as explicit approximations, and the project predates the September 2026 wave by several months.
erojasoficial-byte/fly-brain README demo GIF (MIT)Enrique Rojas Aliaga, Universidad de San Martín de Porres
A solo project from Enrique Rojas Aliaga at Universidad de San Martín de Porres (Lima) that wires a spiking network of 138,639 FlyWire v783 neurons and 15.1 million synapses into a NeuroMechFly v2 body in MuJoCo, complete with compound eyes, legs and wings. The author reports vision-driven motion detection, olfactory chemotaxis, gustatory responses and emergent walking, flight and escape, and frames the work around how connectome plus embodied experience yields individual behavioural differences; a 2026 preprint is archived on Zenodo.
caparison1234
A Python project that runs 1,373 neurons and 22,400 synapses from the Winding et al. 2023 larval Drosophila connectome as LIF units and lets them drive a real-time MuJoCo larva body. Note the front end: a small Qwen2.5 0.5B language model converts typed text (English, Korean, Japanese or Chinese) into sensory drive, so 'danger' activates nociceptors and produces retreat or curling, and 'food smell' produces head scanning; the connectome itself is not perceiving anything. All 17 commits date from 2026-03-21, well before the September wave; no license is stated.
yc-h (FlyCircuit-based model)
An early single-cell-resolution spiking simulator of the fly brain written in C/C++, built not on an EM connectome but on neuron data from the FlyCircuit database (flycircuit.tw), with companion programs for predicting connections and inferring neuron polarity (SPIN). The repository accompanied a manuscript under review in November 2018 and includes experiments on seizure-like hyperactivity; it has not been touched since.
Philip K. Shiu et al.
The reference code for Shiu et al., "A Drosophila computational brain model reveals sensorimotor processing" (Nature, October 2024), a leaky integrate-and-fire model of the whole FlyWire brain implemented in Brian 2. Users activate neurons by FlyWire ID with Poisson input or silence them to mimic optogenetics and read out spike times and rates; both the v630 and v783 connectome releases are supported and Jupyter tutorials are included. Later projects such as Eon Systems' fly-brain build directly on it.
snedea (GitHub user)
A browser-based simulation by GitHub user snedea that runs a leaky integrate-and-fire network of all 139,255 FlyWire FAFB v783 neurons and 2.7 million connections inside a Web Worker, letting visitors poke the fly with food, touch, wind, light and temperature and watch unscripted behaviour emerge from the wiring. It began in March 2026 as a scale-up of heyseth's 302-neuron C. elegans worm-sim and is hosted at flybrain.app.
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